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  • 351.
    Johnsson, Anna
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Institutet.
    Xue-Franzen, Yongtao
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Intitutet.
    Lundin, Maria
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Institutet.
    Wright, Anthony P. H.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Institutet.
    Stress-specific role of fission yeast Gcn5 histone acetyltransferase in programming a subset of stress response genes2006Inngår i: Eukaryotic Cell, ISSN 1535-9778, E-ISSN 1535-9786, Vol. 5, nr 8, s. 1337-1346Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Gcn5 is a coactivator protein that contributes to gene activation by acetylating specific lysine residues within the N termini of histone proteins. Gcn5 has been intensively studied in the budding yeast, Saccharomyces cerevisiae, but the features of genes that determine whether they require Gcn5 during activation have not been conclusively clarified. To allow comparison with S. cerevisiae, we have studied the genome-wide role of Gcn5 in the distantly related fission yeast, Schizosaccharomyces pombe. We show that Gcn5 is specifically required for adaptation to KCl- and CaCl2-mediated stress in S. pombe. We have characterized the genome-wide gene expression responses to KCl stress and show that Gcn5 is involved in the regulation of a subset of stress response genes. Gcn5 is most clearly associated with KCl-induced genes, but there is no correlation between Gcn5 dependence and the extent of their induction. Instead, Gen5-dependent KCl-induced genes are specifically enriched in four different DNA motifs. The Gcn5-dependent KCl-induced genes are also associated with biological process gene ontology terms such as carbohydrate metabolism, glycolysis, and nicotinamide metabolism that together constitute a subset of the ontology parameters associated with KCl-induced genes.

  • 352.
    Jonsson, Magnus
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Bertilsson, Maria
    Ehrlén, Johan
    Lönn, Mikael
    Södertörns högskola, Institutionen för livsvetenskaper.
    Genetic divergence of climatically marginal populations of Vicia pisiformis on the Scandinavian Peninsula2008Inngår i: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 145, nr 1, s. 1-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Vicia pisiformis L. is a perennial leguminous plant with a main distribution in broadleaved forest-steppes of eastern Europe. The species is classified as endangered (EN) according to the IUCN red-lists in both Norway and Sweden, due to severe fragmentation, small population sizes and continuing population decline. The populations on the Scandinavian Peninsula constitute the northern limit of the species distribution and are mostly restricted to warm stony slopes with predominantly southern aspects. In this study we used the AFLP method, which is a high-resolution genetic fingerprint method. Samples were collected from 22 Scandinavian populations. The overall genetic structure was analysed in an AMOVA, in a Mantel test and through constrained correspondence analysis (CCA). The ordination scores representing non-geographic genetic divergence were extracted from the CCA and analysed in a linear model using habitat variables and population size as explanatory variables. We found (i) a strong geographic structure, (ii) significant genetic divergence between populations, (iii) that this genetic divergence remained significant even after removing the effect of geography in a partial CCA and (iv) that the remaining non-geographic part of genetic divergence (distance from the ordination centre) was associated with aspect, populations with a northern aspect were more genetically divergent. Aspect explains more variation than population size and is the only variable retained in the minimal adequate model. We suggest that local adaptation has caused this divergence from an expected geographical pattern of genetic variation. This explanation is further supported by the association between aspect and specific AFLP fragments. Many plant populations are relics of a different climate (Aguirre-Planter et al. 2000; Despres et al. 2002; Pico and Riba 2002). In response to long-term climate change, populations can either migrate towards a more favourable climate or adapt to the new conditions (delaVega 1996; Jump et al. 2006). Species with limited dispersal ability are at risk of reaching isolated dead-ends of decreasingly suitable habitat, without any suitable habitat within dispersal distance (Colas et al. 1997). Isolated populations have to use their inherent evolutionary potential and adapt to changes in environmental conditions, or they will go extinct. As population fragments go extinct, those that remain will become increasingly isolated from each other both spatially and also genetically as the level of gene flow declines with increasing distance. Such correlation between genetic dissimilarities and geographic distances, known as isolation by distance (Slatkin 1993; Wright 1943), when found, suggests a history of geographically limited gene flow (Kimura and Weiss 1964). On top of an isolation by distance pattern there might be other genetic structures to be found. Occasional long-distance dispersal events for example may disturb geographic patterns with puzzling allele distributions as a result (Nichols and Hewitt 1994). Genetic drift is a process that will affect any pattern of genetic variation in a random fashion. Local adaptation through natural selection is a process that, if sufficiently strong in comparison with gene flow and genetic drift, will create patterns where genetic differentiation is associated with certain environmental conditions (Wright 1951). Several studies have shown the importance of local adaptation of populations (reviewed by Kawecki and Ebert 2004) (see also Bonin et al. 2006; Knight and Miller 2004; Kolseth and Lönn 2005; Lönn et al. 1998). Local adaptation can be strong also at small spatial scales (Snaydon and Davies 1976; Lönn 1993) even though it is sometimes very limited in terms of the number of genes involved (Kärkkainen et al. 2004) Environmental variability provides a base for biological variation by imposing differentiated selection pressures resulting in local adaptation. Topography provides large environmental variation within a relatively small area and thereby provides a basis for small-scale local adaptations. Depending on the local topographic possibilities populations can either migrate up and down slopes or along the same altitude to a different aspect to find a suitable microclimate. The dispersal distance will be much shorter per degree of temperature change during altitudinal migration (Hewitt 1996), than during simple latitudinal migration across a flat landscape. Slope and aspect are two important topographic parameters that determine the influx level of solar radiation, especially towards the poles where the total global radiation decreases (Larcher 2003). Vicia pisiformis is an endangered poorly-dispersed long-lived forest herb with its main distribution across the semi-open broadleaved forest steppes of eastern Europe. The Scandinavian populations are believed to be climate relict populations from warmer times. Earlier genetic studies of V. pisiformis using allozymes, RAPD:s and morhology, have found low to very low levels of genetic variation (Gustafsson and Gustafsson 1994; Black-Samuelsson et al. 1997; Black-Samuelsson and Lascoux 1999). Therefore we used AFLP (amplified fragment length polymorphism) markers, which detect even very small genetic differences between individuals. AFLP mainly analyse neutral variation, as the major fraction of most genomes is assumed to be neutral. However, since the AFLP-fragments are distributed randomly throughout the whole genome some fragments may be situated so close to regions under selection that they become more or less linked to them. This linkage disequilibrium between molecular markers and regions under selection, often referred to as quantitative trait loci (QTL), forms the basis for both QTL-mapping and marker assisted selection (MAS), reviewed by Dekkers and Hospital (2002). Gardner and Latta (2006) for example, found QTL under selection in both natural environments and in the greenhouse. Markers have been found to be connected to biomass production (Cavagnaro et al. 2006) and environmental variation (Bonin et al. 2006; Jump et al. 2006; Porcher et al. 2006). In this study we examine 22 Swedish and Norwegian populations of Vicia pisiformis and ask (i) if there is genetic differentiation between these populations, (ii) if there is can it be explained in its entirety by geographic location or (iii) can it partly be explained by habitat characteristics, suggesting local adaptation, or population size, suggesting genetic drift. We show that populations are differentiated geographically and that genetic variation in addition to the geographical pattern is associated with habitat.

  • 353. Juntti-Berggren, L
    et al.
    Webb, D L
    Arkhammar, P O G
    Schultz, V
    Schweda, Elke K H
    Södertörns högskola, Avdelning Naturvetenskap.
    Tornheim, K
    Berggren, P O
    Dihydroxyacetone-induced oscillations in cytoplasmic free Ca2+ and the ATP/ADP ratio in pancreatic beta-cells at substimulatory glucose2003Inngår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 278, nr 42, s. 40710-40716Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Glucose stimulation of pancreatic beta-cells causes oscillatory influx of Ca2+, leading to pulsatile insulin secretion. We have proposed that this is due to oscillations of glycolysis and the ATP/ADP ratio, which modulate the activity of ATP-sensitive K+ channels. We show here that dihydroxyacetone, a secretagogue that feeds into glycolysis below the putative oscillator phosphofructokinase, could cause a single initial peak in cytoplasmic free Ca2+ ([Ca2+](i)) but did not by itself cause repeated oscillations in [Ca2+](i) in mouse pancreatic beta-cells. However, in the presence of a substimulatory concentration of glucose (4 mM), dihydroxyacetone induced [Ca2+](i) oscillations. Furthermore, these oscillations correlated with oscillations in the ATP/ADP ratio, as seen previously with glucose stimulation. Insulin secretion in response to dihydroxyacetone was transient in the absence of glucose but was considerably enhanced and somewhat prolonged in the presence of a substimulatory concentration of glucose, in accordance with the enhanced [Ca2+](i) response. These results are consistent with the hypothesized role of phosphofructokinase as the generator of the oscillations. Dihydroxyacetone may affect phosphofructokinase by raising the free concentration of fructose 1,6-bisphosphate to a critical level at which it activates the enzyme autocatalytically, thereby inducing the pulses of phosphofructokinase activity that cause the metabolic oscillations.

  • 354.
    Kagoshima, Hiroshi
    et al.
    Universität Basel, Basel, Switzerland /National Institute of Genetics, Shizuoka, Japan / Research Organization of Information and Systems (ROIS), Tokyo, Japan.
    Cassata, Giuseppe
    Universität Basel, Basel, Switzerland.
    Tong, Yong Guang
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Biologi. Karolinska Institute.
    Pujol, Nathalie
    Aix-Marseille Université, Marseille, France.
    Niklaus, Gisela
    Universität Basel, Basel, Switzerland.
    Bürglin, Thomas R.
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Biologi. Karolinska Institute / Universität Basel, Basel, Switzerland.
    The LIM homeobox gene ceh-14 is required for phasmid function and neurite outgrowth2013Inngår i: Developmental Biology, ISSN 0012-1606, E-ISSN 1095-564X, Vol. 380, nr 2, s. 314-323Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Transcription factors play key roles in cell fate specification and cell differentiation. Previously, we showed that the LIM homeodomain factor CEH-14 is expressed in the AFD neurons where it is required for thermotaxis behavior in Caenorhabditis elegans. Here, we show that ceh-14 is expressed in the phasmid sensory neurons, PHA and PHB, a number of neurons in the tail, i.e., PHC, DVC, PVC, PVN, PVQ PVT, PVW and PVR, as well as the touch neurons. Analysis of the promoter region shows that important regulatory elements for the expression in most neurons reside from -4 kb to -1.65 kb upstream of the start codon. Further, within the first introns are elements for expression in the hypodermis. Phylogenetic footprinting revealed numerous conserved motifs in these regions. In addition to the existing deletion mutation ceh-14(ch3), we isolated a new allele, ceh-14(ch2), in which only one LIM domain is disrupted. The latter mutant allele is partially defective for thermosensation. Analysis of both mutant alleles showed that they are defective in phasmid dye-filling. However, the cell body, dendritic outgrowth and ciliated endings of PHA and PHB appear normal, indicating that ceh-14 is not required for growth. The loss of a LIM domain in the ceh-14(ch2) allele causes a partial loss-of-function phenotype. Examination of the neurites of ALA and tail neurons using a ceh-14::GFP reporter shows abnormal axonal outgrowth and pathfinding.

  • 355. Kaiser, L
    et al.
    Velickovic, T C
    Badia-Martinez, D
    Adedoyin, J
    Thunberg, S
    Hallen, D
    Berndt, Kurt D
    Karolinska Institutet.
    Gronlund, H
    Gafvelin, G
    van Hage, M
    Achour, A
    Structural characterization of the tetrameric form of the major cat allergen Fel d 12007Inngår i: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 370, nr 4, s. 714-727Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Felis domesticus allergen 1(Fel d 1) is a 35 kDa tetrameric glycoprotein formed by two heterodimers which elicits IgE responses in 95% of patients with allergy to cat. We have previously established in vitro conditions for the appropriate folding of recombinant Fel d 1 using a direct linkage of chain 1 to chain 2 (construct Fel d 1 (1+2)) and chain 2 to chain 1 (construct Fel d 1 (2+1)). Although the crystal structure of Fel d 1 (2+1) revealed a striking structural similarity to that of uteroglobin, a steroid-inducible cytokine-like molecule with anti-inflammatory and immunomodulatory properties, no functional tetrameric form of Fel d 1 could be identified. Here we present the crystal structure of the Fel d 1 (1+2) tetramer at 1.6 A resolution. Interestingly, the crystal structure of tetrameric Fel d 1 reveals two different calcium-binding sites. Symmetrically positioned on each side of the Fel d 1 tetramer, the external Ca(2+)-binding sites correspond to a putative Ca(2+)-binding site previously suggested for uteroglobin. The second Ca(2+)-binding site lies within the dimerization interface, stabilizing the formation of the Fel d 1 tetramer, and inducing important local conformational changes that directly govern the shape of two water-filled cavities. The crystal structure suggests a potential portal for an unknown ligand. Alternatively, the two cavities could be used by the allergen as a conditional inner space allowing for the spatial rearrangement of centrally localized side-chains, such as Asp130, without altering the overall fold of the molecule. The striking structural similarity of the major cat allergen to uteroglobin, coupled to the identification in the present study of a common Ca(2+)-binding site, let us speculate that Fel d 1 could provoke an allergic response through the modulation of phospholipase A2, by sequestering Ca ions in a similar manner as previously suggested for uteroglobin.

  • 356.
    Kalokora, Olivia J
    et al.
    Dar es Salaam University College of Education (DUCE), Tanzania.
    Gullström, Martin
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Buriyo, Amelia S
    University of Dar es Salaam, Tanzania.
    Mtolera, Matern S P
    University of Dar es Salaam, Tanzania.
    Björk, Mats
    Stockholm University, Sweden.
    Seagrass meadows mixed with calcareous algae have higher plant productivity and sedimentary blue carbon storage2022Inngår i: Ecology and Evolution, E-ISSN 2045-7758, Vol. 12, nr 2, artikkel-id e8579Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Seagrass meadows capture and store large amounts of carbon in the sediment beneath, thereby serving as efficient sinks of atmospheric CO2. Carbon sequestration levels may however differ greatly among meadows depending on, among other factors, the plant community composition. Tropical seagrass meadows are often intermixed with macroalgae, many of which are calcareous, which may compete with seagrass for nutrients, light, and space. While the photosynthetic CO2 uptake by both seagrasses and calcareous algae may increase the overall calcification in the system (by increasing the calcium carbonate saturation state, Ω), the calcification process of calcareous algae may lead to a release of CO2, thereby affecting both productivity and calcification, and eventually also the meadows' carbon storage. This study estimated how plant productivity, CaCO3 production, and sediment carbon levels were affected by plant community composition (seagrass and calcareous algae) in a tropical seagrass-dominated embayment (Zanzibar, Tanzania). Overall, the patterns of variability in productivity differed between the plant types, with net areal biomass productivity being highest in meadows containing both seagrass and calcareous algae. Low and moderate densities of calcareous algae enhanced seagrass biomass growth, while the presence of seagrass reduced the productivity of calcareous algae but increased their CaCO3 content. Sedimentary carbon levels were highest when seagrasses were mixed with low or moderate cover of calcareous algae. The findings show that plant community composition can be an important driver for ecosystem productivity and blue carbon sequestration.

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  • 357. Karlsson, C.
    et al.
    Korayem, A. M.
    Scherfer, C.
    Loseva, O.
    Dushay, Mitchell S.
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Theopold, U.
    Proteomic analysis of the Drosophila larval hemolymph clot2004Inngår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 279, nr 50, s. 52033-52041Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Components of the insect clot, an extremely rapid forming and critical part of insect immunity, are just beginning to be identified (1). Here we present a proteomic comparison of larval hemolymph before and after clotting to learn more about this process. This approach was supplemented by the identification of substrates for the enzyme transglutaminase, which plays a role in both vertebrate blood clotting (as factor XIIIa) and hemolymph coagulation in arthropods. Hemolymph proteins present in lower amounts after clotting include CG8502 (a protein with a mucin-type domain and a domain with similarity to cuticular components), CG11313 (a protein with similarity to prophenoloxidase-activating proteases), and two phenoloxidases, lipophorin, a secreted gelsolin, and CG15825, which had previously been isolated from clots (2). Proteins whose levels increase after clotting include a ferritin-subunit and two members of the immunoglobulin family with a high similarity to the small immunoglobulin-like molecules involved in mammalian innate immunity. Our results correlate with findings from another study of coagulation (2) that involved a different experimental approach. Proteomics allows the isolation of novel candidate clotting factors, leading to a more complete picture of clotting. In addition, our two-dimensional protein map of cell-free Drosophila hemolymph includes many additional proteins that were not found in studies performed on whole hemolymph.

  • 358. Karlsson, Mikael
    Biosafety principles for GMOs in the context of sustainable development2003Inngår i: International Journal of Sustainable Development and World Ecology, ISSN 1350-4509, E-ISSN 1745-2627, Vol. 10, nr 1, s. 15-26Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    If genetically modified organisms are to contribute to welfare they must be considered in the context of sustainable development. Biosafety implies considering the environmental, economic and social dimensions of sustainable development. These dimensions can be interpreted through the principles of precaution, polluter pays and public participation. In this article, these key biosafety principles are operationalised and ways of implementing them in society are discussed. A comparison is made between the principles and the present EU law for deliberate release of GMOs. It is concluded that several improvements in EU policy are necessary to ensure sustainable development really is promoted.

  • 359. Karlsson, Mikael
    Ethics of sustainable development - a study of Swedish regulations for genetically modified organisms2003Inngår i: Journal of Agricultural and Environmental Ethics, ISSN 1187-7863, E-ISSN 1573-322X, Vol. 16, nr 1, s. 51-62Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In spite of stricter provisions in the new EU directive on deliberate release of genetically modified organisms (GMOs), critics still advocate a moratorium on permits for cultivation of GMOs. However, in an attempt to meet concerns raised by the public, the directive explicitly gives Member States the possibility to take into consideration ethical aspects of GMOs in the decision-making. This article investigates the potential effects of such formulation by means of an empirical analysis of experiences gained the last years from similar Swedish regulations for GMOs, aiming at promoting sustainable development. The faulty implementation shown in the Swedish case indicates that legal stipulations for ethics as such have limited importance. It is suggested that public participation is an important factor for successful implementation of the ethics of sustainable development.

  • 360.
    Karlsson, Mikael
    Karlstads universitet.
    Managing complex environmental risks for sustainable development: policies for hazardous chemicals and genetically modified organisms2005Doktoravhandling, med artikler (Annet vitenskapelig)
  • 361. Karlsson, Mikael
    Regulatory frameworks for sustainable control of genetically modified organisms2000Inngår i: Third International Conference of the European Society for Ecological Economics on transitions towards a sustainable Europe: ecology, economy, policy : Vienna, May 3 to 6, 2000, Vienna, 2000Konferansepaper (Annet vitenskapelig)
  • 362. Karlsson, Mikael
    Science and norms in policies for sustainable development: Assessing and managing risks of chemical substances and genetically modified organisms in the European Union2006Inngår i: Regulatory toxicology and pharmacology, ISSN 0273-2300, E-ISSN 1096-0295, Vol. 44, nr 1, s. 49-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Use of chemical substances and genetically modified organisms cause complex problems characterised by scientific uncertainty and controversies. Aiming at sustainable development, policies for assessment, and management of risks in the two areas are under development in the European Union. The article points out that both science and norms play a central role in risk assessment as well as risk management and Suggests that the precautionary principle, the principle of public participation, and the polluter pays principle, all adopted in the European Union, offer a way to operationalise the concept of sustainable development. It is shown, however, that a number of steps ought to be taken to better implement the principles through different policy measures. In doing so, and by recognising the role of both science and norms, the decision-making on risks related to the use of chemicals or genetically modified organisms can be improved to better promote Sustainable development.

  • 363. Karlsson, Mikael
    Theories on Risk, and the Management of Genetically Modified Organisms: a Stakeholders AnalysisManuskript (preprint) (Annet vitenskapelig)
  • 364. Kaumaya, P T P
    et al.
    Berndt, Kurt D
    University of Chicago, USA.
    Heidorn, D B
    Trewhella, J
    Kezdy, F J
    Goldberg, E
    Synthesis and Biophysical Characterization of Engineered Topographic Immunogenic Determinants with Alpha-Alpha-Topology1990Inngår i: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 29, nr 1, s. 13-23Artikkel i tidsskrift (Fagfellevurdert)
  • 365.
    Kellner, Martin
    et al.
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Porseryd, Tove
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Hallgren, S
    Uppsala University.
    Porsch-Hällström, Inger
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Biologi.
    Hansen, S H
    University of Copenhagen, Denmark.
    Olsén, K Håkan
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Biologi.
    Waterborne citalopram has anxiolytic effects and increases locomotor activity in the three-spine stickleback (Gasterosteus aculeatus)2016Inngår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 173, s. 19-28Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Citalopram is an antidepressant drug, which acts by inhibiting the re-uptake of serotonin from the synaptic cleft into the pre-synaptic nerve ending. It is one of the most common drugs used in treatment of depression, it is highly lipophilic and frequently found in sewage treatment plant effluents and surface waters around the world. Citalopram and other selective serotonin re-uptake inhibitors have, at concentrations that occur in nature, been shown to have behavioural as well as physiological effects on fish and other animals. This study is the result of several different experiments, intended to analyse different aspects of behavioural effects of chronic citalopram exposure in fish. Our model species the three-spine stickleback is common in the entire northern hemisphere and is considered to be a good environmental sentinel species. Female three-spine sticklebacks were exposed to 0, 1.5 and 15μg/l nominal concentrations of citalopram for 21 days and subjected to the novel tank (NT) diving test. In the NT test, the fish exposed to 1.5μg/l, but not the 15μg/l fish made a significantly higher number of transitions to the upper half and stayed there for significantly longer time than the fish exposed to 0μg/l. The 15μg/l group, however, displayed a significantly lower number of freeze bouts and a shorter total freezing time. The test for locomotor activity included in the NT test showed that fish treated with 1.5 and 15μg/l displayed a significantly higher swimming activity than control fish both 5-7 and 15-17min after the start of the experiment. In the next experiment we compared fish exposed to 1.5μg/l and 0.15μg/l to pure water controls with regard to shoaling intensity and found no effect of treatment. In the final experiment the propensity of fish treated with 1.5μg/l to approach an unknown object and aggressive behaviour was investigated using the Novel Object test and a mirror test, respectively. The exposed fish ventured close to the unknown object significantly more often and stayed there for significantly longer time than unexposed fish. The aggression test yielded no statistically significant effects. It is concluded that citalopram changes the behaviour of the three-spine stickleback in a way that is likely to have ecological consequences and that it must not be considered an environmentally safe pharmaceutical.

  • 366. Khorosjutina, Olga
    et al.
    Wanrooij, Paulina H.
    Walfridsson, Julian
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Szilagyi, Zsolt
    Zhu, Xuefeng
    Baraznenok, Vera
    Ekwall, Karl
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Gustafsson, Claes M.
    A Chromatin-remodeling Protein Is a Component of Fission Yeast Mediator2010Inngår i: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 285, nr 39, s. 29729-29737Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The multiprotein Mediator complex is an important regulator of RNA polymerase II-dependent genes in eukaryotic cells. In contrast to the situation in many other eukaryotes, the conserved Med15 protein is not a stable component of Mediator isolated from fission yeast. We here demonstrate that Med15 exists in a protein complex together with Hrp1, a CHD1 ATP-dependent chromatin-remodeling protein. The Med15-Hrp1 subcomplex is not a component of the core Mediator complex but can interact with the L-Mediator conformation. Deletion of med15(+) and hrp1(+) causes very similar effects on global steady-state levels of mRNA, and genome-wide analyses demonstrate that Med15 associates with a distinct subset of Hrp1-bound gene promoters. Our findings therefore indicate that Mediator may directly influence histone density at regulated promoters.

  • 367.
    Kieselbach, T
    et al.
    Karolinska Institutet.
    Bystedt, Maria
    Södertörns högskola, Avdelning Naturvetenskap. Karolinska Institutet.
    Hynds, P
    University of Warwick, UK.
    Robinson, C
    University of Warwick, UK.
    Schröder, Wolfgang P
    Södertörns högskola, Avdelning Naturvetenskap.
    A peroxidase homologue and novel plastocyanin located by proteomics to the Arabidopsis chloroplast thylakoid lumen2000Inngår i: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 480, nr 2-3, s. 271-276Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A study by two-dimensional electrophoresis showed that the soluble, lumenal fraction of Arabidopsis thaliana thylakoids can be resolved into 300 protein spots. After subtraction of low-intensity spots and accounting for low-level stromal contamination, the number of more abundant, lumenal proteins was estimated to be between 30 and 60. Two of these proteins have been identified: a novel plastocyanin that also was the predominant component of the total plastocyanin pool, and a putative ascorbate peroxidase. Import studies shamed that these proteins are routed to the thylakoid lumen by the Sec- and delta pH-dependent translocation pathways, respectively, In addition, novel isoforms of PsbO and PsbQ were identified.

  • 368.
    Kiessling, Anders
    et al.
    SLU.
    Futter, Martyn
    SLU.
    Elofsson, Katarina
    Södertörns högskola, Institutionen för samhällsvetenskaper, Nationalekonomi. SLU.
    Vidakovic, Aleksandar
    SLU.
    Musselodling i Östersjön som miljöåtgärd: nya positiva data från tre pågående EU-projekt2019Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Nya resultat visar att musselodlingar i Östersjön har en betydande potential att bidra till att minska övergödningen samtidigt som förutsättningar skapas för en cirkulär ekonomi/produktion. För att ta musselodling till nästa nivå krävs dels ytterligare förfining av den nya tekniken, men framförallt fler och i förlängningen också större odlingar samtidigt som vi måste vidareutveckla alla de initiativ som nu pågår hur näringen kan återanvändas i livsmedelssystemet på ett effektivt och ekonomiskt lönsamt sätt.

    Fulltekst (pdf)
    fulltext
  • 369.
    Kihlmark, Madeleine
    Södertörns högskola, Avdelning Naturvetenskap. Stockholms universitet.
    Targeting of a nascent integral membrane protein to the nuclear pores and its degradation during apoptosis2002Doktoravhandling, med artikler (Annet vitenskapelig)
  • 370.
    Kihlmark, Madeleine
    et al.
    Södertörns högskola, Avdelning Naturvetenskap.
    Imreh, Gabriela
    Södertörns högskola, Avdelning Naturvetenskap.
    Hallberg, Einar
    Södertörns högskola, Avdelning Naturvetenskap.
    Sequential degradation of proteins from the nuclear envelope during apoptosis2001Inngår i: Journal of Cell Science, ISSN 0021-9533, E-ISSN 1477-9137, Vol. 114, nr 20, s. 3643-3653Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have produced new antibodies specific for the integral pore membrane protein POM121. Using these antibodies we show that during apoptosis POM121 becomes proteolytically degraded in a caspase-dependent manner. The POM121 antibodies and antibodies specific for other proteins of the nuclear envelope were used in a comparative study of nuclear apoptosis in staurosporine-treated buffalo rat liver cells. Nuclei from these cells were classified in three different stages of apoptotic progression: stage I, moderately condensed chromatin surrounded by a smooth nuclear periphery; stage II, compact patches of condensed chromatin collapsing against a smooth nuclear periphery; stage III, round compact chromatin bodies surrounded by grape-shaped nuclear periphery. We have performed double labeling immunofluorescence microscopy of individual apoptotic cells and quantitative immunoblotting analysis of total proteins from apoptotic cell cultures. The results showed that degradation of nuclear envelope marker proteins occurred in a specific order. POM121 degradation occurred surprisingly early and was initiated before nucleosomal DNA degradation could be detected using TUNEL assay and completed before clustering of the nuclear pores. POM121 was eliminated significantly more rapid compared with NUP153 (a peripheral protein located in the nucleoplasmic basket of the nuclear pore complex) and lamin B (a component of the nuclear lamina). Disappearance of NUP153 and lamin B was coincident with onset of DNA fragmentation and clustering of nuclear pores. By contrast, the peripheral NPC protein p62 was degraded much later. The results suggest that degradation of POM121 may be an important early step in propagation of nuclear apoptosis.

  • 371.
    Kihlmark, Madeleine
    et al.
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap. Stockholm University.
    Rustum, Cecilia
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap. Stockholm University.
    Eriksson, Charlotta
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap. Karolinska Institutet.
    Beckman, M
    Stockholm University.
    Iverfeldt, K
    Stockholm University.
    Hallberg, Einar
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Correlation between nucleocytoplasmic transport and caspase-3-dependent dismantling of nuclear pores during apoptosis2004Inngår i: Experimental Cell Research, ISSN 0014-4827, E-ISSN 1090-2422, Vol. 293, nr 2, s. 346-356Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During apoptosis (also called programmed cell death), the chromatin condenses and the DNA is cleaved into oligonucleosomal fragments. Caspases are believed to play a major role in nuclear apoptosis. However, the relation between dismantling of nuclear pores, disruption of the nucleocytoplasmic barrier, and nuclear entry of caspases is unclear. We have analyzed nuclear import of the green fluorescent protein fused to a nuclear localization signal (GFP-NLS) in tissue culture cells undergoing apoptosis. Decreased nuclear accumulation of GFP-NLS could be detected at the onset of nuclear apoptosis manifested as dramatic condensation and redistribution of chromatin toward the nuclear periphery. At this step, dismantling of nuclear pores was already evident as indicated by proteolysis of the nuclear pore membrane protein POM121. Thus, disruption of nuclear compartmentalization correlated with early signs of nuclear pore damage. Both these events clearly preceded massive DNA fragmentation, detected by TUNEL assay. Furthermore, we show that in apoptotic cells, POM121 is specifically cleaved at aspartate-531 in its large C-terminal portion by a caspase-3-dependent mechanism. Cleavage of the C-terminal portion of POM121, which is adjoining the nuclear pore complex, is likely to disrupt interactions with other nuclear pore proteins affecting the stability of the pore complex. A temporal correlation of apoptotic events supports a model where caspase-dependent disassembly of nuclear pores and disruption of the nucleocytoplasmic barrier paves the way for nuclear entry of caspases and subsequent activation of CAD-mediated DNA fragmentation.

  • 372.
    Kihlmark, Madeleine
    et al.
    Södertörns högskola, Avdelning Naturvetenskap. Stockholms unviersitet.
    Rustum, Cecilia
    Södertörns högskola, Avdelning Naturvetenskap. Stockholms universitet.
    Eriksson, Charlotta
    Södertörns högskola, Avdelning Naturvetenskap. Karolinska institutet.
    Beckman, M
    Stockholms universitet.
    Iverfeldt, Kerstin
    Stockholms universitet.
    Hallberg, Einar
    Södertörns högskola, Avdelning Naturvetenskap.
    Caspase-3 dependent cleavage of POM121 in relation to nuclear apoptosisManuskript (preprint) (Annet vitenskapelig)
  • 373.
    Kitambi, Satish S.
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet / Harvard Medical School/MEEI, Boston, Massachusetts, USA.
    Malicki, Jarema J.
    Harvard Medical School/MEEI, Boston, Massachusetts, USA.
    Spatiotemporal Features of Neurogenesis in the Retina of Medaka, Oryzias latipes2008Inngår i: Developmental Dynamics, ISSN 1058-8388, E-ISSN 1097-0177, Vol. 237, nr 12, s. 3870-3881Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The vertebrate retina is very well conserved in evolution. Its structure and functional features are very similar in phyla as different as primates and teleost fish. Here, we describe the spatiotemporal characteristics of neurogenesis in the retina of a teleost, medaka, and compare them with other species, primarily the zebrafish. Several intriguing differences are observed between medaka and zebrafish. For example, photoreceptor differentiation in the medaka retina starts independently in two different areas, and at more advanced stages of differentiation, medaka and zebrafish retinae display obviously different patterns of the photoreceptor cell mosaic. Medaka and zebrafish evolutionary lineages are thought to have separated from each other 110 million years ago, and so the differences between these species are not unexpected, and may be exploited to gain insight into the architecture of developmental pathways. Importantly, this work highlights the benefits of using multiple teleost models in parallel to understand a developmental process.

  • 374.
    Kitambi, Satish S.
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet / Harvard Medical School/MEEI, Boston, USA.
    McCulloch, Kyle J.
    Harvard Medical School/MEEI, Boston, USA.
    Peterson, Randall T.
    Massachusetts General Hospital, USA.
    Malicki, Jarema J.
    Harvard Medical School/MEEI, Boston, USA.
    Small molecule screen for compounds that affect vascular development in the zebrafish retina2009Inngår i: Mechanisms of Development, ISSN 0925-4773, E-ISSN 1872-6356, Vol. 126, nr 5-6, s. 464-477Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Blood vessel formation in the vertebrate eye is a precisely regulated process. in the human retina, both an excess and a deficiency of blood vessels may lead to a loss of vision. To gain insight into the molecular basis of vessel formation in the vertebrate retina and to develop pharmacological means of manipulating this process in a living organism, we further characterized the embryonic zebrafish eye vasculature, and performed a small molecule screen for compounds that affect blood vessel morphogenesis. The screening of approximately 2000 compounds revealed four small molecules that at specific concentrations affect retinal vessel morphology but do not produce obvious changes in trunk vessels, or in the neuronal architecture of the retina. Of these, two induce a pronounced widening of vessel diameter without a substantial loss of vessel number, one compound produces a loss of retinal blood vessels accompanied by a mild increase of their diameter, and finally one other generates a severe loss of retinal vessels. This work demonstrates the utility of zebrafish as a screening tool for small molecules that affect eye vasculature and presents several compounds of potential therapeutic importance.

  • 375.
    Kitambi, Satish Srinivas
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Teleost retina: a model for study neurogenesis and angiogenesis2009Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Teleost models, zebrafish and medaka have become popular models to study various aspects of developmental biology and genetics. The rapid embryonic development, transparent embryos and the availability of many mutants for various developmental and molecular pathways contribute to the usefulness of these models. The availability of various biochemical, molecular and genetic techniques applicable on these models facilitate in dissecting developmental processes. Teleost retina shows very high similarity to that seen in mammalian retina. The arrangement of the six types of neurons and one type of glia is very similar. Zebrafish has been extensively used in gaining insight into the development and functioning of the retina. Medaka, on the other hand has not been so extensively capitalized as zebrafish. The current study characterizes expression of genes mainly from the nuclear receptor family and establishes the role of zebrafish liver x receptor in governing the size, patterning and neurogenesis of the retina in zebrafish. We also establish the time line of the retinal patterning of medaka retina. Zebrafish and medaka retina show both similarity and difference in the developmental events governing the patterning of the retina. In zebrafish, retinal neurogenesis follows a fan gradient pattern starting at the ventro-nasal region. In medaka, neurogenesis starts from the central retina. An additional, second domain of neurogenesis is seen with the patterning of photoreceptors in medaka. This observation highlights the possibility of utilizing these two species as comparative models in gaining rapid understanding of retinal development and function. This study also establishes the time line of vascular development in the zebrafish retina, an important event required for normal function. Similar to neurogenesis, vasculaturedevelops rapidly and this feature was utilized to develop a small molecule-screening assay. The screening resulted in identification of five compounds that produced phenotype ranging from decrease in the number of vessels to loss of vessels specifically in the retina. To gain insight into the mode of action, further analyses of three of the five identified compounds, using either morpholino knockdown or structural similarity search was done. This study highlights the advantage of using zebrafish model to perform medically relevant chemical screen.

  • 376.
    Kitambi, Satish Srinivas
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Archer, Amena
    Karolinska Institutet.
    Hallgren, Stefan
    Södertörns högskola, Institutionen för livsvetenskaper.
    Olsén, K Håkan
    Södertörns högskola, Institutionen för livsvetenskaper.
    Gustafsson, Åke
    Karolinska Institutet.
    Mode, Agneta
    Karolinska Institutet.
    The role of liver X receptor (lxr) in the developing eyeManuskript (preprint) (Annet vitenskapelig)
  • 377.
    Kitambi, Satish Srinivas
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Hauptmann, Giselbert
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    The zebrafish orphan nuclear receptor genes nr2e1 and nr2e3 are expressed in developing eye and forebrain2007Inngår i: Gene Expression Patterns, ISSN 1567-133X, E-ISSN 1872-7298, Vol. 7, nr 4, s. 521-528Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mammalian Nr2e1 (Tailless, Mtll or Tlx) and Nr2e3 (photoreceptor-specific nuclear receptor, Pnr) are highly related orphan nuclear receptors, that are expressed in eye and forebrain-derived structures. In this study, we analyzed the developmental expression patterns of zebrafish nr2e1 and nr2e3. RT-PCR analysis showed that nr2e1 and nr2e3 are both expressed during embryonic and post-embryonic development. To examine the spatial distribution of nr2e1 and nr2e3 during development whole-mount in situ hybridization was performed. At tailbud stage, initial nr2e1 expression was localized to the rostral brain rudiment anterior to pax2.1 and eng2 expression at the prospective midbrain-hindbrain boundary. During Subsequent stages, nr2e1 became widely expressed in fore- and midbrain primordia, eye and olfactory placodes. At 24 hpf, strong nr2e1 expression was detected in telencephalon, hypothalamus, dorsal thalamus, pretectum, midbrain tectum, and retina. At 2 dpf, the initially widespread nr2e1 expression became more restricted to distinct regions within the fore- and midbrain and to the retinal ciliary margin, the germinal zone which gives rise to retina and presumptive iris. Express on of nr2e3 was exclusively found in the developing retina and epiphysis. In both structures, nr2e3 expression was found in photoreceptor cells. The developmental expression profile of zebrafish nr2e1 and nr2e3 is consistent with evolutionary conserved functions in eye and rostral brain structures.

  • 378. Knapp, S
    et al.
    Karshikoff, A
    Berndt, Kurt D
    Karolinska Institutet.
    Christova, P
    Atanasov, B
    Ladenstein, R
    Thermal unfolding of the DNA-binding protein Sso7d from the hyperthermophile Sulfolobus solfataricus1996Inngår i: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 264, nr 5, s. 1132-1144Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal unfolding of the small hyperthermophilic DNA-binding protein Sso7d was studied by circular dichroism spectroscopy and differential scanning calorimetry. The unfolding transition can be described by a reversible two state process. Maximum stability was observed in the region between pH 4.5 and 7.0 where Sso7d unfolds with a melting temperature between 370.8 to 371.9 K and an unfolding enthalpy between 62.9 and 65.4 kcal/mol. The heat capacity differences between the native and the heat denatured states obtained by differential scanning calorimetry (620 cal/(mol K)) and circular dichroism spectroscopy (580 cal/(mol K)) resulted in comparable values. The thermodynamic reason for the high melting temperature of Sso7d is the shallow stability curve with a broad free energy maximum, corresponding to the relatively small heat capacity change which was obtained. The calculated stability curve shows that Sso7d has, despite of its high melting temperature, an only moderate intrinsic stability, which reaches its maximum (approximate to 7 kcal/mol) at 282 K. Sso7d is particularly poorly stabilized (approximate to 1 kcal/mol) at the maximum physiological growth temperature of Sulfolobus solfataricus. Sso7d has furthermore untypically low specific enthalpy (0.99 kcal/(mol residue)) and entropy (2.99 cal/(mol K)) values at convergence temperatures. No significant differences in thermal stability of the partially methylated Sso7d from Sulfolobus solfataricus and the cloned non-methylated form of the protein expressed in Escherichia coli were observed. (C) 1996 Academic Press Limited

  • 379. Knapp, S
    et al.
    Mattson, P T
    Christova, P
    Berndt, Kurt D
    Karolinska Institutet.
    Karshikoff, A
    Vihinen, M
    Smith, C I E
    Ladenstein, R
    Thermal unfolding of small proteins with SH3 domain folding pattern1998Inngår i: Proteins: Structure, Function, and Bioinformatics, ISSN 0887-3585, E-ISSN 1097-0134, Vol. 31, nr 3, s. 309-319Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The thermal unfolding of three SH3 domains of the Tec family of tyrosine kinases was studied by differential scanning calorimetry and CD spectroscopy, The unfolding transition of the three protein domains in the acidic pH region can be described as a reversible two-state process. For all three SH3 domains maximum stability was observed in the pH region 4.5 < pH < 7.0 where these domains unfold at temperatures of 353K (Btk), 342K (Itk), and 344K (Tec), At these temperatures an enthalpy change of 196 kJ/mol, 178 kJ/mol, and 169 kJ/mol was measured for Btk-, Itk-, and Tec-SH3 domains, respectively. The determined changes in heat capacity between the native and the denatured state are in an usual range expected for small proteins. Our analysis revealed that all SH3 domains studied are only weakly stabilized and have free energies of unfolding which do not exceed 12-16 kJ/mol but show quite high melting temperatures. Comparing unfolding free energies measured for eukaryotic SH3 domains with those of the topologically identical Sso7d protein from the hyperthermophile Sulfolobus solfataricus, the increased melting temperature of the thermostable protein is due to a broadening as well as a significant lifting of its stability curve. However, at their physiological temperatures, 310K for mesophilic SH3 domains and 350K for Sso7d, eukaryotic SH3 domains and Sso7d show very similar stabilities. (C) 1998 Wiley-Liss, Inc.

  • 380.
    Kniola, Barbara
    et al.
    Södertörns högskola, Avdelning Naturvetenskap. Karolinska Institutet.
    O'Toole, E
    McIntosh, J R
    Mellone, B
    Allshire, R
    Mengarelli, S
    Hultenby, K
    Ekwall, Karl
    Södertörns högskola, Avdelning Naturvetenskap. Karolinska Institutet.
    The domain structure of centromeres is conserved from fission yeast to humans2001Inngår i: Molecular Biology of the Cell, ISSN 1059-1524, E-ISSN 1939-4586, Vol. 12, nr 9, s. 2767-2775Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The centromeric DNA of fission yeast is arranged with a central core flanked by repeated sequences. The centromere-associated proteins, Mis6p and Cnp1p (SpCENP-A), associate exclusively with central core DNA, whereas the Swi6 protein binds the surrounding repeats. Here, electron microscopy and immunofluorescence light microscopy reveal that the central core and flanking regions occupy distinct positions within a heterochromatic domain. An "anchor" structure containing the Ndc80 protein resides between this heterochromatic domain and the spindle pole body. The organization of centromere-associated proteins in fission yeast is reminiscent of the multilayered structures of human kinetochores, indicating that such domain structure is conserved in eukaryotes.

  • 381. Knorpp, Carina
    et al.
    Hugosson, Marie
    Sjöling, Sara
    Eriksson, AnnaCarin
    Glaser, Elzbieta
    Tissue-specific differences of the mitochondrial protein import machinery: in vitro import, processing and degradation of the pre-F1β subunit of the ATP synthase in spinach leaf and root mitochondria1994Inngår i: Plant Molecular Biology, ISSN 0167-4412, E-ISSN 1573-5028, Vol. 26, nr 2, s. 571-579Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study we report the first comparison of the mitochondrial protein import and processing events in two different tissues from the same organism. Both spinach leaf and root mitochondria were able to import and process the in vitro transcribed and translated Neurospora crassa F1 subunit of ATP synthase to the mature size product. Temperature optimum for protein import, 20 °C, was considerably lower than that found in other systems. In spinach leaf mitochondria, the processing peptidase has been shown to constitute an integral part of the bc1 complex of the respiratory chain. In accordance with these results, the majority of the processing activity in root mitochondria was also localized in the membrane. However, although the same amount of the processing peptidase was present per mg of membrane protein in both leaf and root mitochondria, as determined immunologically, the specific processing activity was several-fold higher in roots. Furthermore, in contrast to the processing enzyme in leaf, a portion of the processing activity could be disassociated from the root membrane with relatively weak salt treatment. The processing event in both the leaf and root membranes was always accompanied by a degradation of the F1 precursor. The degradation activity was found to be several-fold higher in roots than in leaves and was also partially dissociated from the membrane after salt treatment. Both the processing and degradation activities were inhibited by orthophenanthroline, a known metalloprotease inhibitor. These results show tissue-specific differencies of the processing event catalyzed by the bc1 complex and indicate the presence of two populations of the processing peptidase in root mitochondria.

  • 382.
    Knutsson Jenvert, Rose-Marie
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Stockholm University.
    Holmberg Schiavone, Lovisa
    Södertörns högskola, Institutionen för livsvetenskaper.
    Characterization of the tRNA and ribosome-dependent pppGpp-synthesis by recombinant stringent factor from Escherichia coli2005Inngår i: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 272, nr 3, s. 685-695Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stringent factor is a ribosome-dependent ATP:GTP pyrophosphoryl transferase that synthesizes (p)ppGpp upon nutrient deprivation. It is activated by unacylated tRNA in the ribosomal amino-acyl site (A-site) but it is unclear how activation occurs. A His-tagged stringent factor was isolated by affinity-chromatography and precipitation. This procedure yielded a protein of high purity that displayed (a) a low endogenous pyrophosphoryl transferase activity that was inhibited by the antibiotic tetracycline; (b) a low ribosome-dependent activity that was inhibited by the A-site specific antibiotics thiostrepton, micrococcin, tetracycline and viomycin; (c) a tRNA- and ribosome-dependent activity amounting to 4500 pmol pppGpp per pmol stringent factor per minute. Footprinting analysis showed that stringent factor interacted with ribosomes that contained tRNAs bound in classical states. Maximal activity was seen when the ribosomal A-site was presaturated with unacylated tRNA. Less tRNA was required to reach maximal activity when stringent factor and unacylated tRNA were added simultaneously to ribosomes, suggesting that stringent factor formed a complex with tRNA in solution that had higher affinity for the ribosomal A-site. However, tRNA-saturation curves, performed at two different ribosome/stringent factor ratios and filter-binding assays, did not support this hypothesis.

  • 383.
    Koeck, Philip J. B.
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. KTH / Karoliska institutet.
    Purhonen, P.
    Alvang, R.
    Grundberg, B.
    Hebert, H.
    Single particle refinement in electron crystallography: A pilot study2007Inngår i: Journal of Structural Biology, ISSN 1047-8477, E-ISSN 1095-8657, Vol. 160, nr 3, s. 344-352Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Electron crystallography can be used to determine the structures of membrane proteins at near-atomic resolution in some cases. However, most electron crystallography projects remain at a resolution around 10 Å. This might be partly due to lack of flatness of many two-dimensional crystals. We have investigated this problem and suggest single particle processing of locally averaged unit cells to improve the quality and possibly the resolution of three-dimensional maps. Applying this method to the secondary transporter melibiose permease we have calculated a three-dimensional map that is clearer and easier to interpret than the map derived using purely electron-crystallographic methods.

  • 384.
    Kolseth, Anna-Karin
    Södertörns högskola, Institutionen för livsvetenskaper. Uppsala universitet.
    Evolutionary Processes and Spatial Genetic Variation in Euphrasia stricta on the Baltic Island of Gotland2008Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The identification of processes governing genetic structure at different spatial scales remains a major challenge in evolutionary biology and is of considerable applied interest in conservation biology. In Euphrasia stricta five varieties have been identified (brevipila, gotlandica, stricta, suecica and tenuis) based on differences in habitat, phenology and morphology. In this thesis, I examined genetic variation at AFLP and microsatellite marker loci in relation to variation in habitat and morphology within and among varieties of E. stricta on the island Gotland in the Baltic Sea. The results are discussed in relation to evolutionary processes acting within this species complex.

    In a study conducted at the regional scale, the two early-flowering varieties suecica and tenuis each formed a genetically distinct group, while the three late-flowering varieties brevipila, gotlandica and stricta formed a third group. The results suggest that suecica and tenuis have ancient origins since they are genetically different both from the brevipila/gotlandica/stricta group and from each other despite their similar habitat preferences. This pattern was obtained using both marker systems. Discrepancies between AFLP and microsatellites were found in patterns of isolation by distance and in estimates of expected heterozygosity, He.

    Focusing on the mixed genetic group brevipila/gotlandica/stricta and the causes behind their clustering together despite differences in morphology and habitat preferences, I performed a study at a smaller geographic scale. Studying a population of E. stricta I found that, although gene flow within the population was strong, it had not prevented the formation of genetic groups associated with micro-habitat properties.

    An important result for conservation of the rare variety suecica is its distinct genetic separation from variety tenuis. If the aim of conservation is to preserve the uniqueness of suecica, the two varieties should be treated as separated entities.

  • 385.
    Kolseth, Anna-Karin
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Uppsala universitet.
    Lönn, Mikael
    Södertörns högskola, Institutionen för livsvetenskaper.
    Habitat Associations of Fine-scale Genetic Structure in an Euphrasia stricta PopulationManuskript (preprint) (Annet vitenskapelig)
  • 386.
    Kolseth, Anna-Karin
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Uppsala universitet.
    Lönn, Mikael
    Södertörns högskola, Institutionen för livsvetenskaper.
    Regional Genetic Structure in the Tetraploid Hemiparasite Euphrasia stricta Inferred from MicrosatellitesManuskript (preprint) (Annet vitenskapelig)
  • 387.
    Korayem, A M
    et al.
    Stockholms universitet / Assiut University, Assiut, Egypt.
    Fabbri, M
    University of Adelaide, Glen Osmond, South Australia.
    Takahashi, K
    National Institute of Genetics, Shizuoka, Japan.
    Scherfer, C
    Stockholms universitet.
    Lindgren, Malin
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Schmidt, O
    University of Adelaide, Glen Osmond, South Australia.
    Ueda, R
    National Institute of Genetics, Shizuoka, Japan.
    Dushay, Mitchell S
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Theopold, U
    Stockholms universitet / University of Adelaide, Glen Osmond, South Australia.
    A Drosophila salivary gland mucin is also expressed in immune tissues: evidence for a function in coagulation and the entrapment of bacteria2004Inngår i: Insect Biochemistry and Molecular Biology, ISSN 0965-1748, E-ISSN 1879-0240, Vol. 34, nr 12, s. 1297-1304Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Our studies on the developmental regulation of glycosylation in Drosophila melanogaster led us to identify and characterize gp 150, an ecdysone-regulated mucin that is found in hemocytes, the gut (peritrophic membrane) and in the salivary glands. We are particularly interested in mucin immune functions and found that gp 150 is released from larval hemocytes, becomes part of the clot and participates in the entrapment of bacteria. By RT-PCR and RNAi experiments, we identified gp 150 as the previously described 171-7, an ecdysone-induced salivary glue protein. We discuss the evolutionary and biochemical implications of the dual use of salivary proteins for immune functions in insects. Further molecular characterization of such shared proteins may enable a better understanding of the properties of proteins involved in containment and elimination of microbes, as well as hemostasis and wound repair.

  • 388.
    Korayem, Ahmed M.
    et al.
    Stockholms universitet / Assiut University, Assiut, Egypt.
    Hauling, Thomas
    Stockholms universitet.
    Lesch, Christine
    Stockholms universitet.
    Fabbri, Marco
    University of Adelaide, Glen Osmond, Australia.
    Lindgren, Malin
    Södertörns högskola, Institutionen för livsvetenskaper. Stockholms universitet.
    Loseva, Olga
    Stockholms universitet.
    Schmidt, Otto
    University of Adelaide, Glen Osmond, Australia.
    Dushay, Mitchell S.
    Södertörns högskola, Institutionen för livsvetenskaper. Uppsala University.
    Theopold, Ulrich
    Stockholms universitet.
    Evidence for an immune function of lepidopteran silk proteins2007Inngår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 352, nr 2, s. 317-322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hemolymph coagulation stops bleeding and protects against infection. Clotting factors include both proteins that are conserved during evolution as well as more divergent proteins in different species. Here we show that several silk proteins also appear in the clot of the greater wax moth Galleria mellonella. RT-PCR analysis reveals that silk proteins are expressed in immune tissues and induced upon wounding in both Galleria and Ephestia kuehniella, a second pyralid moth. Our results support the idea that silk proteins were co-opted for immunity and coagulation during evolution.

  • 389.
    Koroxenidou, Lena
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Ohlson, Lena C. E.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Porsch Hällström, Inger
    Södertörns högskola, Institutionen för livsvetenskaper.
    Long-term 17 alpha-ethinyl estradiol treatment decreases cyclin E and cdk2 expression, reduces cdk2 kinase activity and inhibits S phase entry in regenerating rat liver2005Inngår i: Journal of Hepatology, ISSN 0168-8278, E-ISSN 1600-0641, Vol. 43, nr 3, s. 478-484Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background/Aims: The synthetic estrogen 17 alpha-ethinyl estradiol (EE), a potent tumor promoter in rat liver, stimulates growth during short-term treatment but inhibits hepatocyte proliferation upon prolonged treatment. To identify the molecular targets of the mitoinhibitory effect of EE, the expression of proteins regulating G(1)- and S-progression were analyzed during the first cell cycle in EE-treated female Wistar rats. Methods: Long-term (60 days) EE treatment. Immunohistochemical staining for proliferation cell nuclear antigen (PCNA) to detect cells in S phase and quantification of mitosis. Western blot to monitor protein expression. Cdk2 kinase assay to examine histone H1 phosphorylation. Results: EE reduced the number of cells in S phase and mitosis by about 70%. Cyclin D-1 and D-3 were unaffected, while cdk4 was moderately decreased. Cyclin E and cdk2 were markedly decreased with concomitant marked reduction of cdk2 kinase activity. EE also decreased cyclin A and increased G(1) levels of p53 and p21. Conclusions: EE causes a cell cycle block before S-phase. The reduction of the cdk2 kinase activity, essential for G(1)/S-transition, might be involved in the cell cycle block. Also, EE treatment results in p53 activation and upregulation of the cdk inhibitor p21 that might contribute to the G(1) arrest.

  • 390.
    Krantz-Frid, Madelene
    Södertörns högskola, Institutionen för livsvetenskaper.
    Ecotoxicological effects from three antifouling paints on the red macroalga Ceramium tenuicorne.2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Antifouling paints are applied on vessels to prevent growth of fouling organisms such hasbarnacles. Presently, there are a number of different paints available on the Swedish marketwith different strategies and active substances. The paints might work by either continuouslyreleasing biocides or physically by peeling off or provide an easily cleansed surface whereorganisms cannot attach. The physically working paints do not need to register an activesubstance since its purpose is not to affect living organisms by a chemical or biological modeof action. In this study, two commercially available paints, the copper-based Fabi 3959(International Paint Ltd) and physically eroding, biocide-free labelled Mille Light (HempelFärg AB) were compared to Hard Racing superior, containing copper and the forbiddensubstance Tributyltin. Fabi International is only allowed to be used on the Swedish west coastdue to 6% added as active substance while the biocide-free Mille Light is eligible for eastcoast usage. The toxic effect from respective paint was investigated by assembling a growthinhibition test with the red macro alga Ceramium tenuicorne. The results show that all thestudied paints had a negative effect on growth and therefore leaked substances inconcentrations high enough to be harmful to the alga. The toxic response differed with theeffect on growth being in the following order, Hard racing superior>Fabi >Mille Light.Implications regarding the current legalization involving biocide-free labelled antifoulingpaints are discussed.

    Fulltekst (pdf)
    FULLTEXT02
  • 391. Kussak, Anders
    et al.
    Weintraub, A
    Quadrupole ion-trap mass spectrometry to locate fatty acids on lipid A from Gram-negative bacteria2002Inngår i: Analytical Biochemistry, ISSN 0003-2697, E-ISSN 1096-0309, Vol. 307, nr 1, s. 131-137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The structure of lipid A released by mild acid hydrolysis from lipopolysaccharide from two strains of Shigella flexneri with different degrees of acylation was characterized using electrospray ionization (ESI) and ion-trap mass spectrometry. The lipid A was analyzed underivatized with ESI in negative-ion mode. With multiple stages of fragmentation (MSn), both the degree of acylation and the positions of the fatty acids on the disaccharide backbone could be determined. It was possible to determine the degree of acylation by the MSn technique, where in each MS stage the parent ion was an ion where one fatty acid had been eliminated. One way to determine the location of the fatty acids was by identifying cross-ring fragments of the reducing sugar from parent ions containing different numbers of fatty acids. Another was by identifying a possible charge-driven release of fatty acids situated close to a phosphate group. The fatty acids were otherwise eliminated by a charge-remote fragmentation mechanism. The combined data show the usefulness of ion-trap mass spectrometers for this type of analysis.

  • 392.
    Kärblane, Kairi
    et al.
    Tallinn University of Technology, Tallinn, Estonia / Competence Centre for Cancer Research, Tallinn, Estonia .
    Gerassimenko, Jelena
    Tallinn University of Technology, Tallinn, Estonia / Competence Centre for Cancer Research, Tallinn, Estonia .
    Nigul, Lenne
    Tallinn University of Technology, Tallinn, Estonia.
    Piirsoo, Alla
    Tallinn University of Technology, Tallinn, Estonia.
    Smialowska, Agata
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik. Karolinska Institutet.
    Vinkel, Kadri
    Tallinn University of Technology, Tallinn, Estonia .
    Kylsten, Per
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik.
    Ekwall, Karl
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik. Karolinska Institutet.
    Swoboda, Peter
    Karolinska Institutet.
    Truve, Erkki
    Tallinn University of Technology, Tallinn, Estonia / Competence Centre for Cancer Research, Tallinn, Estonia .
    Sarmiento, Cecilia
    Tallinn University of Technology, Tallinn, Estonia / Competence Centre for Cancer Research, Tallinn, Estonia .
    ABCE1 Is a Highly Conserved RNA Silencing Suppressor2015Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 10, nr 2, artikkel-id e0116702Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    ATP-binding cassette sub-family E member 1 (ABCE1) is a highly conserved protein among eukaryotes and archaea. Recent studies have identified ABCE1 as a ribosome-recycling factor important for translation termination in mammalian cells, yeast and also archaea. Here we report another conserved function of ABCE1. We have previously described AtRLI2, the homolog of ABCE1 in the plant Arabidopsis thaliana, as an endogenous suppressor of RNA silencing. In this study we show that this function is conserved: human ABCE1 is able to suppress RNA silencing in Nicotiana benthamiana plants, in mammalian HEK293 cells and in the worm Caenorhabditis elegans. Using co-immunoprecipitation and mass spectrometry, we found a number of potential ABCE1-interacting proteins that might support its function as an endogenous suppressor of RNA interference. The interactor candidates are associated with epigenetic regulation, transcription, RNA processing and mRNA surveillance. In addition, one of the identified proteins is translin, which together with its binding partner TRAX supports RNA interference.

  • 393.
    Kärnefelt, Ingvar
    et al.
    Lunds universitet.
    Mattsson, Jan-Eric
    Lunds universitet.
    Thell, Arne
    Lunds universitet.
    Evolution and phylogeny of cetrarioid lichens1992Inngår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 183, nr 1-2, s. 113-160Artikkel i tidsskrift (Fagfellevurdert)
  • 394.
    Kärnefelt, Ingvar
    et al.
    Lunds universitet.
    Mattsson, Jan-Eric
    Lunds universitet.
    Thell, Arne
    Lunds universitet.
    The lichen genera Arctocetraria, Cetraria, and Cetrariella (Parmeliaceae) and their presumed evolutionary affinities1993Inngår i: The Bryologist, ISSN 0007-2745, E-ISSN 1938-4378, nr 96, s. 394-404Artikkel i tidsskrift (Fagfellevurdert)
  • 395.
    König, Malin A E
    et al.
    Stockholm University.
    Lehtilä, Kari
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Wiklund, Christer
    Stockholm University.
    Ehrlén, Johan
    Stockholm University.
    Among-Population Variation in Tolerance to Larval Herbivory by Anthocharis cardamines in the Polyploid Herb Cardamine pratensis2014Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 9, nr 6, s. e99333-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Plants have two principal defense mechanisms to decrease fitness losses to herbivory: tolerance, the ability to compensate fitness after damage, and resistance, the ability to avoid damage. Variation in intensity of herbivory among populations should result in variation in plant defense levels if tolerance and resistance are associated with costs. Yet little is known about how levels of tolerance are related to resistance and attack intensity in the field, and about the costs of tolerance. In this study, we used information about tolerance and resistance against larval herbivory by the butterfly Anthocharis cardamines under controlled conditions together with information about damage in the field for a large set of populations of the perennial plant Cardamine pratensis. Plant tolerance was estimated in a common garden experiment where plants were subjected to a combination of larval herbivory and clipping. We found no evidence of that the proportion of damage that was caused by larval feeding vs. clipping influenced plant responses. Damage treatments had a negative effect on the three measured fitness components and also resulted in an earlier flowering in the year after the attack. Tolerance was related to attack intensity in the population of origin, i.e. plants from populations with higher attack intensity were more likely to flower in the year following damage. However, we found no evidence of a relationship between tolerance and resistance. These results indicate that herbivory drives the evolution for increased tolerance, and that changes in tolerance are not linked to changes in resistance. We suggest that the simultaneous study of tolerance, attack intensity in the field and resistance constitutes a powerful tool to understand how plant strategies to avoid negative effects of herbivore damage evolve.

  • 396. Laikre, Linda
    et al.
    Jonsson, Bengt-Gunnar
    Ihse, Margareta
    Marissink, Mark
    Gustavsson, Ann-Marie Dock
    Ebenhard, Torbjörn
    Hagberg, Lovisa
    Stål, Par-Olof
    von Walter, Susanne
    Wramner, Per
    Södertörns högskola, Institutionen för livsvetenskaper, Coastal Management Research Center (COMREC).
    Wanted: Scientists in the CBD process2008Inngår i: Conservation Biology, ISSN 0888-8892, E-ISSN 1523-1739, Vol. 22, nr 4, s. 814-815Artikkel i tidsskrift (Fagfellevurdert)
  • 397. Landberg, Katarina
    et al.
    Nilsson, Lars
    Para, Alessia
    Uppsala universitet, Fysiologisk botanik.
    Sundås Larsson, Annika
    Södertörns högskola, Avdelning Naturvetenskap.
    The TERMINAL FLOWER2 (TFL2) Gene Regulates the Transition to Flowering by Repressing Gene ActivityManuskript (preprint) (Annet vitenskapelig)
  • 398.
    Landerholm, Malin K
    et al.
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Li, J J
    Richards, J C
    Hood, D W
    Moxon, E R
    Schweda, Elke K H
    Södertörns högskola, Institutionen för kemi, biologi, geografi och miljövetenskap.
    Characterization of novel structural features in the lipopolysaccharide of nondisease associated nontypeable Haemophilus influenzae2004Inngår i: European Journal of Biochemistry, ISSN 0014-2956, E-ISSN 1432-1033, Vol. 271, nr 5, s. 941-953Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nontypeable Haemophilus influenzae (NTHi) is a common commensal of the human upper respiratory tract and is associated with otitis media in children. The structures of the oligosaccharide portions of NTHi lipopolysaccharide (LPS) from several otitis media isolates are now well characterized but it is not known whether there are structural differences in LPS from colonizing, nondisease associated strains. Structural analysis of LPS from nondisease associated NTHi strains 11 and 16 has been achieved by the application of high-field NMR techniques, ESI-MS, ESI-MSn, capillary electrophoresis coupled to ESI-MS, composition and linkage analyses on O-deacylated LPS and core oligosaccharide material. This is the first study to report structural details on LPS from strains taken from the nasopharynx from healthy individuals. Both strains express identical structures and contain the common element of H. influenzae LPS, L-alpha-D-Hepp-(1-->2)-[PEtn-->6]-L-alpha-D-Hepp-(1-->3)-[beta-D-Glcp-(1 -->4)]-L-alpha-D-Hepp-(1-->5)-[PPEtn-->4]-alpha-Kdop-(2-->6)-lipid A, in which each heptose is elongated by a single hexose residue with no further oligosaccharide extensions. In the major Hex3 glycoform, the terminal Hepp residue (HepIII) is substituted at the O-2 position by a beta-D-Galp residue and the central Hepp residue (HepII) is substituted at O-3 by a alpha-D-Glcp residue. Notably, the strains express two phosphocholine (PCho) substituents, one at the O-6 position of alpha-D-Glcp and the other at the O-6 position of beta-D-Galp. Major acetylation sites were identified at O-4 of Gal and O-3 of HepIII. Additionally, both strains express glycine, and strain 11 also expresses detectable amounts of N-acetylneuraminic acid.

  • 399. Langefors, Åsa
    et al.
    Lohm, Jakob
    von Schantz, Torbjörn
    Grahn, Mats
    Södertörns högskola, Avdelning Naturvetenskap.
    Screening of Mhc variation in Atlantic salmon (Salmo salar): a comparison of restriction fragment length polymorphism (RFLP), denaturing gradient gel electrophoresis (DGGE) and sequencing2000Inngår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 9, nr 2, s. 215-219Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We compared three different molecular methods currently used for screening of Mhc variation in population studies of Atlantic salmon. Restriction fragment length polymorphism (RFLP) of the entire class II gene detected 22 haplotypes. Seventeen exon 2 sequences were obtained from individuals carrying the 22 haplotypes, two of which had not been detected by RFLP. The six alleles (27%) detected by RFLP and not by exon 2 sequencing probably resulted from sequence variation outside exon 2. Within exon 2, RFLP differentiated 88% of the sequences. Alternatively, denaturing gradient gel electrophoresis (DGGE) performed under two run conditions detected 94% of the sequence variation. Both RFLP using different probes, and the two PCR-based methods using three different primer pairs, suggest that there is only a single Mhc class II B gene in the Baltic populations of Atlantic salmon.

  • 400.
    Larsson, Josefine
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Genetic Aspects of Environmental Disturbances in Marine Ecosystems: Studies of the Blue Mussel in the Baltic Sea2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Anthropogenic environmental changes can serve as drivers for evolutionary responses in wild populations. To predict the long-term impact of anthropogenic changes on populations, it is crucial to understand the genetic effects caused by these disturbances. The Baltic Sea is considered to be one of the world’s most contaminated seas, and the increase of anthropogenic chemical pollution is a major threat to its ecosystems. This thesis assesses the impact of harbors and sewage treatment plants on physiological traits and genetic structure of resident populations of blue mussels at replicated sites in the Baltic Sea. The initial evaluation of the overall genetic pattern in blue mussel populations in the Swedish West Coast, the Baltic Proper and the Bothnian Sea found genetic differentiation between the three water basins and a low genetic differentiation within each basin, especially within the Baltic Proper. Despite the low genetic differentiation among blue mussels within the Baltic Proper, a parallel genetic differentiation associated with sewage treatment plant effluents was found in this basin. This included genomic regions with a high degree of differentiation between reference sites and sites affected by sewage plants effluent. This genetic differentiation is suggested to be due to post-dispersal selection acting in each generation. In contrast, no parallel genetic differentiation was associated with harbors. We identified five genomic regions in blue mussels, showing strong signs of selection, shared among three out of four replicated reference sites and sites affected by sewage effluents in the Baltic Proper i.e. Askö, Tvärminne and Karlskrona. An initial characterization of these genomic regions revealed functions related to immune and endocrine responses, oxidative stress and shell formation. Our results indicate that selection caused by sewage effluents involves multiple loci. The same genomic regions are found across different locations in the Baltic Proper but there are also unique genomic regions at each location. No genotoxic or histopathological effects were found among blue mussels from sewage effluent-affected areas but a higher frequency of histological abnormalities in the digestive gland were observed in mussels from harbors.

    Fulltekst (pdf)
    Genetic Aspects of Environmental Disturbances in Marine Ecosystems: Studies of the Blue Mussel in the Baltic Sea
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