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  • 1. Agianian, Bogos
    et al.
    Lesch, Christine
    Loseva, Olga
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences. Uppsala University.
    Preliminary characterization of hemolymph coagulation in Anopheles gambiae larvae2007In: Developmental and Comparative Immunology, ISSN 0145-305X, E-ISSN 1879-0089, Vol. 31, no 9, p. 879-888Article in journal (Refereed)
    Abstract [en]

    Hemolymph coagulation is a first response to injury, impeding infection, and ending bleeding. Little is known about its molecular basis in insects, but clotting factors have been identified in the fruit fly Drosophila melanogaster. Here, we have begun to study coagulation in the aquatic larvae of the malaria vector mosquito Anopheles gambiae using methods developed for Drosophila. A delicate clot was seen by light microscopy, and pullout and proteomic analysis identified phenoloxidase and apolipophorin-I as major candidate clotting factors. Electron microscopic analysis confirmed clot formation and revealed it contains fine molecular sheets, most likely a result of lipophorin assembly. Phenoloxidase appears to be more critical in clot formation in Anopheles than in Drosophila. The Anopheles larval clot thus differs in formation, structure, and composition from the clot in Drosophila, confirming the need to study coagulation in different insect species to learn more about its evolution and adaptation to different lifestyles.

  • 2.
    Bidla, Gawa
    et al.
    Stockolms universitet.
    Lindgren, Malin
    Södertörn University, School of Life Sciences.
    Theopold, Ulrich
    Stockholms universitet.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences.
    Hemolymph coagulation and phenoloxidase in Drosophila larvae2005In: Developmental and Comparative Immunology, ISSN 0145-305X, E-ISSN 1879-0089, Vol. 29, no 8, p. 669-679Article in journal (Refereed)
    Abstract [en]

    Hemolymph coagulation is a first response to wounding in insects. Although studies have been performed in large-bodied insects such as the moth Galleria mellonella, less is known about clotting in Drosophila melanogaster, the insect most useful for genetic and molecular analyses of innate immunity. Here we show the similarities between clots in Drosophila and Galleria by light- and electron microscopy. Phenoloxidase changes the Drosophila clot's physical properties through cross-linking and melanization, but it is not necessary for preliminary soft clot formation. Bacteria associate with the clot, but this alone does not necessarily kill them. The stage is now set for rapid advances in our understanding of insect hemolymph coagulation, its roles in immune defense and wound healing, and for a more comprehensive grasp of the insect immune system in general.

  • 3.
    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
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    Schmidt, O
    University of Adelaide, Glen Osmond, South Australia.
    Ueda, R
    National Institute of Genetics, Shizuoka, Japan.
    Dushay, Mitchell S
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    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 bacteria2004In: Insect Biochemistry and Molecular Biology, ISSN 0965-1748, E-ISSN 1879-0240, Vol. 34, no 12, p. 1297-1304Article in journal (Refereed)
    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.

  • 4.
    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
    Södertörn University, School of Life Sciences. Stockholms universitet.
    Loseva, Olga
    Stockholms universitet.
    Schmidt, Otto
    University of Adelaide, Glen Osmond, Australia.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences. Uppsala University.
    Theopold, Ulrich
    Stockholms universitet.
    Evidence for an immune function of lepidopteran silk proteins2007In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 352, no 2, p. 317-322Article in journal (Refereed)
    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.

  • 5.
    Lesch, Christine
    et al.
    Stockholms universitet.
    Goto, Akira
    UPR9022 du CNRS, IBMC, Strasbourg, France.
    Lindgren, Malin
    Södertörn University, School of Life Sciences.
    Bidla, Gawa
    Stockholms universitet.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences. Uppsala University.
    Theopold, Ulrich
    Stockholms universitet.
    A role for Hemolectin in coagulation and immunity in Drosophila melanogaster2007In: Developmental and Comparative Immunology, ISSN 0145-305X, E-ISSN 1879-0089, Vol. 31, no 12, p. 1255-1263Article in journal (Refereed)
    Abstract [en]

    Hemolectin has been identified as a candidate clotting factor in Drosophila. We reassessed the domain structure of Hemolectin (Hml) and propose that instead of C-type lectin domains, the two discoidin domains are most likely responsible for the protein's lectin activity. We also tested Hml's role in coagulation and immunity in Drosophila. Here we describe the isolation of a new hml allele in a forward screen for coagulation mutants, and our characterization of this and two other hml alleles, one of which is a functional null. While loss of Hml had strong effects on larval hemolymph coagulation ex vivo, mutant larvae survived wounding. Drosophila thus possesses redundant hemostatic mechanisms. We also found that loss of Hml in immune-handicapped adults rendered them more sensitive to Gram(-) bacteria infection. This demonstrates an immunological role of this clotting protein and reinforces the importance of the clot in insect immunity.

  • 6.
    Lindgren, Malin
    et al.
    Södertörn University, School of Life Sciences.
    Riazi, Raha
    Stockholms universitet.
    Lesch, Christine
    Stockholms universitet.
    Willielinsson, Christine
    Stockholms universitet.
    Theopold, Ulrich
    Stockholms universitet.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences.
    Fondue and transglutaminase in the Drosophila larval clot2008In: Journal of insect physiology, ISSN 0022-1910, E-ISSN 1879-1611, Vol. 54, no 3, p. 586-592Article in journal (Refereed)
    Abstract [en]

    Hemolymph coagulation is vital for larval hemostasis and important in immunity, yet the molecular basis of coagulation is not well understood in insects. Of the larval clotting factors identified in Drosophila, Fondue is not conserved in other insects, but is notable for its effects on the clot's physical properties.. a possible function in the cuticle, and for being a substrate of transglutaminase. Transglutaminase is the only mammalian clotting factor found in Drosophila, and as it acts in coagulation in other invertebrates, it is also likely to be important in clotting in Drosophila. Here we describe a Fondue-GFP fusion construct that labels the cuticle and clot, and show that chemical inhibition and RNAi knockdown of the Drosophila transglutaminase gene affect clot properties and composition in ways similar to knockdown of the fon gene. Thus, Fondue appears to be incorporated into the cuticle and is a key transglutaminase substrate in the clot. This is also the first direct functional confirmation that transglutaminase acts in coagulation in Drosophila.

  • 7.
    Markovic, Maja Pavlovic
    et al.
    Södertörn University, School of Life Sciences.
    Kylsten, Per
    Södertörn University, School of Life Sciences, Molecular biology.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences.
    Drosophila lamin mutations cause melanotic mass formation and lamellocyte differentiation2009In: Molecular Immunology, ISSN 0161-5890, E-ISSN 1872-9142, Vol. 46, no 16, p. 3245-3250Article in journal (Refereed)
    Abstract [en]

    The fruit fly immune system is a valuable model for invertebrate and innate immunity. Cellular immune reactions in Drosophila are of great interest, especially the molecular genetic mechanisms of hemocyte differentiation and the encapsulation of foreign bodies. Here we report that changes in the lamin gene cause melanotic masses. These darkened clusters of cells result from autoimmune-like encapsulation of self-tissue, as shown by the presence in lam larvae of lamellocytes, effector hemocytes that appear in larvae following wounding or parasitization. Lamins thus affect immunity in Drosophila, and lam mutations can serve as genetic tools to dissect cellular immune signaling and effector pathways.

  • 8.
    Munoz-Alarcon, Andres
    et al.
    Södertörn University, School of Life Sciences. Karolinska Institute.
    Pavlovic, Maja
    Södertörn University, School of Life Sciences. Karolinska Institute.
    Wismar, Jasmine
    Max-Planck-Institut für Hirnforschung, Frankfurt, Germany.
    Schmitt, Bertram
    Max-Planck-Institut für Hirnforschung, Frankfurt, Germany.
    Eriksson, Maria
    Karolinska Institute.
    Kylsten, Per
    Södertörn University, School of Life Sciences.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences. Uppsala University.
    Characterization of lamin Mutation Phenotypes in Drosophila and Comparison to Human Laminopathies2007In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, no 6, p. e532-Article in journal (Refereed)
    Abstract [en]

    Lamins are intermediate filament proteins that make up the nuclear lamina, a matrix underlying the nuclear membrane in all metazoan cells that is important for nuclear form and function. Vertebrate A-type lamins are expressed in differentiating cells, while B-type lamins are expressed ubiquitously. Drosophila has two lamin genes that are expressed in A-and B-type patterns, and it is assumed that similarly expressed lamins perform similar functions. However, Drosophila and vertebrate lamins are not orthologous, and their expression patterns evolved independently. It is therefore of interest to examine the effects of mutations in lamin genes. Mutations in the mammalian lamin A/C gene cause a range of diseases, collectively called laminopathies, that include muscular dystrophies and premature aging disorders. We compared the sequences of lamin genes from different species, and we have characterized larval and adult phenotypes in Drosophila bearing mutations in the lam gene that is expressed in the B-type pattern. Larvae move less and show subtle muscle defects, and surviving lam adults are flightless and walk like aged wild-type flies, suggesting that lam phenotypes might result from neuromuscular defects, premature aging, or both. The resemblance of Drosophila lam phenotypes to human laminopathies suggests that some lamin functions may be performed by differently expressed genes in flies and mammals. Such still-unknown functions thus would not be dependent on lamin gene expression pattern, suggesting the presence of other lamin functions that are expression dependent. Our results illustrate a complex interplay between lamin gene expression and function through evolution.

  • 9. Scherfer, C
    et al.
    Karlsson, C
    Loseva, O
    Bidla, G
    Goto, A
    Havemann, J
    Dushay, Mitchell S
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    Theopold, U
    Isolation and characterization of hemolymph clotting factors in Drosophila melanogaster by a pullout method2004In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 14, no 7, p. 625-629Article in journal (Refereed)
    Abstract [en]

    Clotting is critical in limiting loss of hemolymph and initiating wound healing in insects as well as in vertebrates [1]. Clotting is also an important immune defense, quickly forming a secondary barrier to infection, thereby immobilizing, and possibly killing bacteria directly [2, 3]. Here, we describe methods to assess clotting and to extract the clot from Drosophila larval hemolymph by using aggregation of paramagnetic beads. The validity of the assay was demonstrated by characterization of mutants. We show that clotting occurs in the absence of phenoloxidase and that the Drosophila clot binds bacteria. We also describe a pullout assay to purify the clot as a whole, free from entrapped hemocytes and cellular debris. Proteins subsequently identified by mass spectrometry include both predicted and novel clot proteins. Immune induction has been shown for three of the latter, namely Tiggrin and two unknown proteins (GC15825 and CG15293) [4,5] that we now propose function in hemolymph clotting. The most abundant clot protein is Hemolectin [6], and we confirm that hemolectin mutant larvae show clotting defects.

  • 10. Scherfer, Christoph
    et al.
    Qazi, Mousumi R.
    Takahashi, Kuniaki
    Ueda, Ryu
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences.
    Theopold, Ulnich
    Lemaitre, Bruno
    The Toll immune-regulated Drosophila protein Fondue is involved in hemolymph clotting and puparium formation2006In: Developmental Biology, ISSN 0012-1606, E-ISSN 1095-564X, Vol. 295, no 1, p. 156-163Article in journal (Refereed)
    Abstract [en]

    Clotting is critical in limiting hemolymph loss and initiating wound healing in insects as in vertebrates. It is also an important immune defense, quickly forming a secondary barrier to infection, immobilizing bacteria and thereby promoting their killing. However, hemolymph clotting is one of the least understood immune responses in insects. Here, we characterize fondue (fon; CG15825), an immune-responsive gene of Drosophila melanogaster that encodes an abundant hemolymph protein containing multiple repeat blocks. After knockdown of fon by RNAi, bead aggregation activity of larval hemolymph is strongly reduced, and wound closure is affected. Jon is thus the second Drosophila gene after hemolectin (hml), for which a knockdown causes a clotting phenotype. In contrast to hml-RNAi larvae, clot fibers are still observed in samples from fon-RNAi larvae. However, clot fibers from fon-RNAi larvae are more ductile and longer than in wt hemolymph samples, indicating that Fondue might be involved in cross-linking of fiber proteins. In addition, fon-RNAi larvae exhibit melanotic tumors and constitutive expression of the antifungal peptide gene Drosomycin (Drs), while fon-RNAi pupae display an aberrant pupal phenotype. Altogether, our studies indicate that Fondue is a major hemolymph protein required for efficient clotting in Drosophila.

  • 11. Theopold, U
    et al.
    Schmidt, O
    Söderhäll, K
    Dushay, Mitchell S
    Södertörn University, School of Chemistry, Biology, Geography and Environmental Science.
    Coagulation in arthropods: defence, wound closure and healing2004In: Trends in immunology, ISSN 1471-4906, E-ISSN 1471-4981, Vol. 25, no 6, p. 289-294Article in journal (Refereed)
    Abstract [en]

    Arthropods have open circulatory systems and must seal wounds and keep bacteria from entering the hemocoel using efficient clotting systems. Enzymes that crosslink the clot include transglutaminase, which is phylogenetically conserved, and phenoloxidase, which is not found in vertebrates. Prophenoloxidase is usually activated through a proteolytic cascade similar to the vertebrate clotting cascade. The well-characterized clotting cascade in horseshoe crabs is strongly activated by bacterial elicitors, in contrast to vertebrate clotting where induction relies more on endogenous signals. Many arthropod clotting factors are not orthologues of blood clotting factors, but show novel architectures assembled from domains that are also found in their vertebrate counterparts. The cellular mechanisms that lead to coagulation of blood and hemolymph appear to be similar. Recent findings in Drosophila reveal parallels between developmental processes that involve epithelial fusion and wound healing, enabling genetic dissection of the signal pathways involved. This Review is the first in a series on interactions between haemostasis and inflammation.

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