A NASP (N1/N2)-related protein, Sim3, binds CENP-A and is required for its deposition at fission yeast Centromeres
2007 (English)In: Molecular Cell, ISSN 1097-2765, E-ISSN 1097-4164, Vol. 28, no 6, 1029-1044 p.Article in journal (Refereed) Published
A defining feature of centromeres is the presence of the histone H3 variant CENP-A(Cnp1). It is not known how CENP-A(Cnp1) is specifically delivered to, and assembled into, centromeric chromatin. Through a screen for factors involved in kinetochore integrity in fission yeast, we identified Sim3. Sim3 is homologous to known histone binding proteins NASP(Human) and N1/N2(Xenopus) and aligns with Hif1(S. cerevisiae), defining the SHNi-TPR family. Sim3 is distributed throughout the nucleoplasm, yet it associates with CENP-A(Cnp1) and also binds H3. Cells defective in Sim3 function have reduced levels of CENP-A(CnP1) at centromeres (and increased H3) and display chromosome segregation defects. Sim3 is required to allow newly synthesized CENP-A(Cnp1) to accumulate at centromeres in S and G2 phase-arrested cells in a replication-independent mechanism. We propose that one function of Sim3 is to act as an escort that hands off CENP-A(Cnp1) to chromatin assembly factors, allowing its incorporation into centromeric chromatin.
Place, publisher, year, edition, pages
2007. Vol. 28, no 6, 1029-1044 p.
Biochemistry and Molecular Biology
IdentifiersURN: urn:nbn:se:sh:diva-22599DOI: 10.1016/j.molcel.2007.10.010ISI: 000252170000010PubMedID: 18158900ScopusID: 2-s2.0-37449024145OAI: oai:DiVA.org:sh-22599DiVA: diva2:700074