a role for set1mll-related components in epigenetic regulation of the caenorhabditis elegans germ lineset1mll-related组件的作用的表观遗传调控线虫种系.pdfVIP

A Role for Set1/MLL-Related Components in Epigenetic Regulation of the Caenorhabditis elegans Germ Line 1,2 1 Tengguo Li , William G. Kelly * 1 Biology Department, Rollins Research Center, Emory University, Atlanta, Georgia, United States of America, 2 Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, Georgia, United States of America Abstract The methylation of lysine 4 of Histone H3 (H3K4me) is an important component of epigenetic regulation. H3K4 methylation is a consequence of transcriptional activity, but also has been shown to contribute to ‘‘epigenetic memory’’; i.e., it can provide a heritable landmark of previous transcriptional activity that may help promote or maintain such activity in subsequent cell descendants or lineages. A number of multi-protein complexes that control the addition of H3K4me have been described in several organisms. These Set1/MLL or COMPASS complexes often share a common subset of conserved proteins, with other components potentially contributing to tissue-specific or developmental regulation of the methyltransferase activity. Here we show that the normal maintenance of H3K4 di- and tri-methylation in the germ line of Caenorhabditis elegans is dependent on homologs of the Set1/MLL complex components WDR-5.1 and RBBP-5. Different methylation states that are each dependent on wdr-5.1 and rbbp-5 require different methyltransferases. In addition, different subsets of conserved Set1/MLL-like complex components appear to be required for H3K4 methylation in germ cells and somatic lineages at different developmental stages. In adult germ cells, mutations in wdr-5.1 or rbbp-5 dramatically affect both germ line stem cell (GSC) population size and proper germ cell development. RNAi kn