Repression of Germline Genes in Caenorhabditis elegans Somatic Tissues by H3K9 Dimethylation of Their Promoters

and DREAM complex mutants likely represents a difference in molecular function for these synMuv B proteins. In support of the pivotal role of H3K9me2 in regulation of germline genes by LIN-15B, global loss of H3K9me2 but not H3K9me3 results in phenotypes similar to synMuv B mutants, high-temperature larval arrest, and ectopic expression of germline genes in the soma. We propose that LIN-15B-driven enrichment of H3K9me2 at promoters of germline genes contributes to repression of those genes in somatic tissues.