Project description:Here, we report the high-throughput profiling of histone modification (H3K9me2) in fission yeast Schizosaccharomyces pombe. We generated genome-wide H3K9me2 maps of fission yeast mutants in swo1-26 (temperature sensitive, ts) cells at 25℃ and 37℃. We find that H3K9me2 enrichment at heterochromatin regions, especially at the mating-type locus and subtelomeres, is compromised, suggesting heterochromatin assembly defects.
Project description:RNA interference (RNAi) is a gene silencing mechanism conserved from fungi to mammals. Small interfering RNAs are products and mediators of the RNAi pathway and act as specificity factors in recruiting effector complexes. The Schizosaccharomyces pombe genome encodes one of each of the core RNAi proteins, Dicer, Argonaute and RNA-dependent RNA polymerase (dcr1, ago1, rdp1). Even though the function of RNAi in heterochromatin assembly in S. pombe is established, its role in controlling gene expression is elusive. Here, we report the identification of small RNAs mapped anti-sense to protein coding genes in fission yeast. We demonstrate that these genes are up-regulated at the protein level in RNAi mutants, while their mRNA levels are not significantly changed. We show that the repression by RNAi is not a result of heterochromatin formation. Thus, we conclude that RNAi is involved in post-transcriptional gene silencing in S. pombe.
