Set1 is required for meiotic S-phase onset, double-strand break formation and middle gene expression.

ABSTRACT: The Set1 protein of Saccharomyces cerevisiae is a histone methyltransferase (HMTase) acting on lysine 4 of histone H3. Inactivation of the SET1 gene in a diploid leads to a sporulation defect. We have studied various processes that take place during meiotic differentiation in set1delta diploid cells. The absence of Set1 leads to a delay of meiotic S-phase onset, which reflects a defect in DNA replication initiation. The timely induction of meiotic DNA replication does not require the Set1 HMTase activity, but depends on the SET domain. In addition, set1delta displays a severe impairment of the DNA double-strand break formation, which is not only the consequence of the replication delay. Transcriptional profiling experiments show that the induction of middle meiotic genes, but not of early

SUBMITTER: Sollier J 

PROVIDER: S-EPMC404324 | biostudies-literature | 2004 May

REPOSITORIES: biostudies-literature