title: Repression of meiotic genes by antisense transcription and by Fkh2 transcription factor in Schizosaccharomyces pombe.
abstract: In S. pombe, about 5% of genes are meiosis-specific and accumulate little or no mRNA during vegetative growth. Here we use Affymetrix tiling arrays to characterize transcripts in vegetative and meiotic cells. In vegetative cells, many meiotic genes, especially those induced in mid-meiosis, have abundant antisense transcripts. Disruption of the antisense transcription of three of these mid-meiotic genes allowed vegetative sense transcription. These results suggest that antisense transcription represses sense transcription of meiotic genes in vegetative cells. Although the mechanism(s) of antisense mediated transcription repression need to be further explored, our data indicates that RNAi machinery is not required for repression. Previously, we and others used non-strand specific methods to study splicing regulation of meiotic genes and concluded that 28 mid-meiotic genes are spliced only in meiosis. We now demonstrate that the "unspliced" signal in vegetative cells comes from the antisense RNA, not from unspliced sense RNA, and we argue against the idea that splicing regulates these mid-meiotic genes. Most of these mid-meiotic genes are induced in mid-meiosis by the forkhead transcription factor Mei4. Interestingly, deletion of a different forkhead transcription factor, Fkh2, allows low levels of sense expression of some mid-meiotic genes in vegetative cells. We propose that vegetative expression of mid-meiotic genes is repressed at least two independent ways: antisense transcription and Fkh2 repression.
authors.affiliation: Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America.
authors.forename: Huei-Mei
authors.initials: HM
authors.lastname: Chen
authors.forename: Adam P
authors.initials: AP
authors.lastname: Rosebrock
authors.forename: Sohail R
authors.initials: SR
authors.lastname: Khan
authors.forename: Bruce
authors.initials: B
authors.lastname: Futcher
authors.forename: Janet K
authors.initials: JK
authors.lastname: Leatherwood
mesh_terms: D001483:Base Sequence; D016000:Cluster Analysis; D015536:Down-Regulation / Q000187:drug effects; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D005800:Genes, Fungal / Q000187:drug effects / Q000235:genetics; D008540:Meiosis / Q000187:drug effects / Q000235:genetics*; D046228:Microarray Analysis; D008969:Molecular Sequence Data; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology*; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: C500536:Fkh2 protein, S pombe; D020319:Oligodeoxyribonucleotides, Antisense; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors