title: Mmi1 RNA surveillance machinery directs RNAi complex RITS to specific meiotic genes in fission yeast.
abstract: RNA interference (RNAi) silences gene expression by acting both at the transcriptional and post-transcriptional levels in a broad range of eukaryotes. In the fission yeast Schizosaccharomyces pombe the RNA-Induced Transcriptional Silencing (RITS) RNAi complex mediates heterochromatin formation at non-coding and repetitive DNA. However, the targeting and role of RITS at other genomic regions, including protein-coding genes, remain unknown. Here we show that RITS localizes to specific meiotic genes and mRNAs. Remarkably, RITS is guided to these meiotic targets by the RNA-binding protein Mmi1 and its associated RNA surveillance machinery that together degrade selective meiotic mRNAs during vegetative growth. Upon sexual differentiation, RITS localization to the meiotic genes and mRNAs is lost. Large-scale identification of Mmi1 RNA targets reveals that RITS subunit Chp1 associates with the vast majority of them. In addition, loss of RNAi affects the effective repression of sexual differentiation mediated by the Mmi1 RNA surveillance machinery. These findings uncover a new mechanism for recruiting RNAi to specific meiotic genes and suggest that RNAi participates in the control of sexual differentiation in fission yeast.
authors.affiliation: INSERM, U823, Université Joseph Fourier - Grenoble 1, Institut Albert Bonniot, Faculté de Médecine, Domaine de la Merci, La Tronche Cedex, France.
authors.forename: Edwige
authors.initials: E
authors.lastname: Hiriart
authors.forename: Aurélia
authors.initials: A
authors.lastname: Vavasseur
authors.forename: Leila
authors.initials: L
authors.lastname: Touat-Todeschini
authors.forename: Akira
authors.initials: A
authors.lastname: Yamashita
authors.forename: Benoit
authors.initials: B
authors.lastname: Gilquin
authors.forename: Emeline
authors.initials: E
authors.lastname: Lambert
authors.forename: Jonathan
authors.initials: J
authors.lastname: Perot
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Shichino
authors.forename: Nicolas
authors.initials: N
authors.lastname: Nazaret
authors.forename: Cyril
authors.initials: C
authors.lastname: Boyault
authors.forename: Joel
authors.initials: J
authors.lastname: Lachuer
authors.forename: Daniel
authors.initials: D
authors.lastname: Perazza
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamamoto
authors.forename: André
authors.initials: A
authors.lastname: Verdel
mesh_terms: D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D008954:Models, Biological; D011485:Protein Binding; D012331:RNA, Fungal / Q000378:metabolism; D034743:RNA-Induced Silencing Complex / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000235:genetics* / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D039221:mRNA Cleavage and Polyadenylation Factors / Q000378:metabolism*
chemical_list: C512176:Mmi1 protein, S pombe; D012331:RNA, Fungal; D034743:RNA-Induced Silencing Complex; D029702:Schizosaccharomyces pombe Proteins; D039221:mRNA Cleavage and Polyadenylation Factors