Title: | Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe |
Author(s): | Willer M; Hoffmann L; Styrkarsdottir U; Egel R; Davey J; Nielsen O; |
Address: | "Department of Genetics, University of Copenhagen, Denmark" |
ISSN/ISBN: | 0270-7306 (Print) 1098-5549 (Electronic) 0270-7306 (Linking) |
Abstract: | "The mat1 locus is a key regulator of both conjugation and meiosis in the fission yeast Schizosaccharomyces pombe. Two alternative DNA segments of this locus, mat1-P and mat1-M, specify the haploid cell types (Plus and Minus). Each segment includes two genes: mat1-P includes mat1-Pc and mat1-Pm, while mat1-M includes mat1-Mc and mat1-Mm. The mat1-Pc and mat1-Mc genes are responsible for establishing the pheromone communication system that mediates conjugation between P and M cells, while all four mat1 genes are required for meiosis in diploid P/M cells. Our understanding of the initiation of meiosis is based largely on indirect observations, and a more precise investigation of these events was required to define the interaction between the mat1 genes. Here we resolve this issue using synthetic pheromones and P/M strains with mutations in either mat1-Pc or mat1-Mc. Our results suggest a model in which the mat1 locus plays two roles in controlling meiosis. In the first instance, the mat1-Pc and mat1-Mc functions are required to produce the mating pheromones and receptors that allow the generation of a pheromone signal. This signal is required to induce the expression of mat1-Pm and mat1-Mm. This appears to be the major pheromone-dependent step in controlling meiosis since ectopic expression of these genes allows meiosis in the absence of mat1-Pc and mat1-Mc. The mat1-Pm and mat1-Mm products complete the initiation of meiosis by activating transcription of the mei3 gene" |
Keywords: | "Base Sequence DNA-Binding Proteins Fungal Proteins/genetics *Gene Expression Regulation, Fungal Genes, Fungal Intercellular Signaling Peptides and Proteins Meiosis/*genetics Models, Biological Molecular Sequence Data Peptides/*genetics Pheromones/metaboli;" |
Notes: | "MedlineWiller, M Hoffmann, L Styrkarsdottir, U Egel, R Davey, J Nielsen, O eng Research Support, Non-U.S. Gov't 1995/09/01 Mol Cell Biol. 1995 Sep; 15(9):4964-70. doi: 10.1128/MCB.15.9.4964" |