Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

TY - JOUR

T1 - Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

AU - Willer, M

AU - Hoffmann, Ulla-Lisbeth

AU - Styrkársdóttir, U

AU - Egel, R

AU - Davey, William John

AU - Nielsen, O

AU - Nielsen, Olaf

PY - 1995/9/1

Y1 - 1995/9/1

N2 - 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.

AB - 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.

KW - Base Sequence

KW - Fungal Proteins

KW - Gene Expression Regulation, Fungal

KW - Genes, Fungal

KW - Meiosis

KW - Models, Biological

KW - Molecular Sequence Data

KW - Peptides

KW - Pheromones

KW - Reproduction

KW - Schizosaccharomyces

KW - Schizosaccharomyces pombe Proteins

KW - Signal Transduction

KW - Transcription, Genetic

M3 - Journal article

C2 - 7651414

SN - 0270-7306

VL - 15

SP - 4964

EP - 4970

JO - Molecular and Cellular Biology

JF - Molecular and Cellular Biology

IS - 9

ER -