Analysis of the structural genes encoding M-factor in the fission yeast Schizosaccharomyces pombe: identification of a third gene, mfm3.
We previously identified two genes, mfm1 and mfm2, with the potential to encode the M-factor mating pheromone of the fission yeast Schizosaccharomyces pombe (J. Davey, EMBO J. 11:951-960, 1992), but further analysis revealed that a mutant strain lacking both genes still produced active M-factor. Here we describe the isolation and characterization of a third M-factor gene, mfm3. A mutant lacking all three genes fails to produce M-factor, indicating that all functional M-factor genes now have been identified. The triple mutant exhibits an absolute mating defect in M cells, a defect that is not rescued by addition of exogenous M-factor. A mutational analysis reveals that all three mfm genes contribute to the production of M-factor. Their transcription is limited to M cells and requires the mat1-Mc and ste11 gene products. Each gene is induced when the cells are starved of nitrogen and further induced by a pheromone signal. Additionally, the signal transduction machinery associated with the pheromone response is required for transcription of the mfm genes in both stimulated and unstimulated cells.
Kjaerulff
S
S
Department of Genetics, University of Copenhagen, Denmark.
Davey
J
J
Nielsen
O
O
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D017931:DNA Primers; D005800:Genes, Fungal; D000072235:Mating Factor; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016366:Open Reading Frames; D010452:Peptide Biosynthesis; D010455:Peptides / Q000235:genetics*; D010675:Pheromones / Q000235:genetics; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D012568:Schizosaccharomyces / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D017931:DNA Primers; D010455:Peptides; D010675:Pheromones; D000072235:Mating Factor