Yeast homolog of mammalian mitogen-activated protein kinase, FUS3/DAC2 kinase, is required both for cell fusion and for G1 arrest of the cell cycle and morphological changes by the cdc37 mutation.
Saccharomyces cerevisiae FUS3/DAC2 protein kinase, a homolog of mammalian mitogen-activated protein (MAP) kinase, inactivates a G1 cyclin encoded by the CLN3 gene to arrest cell division in the G1 phase and activates a transcriptional factor STE12 in response to mating pheromone during sexual conjugation. To elucidate the role of the FUS3/DAC2 gene product in the mating process, I constructed and characterized dac2 cln3 double mutants. Here, I show that FUS3/DAC2 is required for completion of cell fusion even in the dac2 cln3 double mutants in which the pheromone response is restored, suggesting that FUS3/DAC2 plays a positive role in cell fusion during conjugation. In addition, the cdc dac2 and cdc37 ste double mutants were constructed and investigated for their phenotypes to clarify the relationship between FUS3/DAC2, STE7 or STE11 and CDC gene products (CDC28, 36, 37 and 39). The results indicate that FUS3/DAC2 may act upstream of CDC28 and provide evidence that the G1 arrest and morphological changes conferred by the cdc37 mutation may require FUS3/DAC2 (MAP kinase), STE7(MEK) and STE11 (MEK kinase).
Laboratory of Genetics and Microbiology, Developmental and Reproductive Biology Center, Yamagata, Japan.
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Fujimura
D000818:Animals; D017489:CDC28 Protein Kinase, S cerevisiae / Q000235:genetics / Q000378:metabolism; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics / Q000502:physiology*; D018797:Cell Cycle Proteins; D002459:Cell Fusion; D016213:Cyclins / Q000235:genetics / Q000502:physiology*; D029721:Drosophila Proteins; D004790:Enzyme Induction; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D007399:Interphase; D048369:MAP Kinase Kinase 1; D020930:MAP Kinase Kinase Kinases / Q000378:metabolism; D008322:Mammals / Q000235:genetics / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D018832:Molecular Chaperones; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012098:Reproduction; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors
C089931:CDC36 protein, S cerevisiae; C513270:CDC37 protein, S cerevisiae; C079592:CDC39 protein, S cerevisiae; C079895:CLN3 protein, S cerevisiae; D018797:Cell Cycle Proteins; D016213:Cyclins; D029721:Drosophila Proteins; D005656:Fungal Proteins; D018832:Molecular Chaperones; D011506:Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; C489241:STE12 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors; C071596:ste11 protein, S pombe; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D017489:CDC28 Protein Kinase, S cerevisiae; C075580:FUS3 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases; D020930:MAP Kinase Kinase Kinases; C067018:Ste11 protein, S cerevisiae; D048369:MAP Kinase Kinase 1; D020929:Mitogen-Activated Protein Kinase Kinases