The mitotic inducer nim1+ functions in a regulatory network of protein kinase homologs controlling the initiation of mitosis.
The newly discovered fission yeast mitotic control element nim1+ (new inducer of mitosis) is the first dose-dependent mitotic inducer identified as a protein kinase homolog. Increased nim1+ expression rescues mutants lacking the mitotic inducer cdc25+ and advances cells into mitosis at a reduced cell size; loss of nim1+ delays mitosis until cells have grown to a larger size. The nim1+ gene potentially encodes a 50 kd protein that contains the consensus sequences of protein kinases. Genetic evidence indicates that nim1+ is a negative regulator of the wee1+ mitotic inhibitor, another protein kinase homolog. The combined mitotic induction activities of nim1+ and cdc25+ counteract the wee1+ mitotic inhibitor in a regulatory network that appears also to involve the cdc2+ protein kinase, which is required for mitosis.
Russell
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Nurse
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D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D005796:Genes; D005800:Genes, Fungal; D005809:Genes, Regulator; D005838:Genotype; D008938:Mitosis; D009154:Mutation; D011494:Protein Kinases / Q000235:genetics*; D004718:Saccharomycetales / Q000235:genetics*; D012568:Schizosaccharomyces / Q000166:cytology / Q000201:enzymology / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid
D011494:Protein Kinases