Site-directed mutagenesis of the Saccharomyces cerevisiae CDC25 gene: effects on mitotic growth and cAMP signalling.
A potential membrane-interacting site within the essential growth-controlling carboxy-terminal region of the CDC25 protein was interrupted by a lethal mutation (1461 Tyr----Asp and 1462 Leu----Arg). The elimination of two potential phosphorylation sites found in the same region (1489 Thr----Pro and 1584 Ser----Pro) does not affect growth but completely prevents glucose-induced cAMP signalling in the double mutant, whereas the single mutants produce normal or slightly retarded cAMP signals. A cluster of five potential targets for cAMP-dependent phosphorylation at the amino-terminal region could be deleted without affecting phenotypic properties. It is concluded that the carboxy-terminal 137 residues of the CDC25 protein are involved in three different functions: control of mitotic growth, glucose-induced hyperactivation of adenylate cyclase, and feed-back inhibition of cAMP synthesis.
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Max-Planck-Institut für experimentelle Medizin, Abteilung Chemie, Göttingen, Federal Republic of Germany.
Munder
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Küntzel
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D000595:Amino Acid Sequence; D001483:Base Sequence; D018797:Cell Cycle Proteins; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005800:Genes, Fungal; D008938:Mitosis; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010766:Phosphorylation; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D015398:Signal Transduction / Q000235:genetics*; D020666:ras-GRF1
D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D020666:ras-GRF1; D000242:Cyclic AMP