Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.22 (cdc2)
 8,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The yeast transcription factor Ace2p regulates expression of the chitinase gene CTS1 in a cell cycle-dependent manner. Nuclear localisation of Ace2p is restricted to late M and early G phases of the mitotic cell cycle. We show here that this nuclear localisation is directly associated with regulation of CTS1 expression. Using a version of Ace2p tagged with a c-myc epitope, we show that the protein is excluded from the nucleus of cells during most phases of the mitotic cell cycle. A mutant derivative in which one threonine and two serine residues, which are candidate phosphorylation sites, were replaced by alanine (to mimic constitutive dephosphorylation) is localised in the nucleus throughout the cell cycle. The mechanism of localisation of Ace2p therefore involves regulation of its phosphorylation state, and closely resembles that used by the homologous transcription factor Swi5p. The wild-type Ace2 protein associates with Cdc28p in vivo, suggesting this may be the kinase that mediates the phosphorylation event. The stability of the protein is greatly reduced in a mutant that is constitutively localised to the nucleus, but is restored in a deletion derivative which remains in the cytoplasm. Ace2p is therefore controlled throughout the cell cycle at three levels: transcription, nuclear localisation, and proteolysis.
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PMID:Regulated nuclear localisation of the yeast transcription factor Ace2p controls expression of chitinase (CTS1) in Saccharomyces cerevisiae. 1051 23

SWM1 was originally identified for its role in the late steps of the sporulation process, being required for spore wall assembly. This protein, recently identified as one of the core subunits of the anaphase-promoting complex (APC) is also required to complete cell separation in vegetative cells during growth at high temperature. Mutants lacking SWM1 show a thermosensitive growth defect that is suppressed by osmotic support in the culture medium. At the restrictive temperature, swm1 mutants are unable to complete separation, forming chains of cells that remain associated and, with prolonged incubation times, the stability of the cell wall is compromised, resulting in cell lysis. This separation defect is due to a reduction in expression of CTS1 (the gene encoding chitinase) and a group of genes involved in cell separation (such as ENG1,SCW11, DSE1 and DSE2). Interestingly, these genes are specifically regulated by the transcription factor Ace2p, suggesting that Swm1p is required for normal expression of Ace2p-dependent genes during growth at high temperatures. Although no defect in Ace2p localization can be observed at 28 degrees C, this transcription factor is unable to enter the nucleus of the daughter cell during growth at 38 degrees C. Under these growth conditions, swm1 cells undergo a delay in exit from mitosis, as determined by analysis of Clb2p degradation and Cdc28p-Clb2p kinase assays, and this could be the reason for the cytoplasmic localization of Ace2p.
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PMID:Swm1p subunit of the APC/cyclosome is required for activation of the daughter-specific gene expression program mediated by Ace2p during growth at high temperature in Saccharomyces cerevisiae. 1470 18