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In CK2 inactivated cells the cyclin dependent kinase inhibitor Sic1 is involved in cell-cycle arrest before the onset of S phase.
- Source :
-
Biochemical and biophysical research communications [Biochem Biophys Res Commun] 2007 Aug 10; Vol. 359 (4), pp. 921-7. Date of Electronic Publication: 2007 Jun 04. - Publication Year :
- 2007
-
Abstract
- Protein kinase CK2 is a heterotetramer composed of two catalytic and two regulatory subunits. In Saccharomyces cerevisiae the catalytic subunits (alpha and alpha') are encoded by the CKA1, CKA2 genes. cka1Deltacka2(ts) mutants arrest cell cycle in both G1 and G2/M at 37 degrees C. Hence, it has been proposed that CK2 plays an important role in cell-cycle progression and several cell-cycle proteins have been reported to be CK2 substrates. We have previously shown that Sic1, the inhibitor of Clb5-Cdc28 complexes required for the G1/S transition, is a physiologically relevant CK2 substrate. Here we show that CK2 inactivation up-regulates Sic1 level resulting in severe down-regulation of Clb5-Cdc28 kinase activity. Concurrent inactivation of Sic1 and CK2 leads to accumulation of cells with a post-synthetic DNA content and short/elongated spindles, typical of cells arrested in mitosis. These findings indicate that Sic1 plays a major role during G1 arrest of CK2-inactivated cells.
- Subjects :
- Cyclin-Dependent Kinase Inhibitor Proteins
Gene Expression Regulation, Fungal physiology
Apoptosis physiology
Casein Kinase II metabolism
Cell Cycle Proteins metabolism
S Phase physiology
Saccharomyces cerevisiae cytology
Saccharomyces cerevisiae metabolism
Saccharomyces cerevisiae Proteins metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0006-291X
- Volume :
- 359
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Biochemical and biophysical research communications
- Publication Type :
- Academic Journal
- Accession number :
- 17574209
- Full Text :
- https://doi.org/10.1016/j.bbrc.2007.05.195