title: The Cdc28 inhibitor p40SIC1.
abstract: Sic1 inhibits the activity of Cdc28.Clb5 complexes in late G1, creating a delay between cell cycle commitment and S phase initiation. The ultimate purpose of this delay is unknown but loss of Sic1 activity negatively affects genomic stability and cellular viability. Sic1 levels are controlled by periodic changes in transcription rates and protein stability. The latter control is mediated through the Cdc34 ubiquitin transferase and, possibly, Cdc28.Cln activity. Possible roles of Sic1 in the G1/S and the M/G1 transitions are discussed.
authors.affiliation: Department of Biochemistry, Chandler Medical Center, University of Kentucky, Lexington 40536-0096, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Mendenhall
authors.forename: W
authors.initials: W
authors.lastname: al-Jumaily
authors.forename: T T
authors.initials: TT
authors.lastname: Nugroho
mesh_terms: D017489:CDC28 Protein Kinase, S cerevisiae / Q000037:antagonists & inhibitors*; D050756:Cyclin-Dependent Kinase Inhibitor Proteins; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors; D005656:Fungal Proteins / Q000502:physiology*; D008954:Models, Biological; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins
chemical_list: D050756:Cyclin-Dependent Kinase Inhibitor Proteins; D004791:Enzyme Inhibitors; D005656:Fungal Proteins; C086926:SIC1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D017489:CDC28 Protein Kinase, S cerevisiae; D018844:Cyclin-Dependent Kinases