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Mol Gen Genet

Title:		Cyclin-specific START events and the G1-phase specificity of arrest by mating factor in budding yeast
Author(s):		Oehlen LJ; Jeoung DI; Cross FR;
Address:		"The Rockefeller University, New York, NY 10021, USA"
Journal Title:		Mol Gen Genet
Year:		1998
Volume:		258
Issue:		3
Page Number:		183 - 198
DOI:		10.1007/s004380050722
ISSN/ISBN:		0026-8925 (Print) 0026-8925 (Linking)
Abstract:		"The START cell cycle transition in the budding yeast Saccharomyces cerevisiae is catalyzed by the Cdc28 cyclin-dependent kinase associated with Cln-type cyclins. Since ectopic expression of the B-type cyclin CLB5 can efficiently rescue the inviability that results from CLN depletion, we tested the specificity of the CLN and CLB classes of cyclins for promoting START-associated events. Several aspects of the regulation of the mating factor response were compared for cells in which START activity was provided by either Cln-cyclins or Clb5. Unlike Cln1 and Cln2, high level expression of Clb5 was unable to repress the activity of the mating factor response pathway at START. Downregulation of Far1 protein at START is normal in cln- GAL1::CLB5 cells. Even though the Clb5-Cdc28 kinase activity in cln- GAL1::CLB5 cells is not downregulated in response to mating factor, cells arrest in the first cycle after addition of mating factor with a similar sensitivity as wild-type cells. However, whereas wild-type cells treated with mating factor arrest specifically in G1 phase as unbudded cells with unreplicated DNA (pre-START), most cln- GAL1::CLB5 cells arrest as budded post-START cells with replicated DNA. Our findings demonstrate the ability of post-START cells to arrest in response to mating factor and provide novel evidence for mechanisms that contribute to restrict mating factor-induced arrest in wild-type cells to the G1 phase of the cell cycle"
Keywords:		"Cell Cycle/*physiology *Cell Cycle Proteins *Cyclin B Cyclin-Dependent Kinase Inhibitor Proteins Cyclins/physiology Fungal Proteins/physiology G1 Phase/*physiology Gene Expression Regulation, Fungal/genetics Genotype Mating Factor Peptides/*pharmacology P;"
Notes:		"MedlineOehlen, L J Jeoung, D I Cross, F R eng GM49716/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. Germany 1998/06/30 Mol Gen Genet. 1998 May; 258(3):183-98. doi: 10.1007/s004380050722"