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Antonie Van Leeuwenhoek

Title:		The RAS-adenylate cyclase pathway and cell cycle control in Saccharomyces cerevisiae
Author(s):		Thevelein JM;
Address:		"Laboratorium voor Moleculaire Celbiologie, Katholieke Universiteit te Leuven, Heverlee, Flanders, Belgium"
Journal Title:		Antonie Van Leeuwenhoek
Year:		1992
Volume:		62
Issue:		1-Feb
Page Number:		109 - 130
DOI:		10.1007/BF00584466
ISSN/ISBN:		0003-6072 (Print) 0003-6072 (Linking)
Abstract:		"The cell cycle of Saccharomyces cerevisiae contains a decision point in G1 called 'start', which is composed of two specific sites. Nutrient-starved cells arrest at the first site while pheromone-treated cells arrest at the second site. Functioning of the RAS-adenylate cyclase pathway is required for progression over the nutrient-starvation site while overactivation of the pathway renders the cells unable to arrest at this site. However, progression of cycling cells over the nutrient-starvation site does not appear to be triggered by the RAS-adenylate cyclase pathway in response to a specific stimulus, such as an exogenous nutrient. The essential function of the pathway appears to be limited to provision of a basal level of cAMP. cAMP-dependent protein kinase rather than cAMP might be the universal integrator of nutrient availability in yeast. On the other hand stimulation of the pathway in glucose-derepressed yeast cells by rapidly-fermented sugars, such as glucose, is well documented and might play a role in the control of the transition from gluconeogenic growth to fermentative growth. The initial trigger of this signalling pathway is proposed to reside in a 'glucose sensing complex' which has both a function in controlling the influx of glucose into the cell and in activating in addition to the RAS-adenylate cyclase pathway all other glucose-induced regulatory pathways in yeast. Two crucial problems remaining to be solved with respect to cell cycle control are the nature of the connection between the RAS-adenylate cyclase pathway and nitrogen-source induced progression over the nutrient-starvation site of 'start' and second the nature of the downstream processes linking the RAS-adenylate cyclase pathway to Cyclin/CDC28 controlled progression over the pheromone site of 'start'"
Keywords:		"Adenylyl Cyclases/*metabolism Cell Cycle/*physiology Genes, ras/*physiology Oncogene Proteins/metabolism Saccharomyces cerevisiae/*physiology Signal Transduction;"
Notes:		"MedlineThevelein, J M eng Research Support, Non-U.S. Gov't Review Netherlands 1992/08/01 Antonie Van Leeuwenhoek. 1992 Aug; 62(1-2):109-30. doi: 10.1007/BF00584466"