Glucose-dependent cell size is regulated by a G protein-coupled receptor system in yeast Saccharomyces cerevisiae.
In the yeast, Saccharomyces cerevisiae, cell size is affected by the kind of carbon source in the medium. Here, we present evidence that the Gpr1 receptor and Gpa2 Galpha subunit are required for both maintenance and modulation of cell size in response to glucose. In the presence of glucose, mutants lacking GPR1 or GPA2 gene showed smaller cells than the wild-type strain. Physiological studies revealed that protein synthesis rate was reduced in the mutant strains indicating that reduced growth rate, while the level of mRNAs for CLN1, 2 and 3 was not affected in all strains. Gene chip analysis also revealed a down-regulation in the expression of genes related to biosynthesis of not only protein but also other cellular component in the mutant strains. We also show that GPR1 and GPA2 are required for a rapid increase in cell size in response to glucose. Wild-type cells grown in ethanol quickly increased in size by addition of glucose, while little change was observed in the mutant strains, in which glucose-dependent cell cycle arrest caused by CLN1 repression was somewhat alleviated. Our study indicates that the yeast G-protein coupled receptor system consisting of Gpr1 and Gpa2 regulates cell size by affecting both growth rate and cell division.
Tamaki
Hisanori
H
Division of Integrated Life Sciences, Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan. noritama@kais.kyoto-u.ac.jp
Yun
Cheol-Won
CW
Mizutani
Tomohiro
T
Tsuzuki
Takahiro
T
Takagi
Yukinobu
Y
Shinozaki
Makiko
M
Kodama
Yukiko
Y
Shirahige
Katsuhiko
K
Kumagai
Hidehiko
H
D016213:Cyclins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D016193:G1 Phase / Q000502:physiology; D044385:GTP-Binding Protein alpha Subunits / Q000235:genetics / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D005947:Glucose / Q000502:physiology*; D009154:Mutation; D012333:RNA, Messenger / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
C082719:CLN1 protein, S cerevisiae; C082721:CLN2 protein, S cerevisiae; C079895:CLN3 protein, S cerevisiae; D016213:Cyclins; C109334:GPR1 protein, S cerevisiae; D044385:GTP-Binding Protein alpha Subunits; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; D029701:Saccharomyces cerevisiae Proteins; C083907:Gpa2 protein, S cerevisiae; D005947:Glucose