Glucose (carbon catabolite) repression is a global regulatory system that governs the expression of many genes in prokaryotes and eukaryotes. Our goal is to understand at the molecular level the mechanisms controlling the global response to glucose availability. We have chosen to study Saccharomyces cerevisiae (yeast) because of the powerful genetics of this small eukaryote. In previous work we have identified regulatory genes essential for control of the SUC2 (invertase) gene and other glucose-repressible genes. We have previously shown that the SNF1 gene encodes a protein kinase essential for release from glucose repression. To obtain insight into the function and regulation of this protein kinase, the SNF1 gene will be subjected to in vitro mutagenesis. Biochemical studies of the SNF1 protein kinase are proposed to examine its activity, phosphorylation, and regulation. To identify genes that are functionally related to SNF1, including those that encode regulators and targets of the protein kinase, extragenic suppressors of SNF1 mutations will be isolated; special effort will be directed towards recovery of allele-specific suppressors to identify genes with products that interact physically with the SNF1 protein kinase. The SNF4 and SSN6 gene products are candidates for a regulator or target of the SNF1 protein kinase. Specific antisera will be raised and these gene products will be characterized. Molecular analysis of two other regulatory genes, SSN1 and CID1, is proposed. Genetic studies to identify new genes required for SUC2 expression are planned, as our evidence suggests that additional genes remain to be identified. Finally, in vitro mutagenesis will be used to identify negative regulatory sites in the SUC2 upstream region, and gel retardation assays will be used to examine interactions of SUC2 sequences with regulatory proteins.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM034095-07
Application #
3284578
Study Section
Genetics Study Section (GEN)
Project Start
1984-07-01
Project End
1992-06-30
Budget Start
1990-07-01
Budget End
1991-06-30
Support Year
7
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Columbia University (N.Y.)
Department
Type
Schools of Medicine
DUNS #
064931884
City
New York
State
NY
Country
United States
Zip Code
10027
Ruiz, Amparo; Xu, Xinjing; Carlson, Marian (2013) Ptc1 protein phosphatase 2C contributes to glucose regulation of SNF1/AMP-activated protein kinase (AMPK) in Saccharomyces cerevisiae. J Biol Chem 288:31052-8
Ruiz, Amparo; Liu, Yang; Xu, Xinjing et al. (2012) Heterotrimer-independent regulation of activation-loop phosphorylation of Snf1 protein kinase involves two protein phosphatases. Proc Natl Acad Sci U S A 109:8652-7
Momcilovic, Milica; Carlson, Marian (2011) Alterations at dispersed sites cause phosphorylation and activation of SNF1 protein kinase during growth on high glucose. J Biol Chem 286:23544-51
Ruiz, Amparo; Xu, Xinjing; Carlson, Marian (2011) Roles of two protein phosphatases, Reg1-Glc7 and Sit4, and glycogen synthesis in regulation of SNF1 protein kinase. Proc Natl Acad Sci U S A 108:6349-54
Liu, Yang; Xu, Xinjing; Carlson, Marian (2011) Interaction of SNF1 protein kinase with its activating kinase Sak1. Eukaryot Cell 10:313-9
Amodeo, Gabriele A; Momcilovic, Milica; Carlson, Marian et al. (2010) Biochemical and functional studies on the regulation of the Saccharomyces cerevisiae AMPK homolog SNF1. Biochem Biophys Res Commun 397:197-201
Momcilovic, Milica; Iram, Surtaj H; Liu, Yang et al. (2008) Roles of the glycogen-binding domain and Snf4 in glucose inhibition of SNF1 protein kinase. J Biol Chem 283:19521-9
Hedbacker, Kristina; Carlson, Marian (2008) SNF1/AMPK pathways in yeast. Front Biosci 13:2408-20
Rudolph, Michael J; Amodeo, Gabriele A; Iram, Surtaj H et al. (2007) Structure of the Bateman2 domain of yeast Snf4: dimeric association and relevance for AMP binding. Structure 15:65-74
Hong, Seung-Pyo; Carlson, Marian (2007) Regulation of snf1 protein kinase in response to environmental stress. J Biol Chem 282:16838-45

Showing the most recent 10 out of 90 publications