GSY1/YFR015C Summary Help

Standard Name GSY1 1
Systematic Name YFR015C
Feature Type ORF, Verified
Description Glycogen synthase; expression induced by glucose limitation, nitrogen starvation, environmental stress, and entry into stationary phase; GSY1 has a paralog, GSY2, that arose from the whole genome duplication; relocalizes from nucleus to cytoplasmic foci upon DNA replication stress (1, 2, 3, 4, 5, 6, 7 and see Summary Paragraph)
Name Description Glycogen SYnthase 1
Chromosomal Location
ChrVI:176391 to 174265 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All GSY1 GO evidence and references
  View Computational GO annotations for GSY1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Regulators 26 genes
Classical genetics
Large-scale survey
45 total interaction(s) for 32 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 24
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 1
  • Co-purification: 1
  • Two-hybrid: 3

Genetic Interactions
  • Dosage Growth Defect: 1
  • Dosage Lethality: 1
  • Negative Genetic: 2
  • Phenotypic Suppression: 1
  • Positive Genetic: 3
  • Synthetic Growth Defect: 3
  • Synthetic Lethality: 1
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 708
Molecular Weight (Da) 80,510
Isoelectric Point (pI) 5.93
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrVI:176391 to 174265 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..2127 176391..174265 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | E.C. | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000001911

Glycogen, a branched polymer of glucose, is a storage molecule whose accumulation is under rigorous nutritional control in many cells (8). In S. cerevisiae, glycogen biosynthesis involves three processes: nucleation, elongation, and ramification, or branching (9). GLG1 and GLG2 encode self-glucosylating glycogenin glucosyltransferases (EC: involved in glycogen nucleation (8). Both Glg1p and Glg2p are able to use UDP-glucose to produce a short alpha (1,4)-glucosyl chain covalently attached to an internal tyrosine residue (10). Glycogen synthase (EC:, Gsy1p and Gsy2p) is then able to extend the linear alpha (1,4)-chains of glycogen by catalyzing the formation of alpha (1,4)-glucosidic bonds from UDP-glucose at the non-reducing ends (11). Branches can be added into the glycogen molecule by Glc3p, the glycogen branching enzyme (EC: in S. cerevisiae (12). No enzyme that releases the glycogen chain from Glg1p or Glg2p has been identified (9).

GSY1 encodes approximately 10-15% of the glycogen synthase activity in S. cerevisiae (11). Although Gsy1p appears less abundant than Gsy2p, Gsy1p levels may provide important fine tuning of glycogen synthase levels under some conditions, as suggested by the complex nature of its promoter (5). The GSY1 promoter contains multiple stress response elements (STREs), also found in the GSY2 promoter, but also includes multiple negative elements which are not found in the GSY2 promoter, such as a Mig1p binding site, a Rox1p binding site, and a novel negative cis element (5). GSY1 is induced upon glucose limitation, nitrogen limitation, stationary phase, osmotic shock, and heat shock (5). GSY1 has similarity to human glycogen synthase genes GYS1 and GYS2 (13).

Last updated: 2005-08-30 Contact SGD

References cited on this page View Complete Literature Guide for GSY1
1) Farkas I, et al.  (1990) Isolation of the GSY1 gene encoding yeast glycogen synthase and evidence for the existence of a second gene. J Biol Chem 265(34):20879-86
2) Parrou JL, et al.  (1999) Dynamic responses of reserve carbohydrate metabolism under carbon and nitrogen limitations in Saccharomyces cerevisiae. Yeast 15(3):191-203
3) Peng ZY, et al.  (1990) Purification and characterization of glycogen synthase from a glycogen-deficient strain of Saccharomyces cerevisiae. J Biol Chem 265(23):13871-7
4) Ni HT and LaPorte DC  (1995) Response of a yeast glycogen synthase gene to stress. Mol Microbiol 16(6):1197-205
5) Unnikrishnan I, et al.  (2003) Multiple positive and negative elements involved in the regulation of expression of GSY1 in Saccharomyces cerevisiae. J Biol Chem 278(29):26450-7
6) Byrne KP and Wolfe KH  (2005) The Yeast Gene Order Browser: combining curated homology and syntenic context reveals gene fate in polyploid species. Genome Res 15(10):1456-61
7) Tkach JM, et al.  (2012) Dissecting DNA damage response pathways by analysing protein localization and abundance changes during DNA replication stress. Nat Cell Biol 14(9):966-76
8) Cheng C, et al.  (1995) Requirement of the self-glucosylating initiator proteins Glg1p and Glg2p for glycogen accumulation in Saccharomyces cerevisiae. Mol Cell Biol 15(12):6632-40
9) Francois J and Parrou JL  (2001) Reserve carbohydrates metabolism in the yeast Saccharomyces cerevisiae. FEMS Microbiol Rev 25(1):125-45
10) Mu J, et al.  (1996) Initiation of glycogen synthesis in yeast. Requirement of multiple tyrosine residues for function of the self-glucosylating Glg proteins in vivo. J Biol Chem 271(43):26554-60
11) Farkas I, et al.  (1991) Two glycogen synthase isoforms in Saccharomyces cerevisiae are coded by distinct genes that are differentially controlled. J Biol Chem 266(24):15602-7
12) Thon VJ, et al.  (1992) Coordinate regulation of glycogen metabolism in the yeast Saccharomyces cerevisiae. Induction of glycogen branching enzyme. J Biol Chem 267(21):15224-8
13) Hardy TA and Roach PJ  (1993) Control of yeast glycogen synthase-2 by COOH-terminal phosphorylation. J Biol Chem 268(32):23799-805