GLG2/YJL137C Summary Help

Standard Name GLG2 1
Systematic Name YJL137C
Feature Type ORF, Verified
Description Glycogenin glucosyltransferase; self-glucosylating initiator of glycogen synthesis, also glucosylates n-dodecyl-beta-D-maltoside; similar to mammalian glycogenin; GLG2 has a paralog, GLG1, that arose from the whole genome duplication (1, 2, 3 and see Summary Paragraph)
Name Description Glycogenin-Like Gene 1
Chromosomal Location
ChrX:156127 to 154985 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All GLG2 GO evidence and references
  View Computational GO annotations for GLG2
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Regulators 6 genes
Classical genetics
Large-scale survey
31 total interaction(s) for 23 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 4
  • Affinity Capture-RNA: 1
  • Biochemical Activity: 3
  • Protein-RNA: 1
  • Reconstituted Complex: 1
  • Two-hybrid: 7

Genetic Interactions
  • Negative Genetic: 5
  • Phenotypic Enhancement: 2
  • Phenotypic Suppression: 1
  • Positive Genetic: 6

Expression Summary
Length (a.a.) 380
Molecular Weight (Da) 44,546
Isoelectric Point (pI) 5.96
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrX:156127 to 154985 | 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..1143 156127..154985 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 SGDIDS000003673

Glycogen, a branched polymer of glucose, is a storage molecule whose accumulation is under rigorous nutritional control in many cells (1). In S. cerevisiae, glycogen biosynthesis involves three processes: nucleation, elongation, and ramification, or branching (4). GLG1 and GLG2 encode self-glucosylating glycogenin glucosyltransferases (EC: involved in glycogen nucleation (1). 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 (2). 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 (5). Branches can be added into the glycogen molecule by Glc3p, the glycogen branching enzyme (EC: in S. cerevisiae (6). No enzyme that releases the glycogen chain from Glg1p or Glg2p has been identified (4).

GLG1 mRNA, and presumably GLG2 mRNA, begins to accumulate when approximately 50% of the environmental glucose is gone, and peaks when environmental glucose is exhausted, similar to other glycogen metabolism genes (7). Glg1p and Glg2p both are important for glycogen nucleation, since both glg1 and glg2 null mutants display normal glycogen accumulation, but a glg1 glg2 double null mutant is unable to accumulate glycogen (1). Glg1p and Glg2p may also be involved in regulating the activity of glycogen synthase (Gsy1p and Gsy2p), because a glg1 glg2 double null mutant displays normal levels of Gsy1p and Gsy2p but reduced activity of these proteins (1). GLG1 and GLG2 display sequence similarity to human glycogenin genes GYG and GYG2 (1).

Last updated: 2005-08-30 Contact SGD

References cited on this page View Complete Literature Guide for GLG2
1) 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
2) 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
3) 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
4) Francois J and Parrou JL  (2001) Reserve carbohydrates metabolism in the yeast Saccharomyces cerevisiae. FEMS Microbiol Rev 25(1):125-45
5) 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
6) 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
7) Parrou JL, et al.  (1999) Dynamic responses of reserve carbohydrate metabolism under carbon and nitrogen limitations in Saccharomyces cerevisiae. Yeast 15(3):191-203