PIG2/YIL045W Summary Help

Standard Name PIG2 1
Systematic Name YIL045W
Feature Type ORF, Verified
Description Putative type-1 protein phosphatase targeting subunit; tethers Glc7p type-1 protein phosphatase to Gsy2p glycogen synthase; PIG2 has a paralog, GIP2, that arose from the whole genome duplication (1, 2, 3 and see Summary Paragraph)
Name Description Protein Interacting with Gsy2p 1
Chromosomal Location
ChrIX:271161 to 272777 | ORF Map | GBrowse
Gene Ontology Annotations All PIG2 GO evidence and references
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Regulators 6 genes
Classical genetics
Large-scale survey
28 total interaction(s) for 27 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 11
  • Affinity Capture-RNA: 1
  • Two-hybrid: 5

Genetic Interactions
  • Dosage Growth Defect: 1
  • Negative Genetic: 9
  • Phenotypic Enhancement: 1

Expression Summary
Length (a.a.) 538
Molecular Weight (Da) 61,938
Isoelectric Point (pI) 8.95
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrIX:271161 to 272777 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1994-12-10
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1617 271161..272777 2011-02-03 1994-12-10
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000001307

Pig2p is a putative type-1 protein phosphatase (PP1) targeting subunit that tethers the Glc7p type-1 protein phosphatase to the Gsy2p glycogen synthase (2). Pig2p binds Gsy2p in two-hybrid analyses, and displays 30% similarity to Gip2p, another putative regulatory subunit of the protein phosphatase Glc7p (1).

One traditional analysis has shown that a pig2 null mutant in the EG328-1A strain background accumulates normal levels of glycogen (1). However, in a large-scale study using a homozygous diploid deletion series in the BY4743 strain background, a pig2 null mutant accumulates less glycogen than wild type (4). glc7-109 mutants display increased levels of glycogen, and this hyperglycogen phenotype is partially retained in pig1 gac1 gip2 triple null glc7-109 mutants, indicating that Pig2p may be a redundant targeting subunit capable of targeting Glc7p-109 to Gsy2p (2).

Gac1p, Pig1p, Pig2p and Gip2p are the only four yeast proteins that share a conserved segment of 25 residues, designated the GVNK motif, which is also found in mammalian type-1 protein phosphatase targeting subunits (1). Pig2p also possesses two short regions of similarity to the Rhizopus glucoamylase precursor AMYG, and to various mammalian glycogen-associated regulatory subunits of protein phosphatase 1 (1), including rabbit RG RAB and human PPP1R3, mutations in which are associated with non-insulin-dependent diabetes mellitus (5).

Last updated: 2005-10-25 Contact SGD

References cited on this page View Complete Literature Guide for PIG2
1) Cheng C, et al.  (1997) Yeast PIG genes: PIG1 encodes a putative type 1 phosphatase subunit that interacts with the yeast glycogen synthase Gsy2p. Yeast 13(1):1-8
2) Williams-Hart T, et al.  (2002) Protein phosphatase type 1 regulates ion homeostasis in Saccharomyces cerevisiae. Genetics 160(4):1423-37
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) Wilson WA, et al.  (2002) Systematic identification of the genes affecting glycogen storage in the yeast Saccharomyces cerevisiae: implication of the vacuole as a determinant of glycogen level. Mol Cell Proteomics 1(3):232-42
5) Tu J, et al.  (1996) Protein phosphatase type 1 interacts with proteins required for meiosis and other cellular processes in Saccharomyces cerevisiae. Mol Cell Biol 16(8):4199-206