PIG1/YLR273C Summary Help

Standard Name PIG1 1
Systematic Name YLR273C
Feature Type ORF, Verified
Description Putative targeting subunit for type-1 protein phosphatase Glc7p; tethers Glc7p to Gsy2p glycogen synthase; PIG1 has a paralog, GAC1, that arose from the whole genome duplication (1, 2 and see Summary Paragraph)
Name Description Protein Interacting with Gsy2p 1
Chromosomal Location
ChrXII:691029 to 689083 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All PIG1 GO evidence and references
  View Computational GO annotations for PIG1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 4 genes
Classical genetics
Large-scale survey
25 total interaction(s) for 24 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 2
  • Affinity Capture-RNA: 1
  • PCA: 1
  • Two-hybrid: 3

Genetic Interactions
  • Dosage Growth Defect: 2
  • Negative Genetic: 12
  • Phenotypic Enhancement: 1
  • Positive Genetic: 2
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 648
Molecular Weight (Da) 74,145
Isoelectric Point (pI) 4.96
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXII:691029 to 689083 | 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..1947 691029..689083 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 | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000004263

Pig1p is a putative targeting subunit for the type-1 protein phosphatase Glc7p that tethers it to the Gsy2p glycogen synthase (1, 3). Pig1p binds Gsy2p in two-hybrid analyses, and PIG1 displays overall similarity to GAC1, suggesting that Pig1p may functionally overlap Gac1p, which also tethers Glc7p to Gsy2p, in glycogen biosynthesis (1).

pig1 gac1 double null mutants display decreased glycogen accumulation compared to either gac1 null mutants or wild type (1). glc7-109 mutants display increased levels of glycogen compared to wild type, and this hyperglycogen phenotype is partially retained in pig1 gac1 gip2 triple null glc7-109 mutants, indicating there may be other targeting subunits capable of targeting Glc7p-109 to Gsy2p (3). The growth of pig1 ppz1 ppz2 triple null mutants appears identical to that of ppz1 ppz2 double null mutants, indicating that there are no genetic interactions between PIG1 and PPZ1 and PPZ2, both of which encode Glc7p-related protein phosphatases (4).

Pig1p, Gac1p, Pig2p and Gip2p are the only four proteins in S. cerevisiae that share a conserved segment of 25 residues, designated the GVNK motif, which is conserved in mammalian type-1 phosphatase targeting subunits (1). Pig1p also has regions of similarity to the Rhizopus glucoamylase precursor AMYG, and also 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: 2005-10-20 Contact SGD

References cited on this page View Complete Literature Guide for PIG1
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) 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
3) Williams-Hart T, et al.  (2002) Protein phosphatase type 1 regulates ion homeostasis in Saccharomyces cerevisiae. Genetics 160(4):1423-37
4) Venturi GM, et al.  (2000) Genetic interactions between GLC7, PPZ1 and PPZ2 in saccharomyces cerevisiae. Genetics 155(1):69-83
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