PYC1/YGL062W Summary Help

Standard Name PYC1
Systematic Name YGL062W
Feature Type ORF, Verified
Description Pyruvate carboxylase isoform; cytoplasmic enzyme that converts pyruvate to oxaloacetate; differentially regulated than isoform Pyc2p; mutations in the human homolog are associated with lactic acidosis; PYC1 has a paralog, PYC2, that arose from the whole genome duplication (1, 2, 3, 4 and see Summary Paragraph)
Name Description PYruvate Carboxylase
Chromosomal Location
ChrVII:385196 to 388732 | ORF Map | GBrowse
Gene Ontology Annotations All PYC1 GO evidence and references
  View Computational GO annotations for PYC1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 23 genes
Classical genetics
Large-scale survey
44 total interaction(s) for 33 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 14
  • Affinity Capture-RNA: 1
  • Biochemical Activity: 1
  • Co-purification: 1
  • Protein-peptide: 5
  • Reconstituted Complex: 1
  • Two-hybrid: 1

Genetic Interactions
  • Dosage Rescue: 3
  • Negative Genetic: 10
  • Positive Genetic: 1
  • Synthetic Growth Defect: 3
  • Synthetic Lethality: 3

Expression Summary
Length (a.a.) 1,178
Molecular Weight (Da) 130,098
Isoelectric Point (pI) 6.17
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrVII:385196 to 388732 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..3537 385196..388732 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 SGDIDS000003030

Gluconeogenesis is the process whereby glucose is synthesized from non-carbohydrate precursors, which enables yeast cells to grow on non-sugar carbon sources like ethanol, glycerol, or peptone. The reactions of gluconeogenesis, shown here, mediate conversion of pyruvate to glucose, which is the opposite of glycolysis, the formation of pyruvate from glucose. While these two pathways have several reactions in common, they are not the exact reverse of each other. As the glycolytic enzymes phosphofructokinase (Pfk1p, Pfk2p) and pyruvate kinase (Cdc19p) only function in the forward direction, the gluconeogenesis pathway replaces those steps with the enzymes pyruvate carboxylase (Pyc1p, Pyc2p) and phosphoenolpyruvate carboxykinase (Pck1p)-generating oxaloacetate as an intermediate from pyruvate to phosphoenolpyruvate-and also the enzyme fructose-1,6-bisphosphatase (Fbp1p) (reviewed in 5). Overall, the gluconeogenic reactions convert two molecules of pyruvate to a molecule of glucose, with the expenditure of six high-energy phosphate bonds, four from ATP and two from GTP. Expression of genes encoding several of the gluconeogenic enzymes is subject to glucose repression (6).

PYC1 encodes one of the two yeast pyruvate carboxylase isozymes; the other is encoded by PYC2 (7, 8, 1). Pyruvate carboxylase produces oxaloacetate from pyruvate, a process which in many organisms is mitochondrial, but in yeast is cytosolic (9, 10). No obvious phenotype is observed when either PYC1 or PYC2 is disrupted singly, but when both genes are disrupted cells are unable to grow with glucose as the sole carbon source unless aspartate is added to the medium instead of ammonia (8). PYC1 and PYC2 are differentially regulated, with expression influenced by growth phase and carbon source (2). Expression of PYC1 but not PYC2 is also regulated by the type of nitrogen source independently of the carbon source in the medium (11). The RTG genes may contribute to control of PYC1 expression (12). Mutations in PC, the human pyruvate carboxylase gene (OMIM), are associated with pyruvate carboxylase deficiency and ataxia with lactic acidosis (OMIM) (3).

Last updated: 2005-07-22 Contact SGD

References cited on this page View Complete Literature Guide for PYC1
1) Walker ME, et al.  (1991) Yeast pyruvate carboxylase: identification of two genes encoding isoenzymes. Biochem Biophys Res Commun 176(3):1210-7
2) Brewster NK, et al.  (1994) Regulation of pyruvate carboxylase isozyme (PYC1, PYC2) gene expression in Saccharomyces cerevisiae during fermentative and nonfermentative growth. Arch Biochem Biophys 311(1):62-71
3) Foury F  (1997) Human genetic diseases: a cross-talk between man and yeast. Gene 195(1):1-10
4) 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
5) Klein CJ, et al.  (1998) Glucose control in Saccharomyces cerevisiae: the role of Mig1 in metabolic functions. Microbiology 144 ( Pt 1)():13-24
6) Haarasilta S and Oura E  (1975) On the activity and regulation of anaplerotic and gluconeogenetic enzymes during the growth process of baker's yeast. The biphasic growth. Eur J Biochem 52(1):1-7
7) Morris CP, et al.  (1987) Yeast pyruvate carboxylase: gene isolation. Biochem Biophys Res Commun 145(1):390-6
8) Stucka R, et al.  (1991) DNA sequences in chromosomes II and VII code for pyruvate carboxylase isoenzymes in Saccharomyces cerevisiae: analysis of pyruvate carboxylase-deficient strains. Mol Gen Genet 229(2):307-15
9) Pronk JT, et al.  (1996) Pyruvate metabolism in Saccharomyces cerevisiae. Yeast 12(16):1607-33
10) Haarasilta S and Taskinen L  (1977) Location of three key enzymes of gluconeogenesis in baker's yeast. Arch Microbiol 113(1-2):159-61
11) Huet C, et al.  (2000) Regulation of pyc1 encoding pyruvate carboxylase isozyme I by nitrogen sources in Saccharomyces cerevisiae. Eur J Biochem 267(23):6817-23
12) Menendez J and Gancedo C  (1998) Regulatory regions in the promoters of the Saccharomyces cerevisiae PYC1 and PYC2 genes encoding isoenzymes of pyruvate carboxylase. FEMS Microbiol Lett 164(2):345-52