REG1/YDR028C Summary Help

Standard Name REG1 1
Systematic Name YDR028C
Alias HEX2 2 , 3 , PZF240 4 , SPP43 5 , SRN1 6 , 7 , 8
Feature Type ORF, Verified
Description Regulatory subunit of type 1 protein phosphatase Glc7p; involved in negative regulation of glucose-repressible genes; involved in regulation of the nucleocytoplasmic shuttling of Hxk2p; REG1 has a paralog, REG2, that arose from the whole genome duplication (9, 10, 11, 12, 13 and see Summary Paragraph)
Name Description REsistance to Glucose repression 1
Chromosomal Location
ChrIV:500879 to 497835 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Genetic position: 2.79 cM
Gene Ontology Annotations All REG1 GO evidence and references
  View Computational GO annotations for REG1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 4 genes
Classical genetics
Large-scale survey
194 total interaction(s) for 119 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 53
  • Affinity Capture-RNA: 4
  • Affinity Capture-Western: 18
  • Biochemical Activity: 2
  • PCA: 2
  • Reconstituted Complex: 1
  • Two-hybrid: 13

Genetic Interactions
  • Dosage Growth Defect: 1
  • Dosage Lethality: 1
  • Dosage Rescue: 6
  • Negative Genetic: 10
  • Phenotypic Enhancement: 4
  • Phenotypic Suppression: 10
  • Positive Genetic: 35
  • Synthetic Growth Defect: 3
  • Synthetic Lethality: 8
  • Synthetic Rescue: 23

Expression Summary
Length (a.a.) 1,014
Molecular Weight (Da) 112,615
Isoelectric Point (pI) 4.76
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrIV:500879 to 497835 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Genetic position: 2.79 cM
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..3045 500879..497835 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 SGDIDS000002435

Reg1p is a regulatory subunit for the Glc7p type-1 protein phosphatase (14). Reg1p interacts strongly with Glc7p and directs it to a number of substrates involved in various processes including glucose repression, cell growth, and glycogen accumulation (15). Reg1p interacts with the kinase domain of activated Snf1p and directs Glc7p to the kinase activation loop of Snf1p, resulting in the dephosphorylation and inactivation of Snf1p, and in the glucose-repression of many genes (16). The Reg1p-Glc7p interaction is also important for the transport of the Fbp1p fructose-1,6-bisphosphatase from intermediate vacuole import and degradation (Vid) vesicles to vacuoles during the glucose-induced degradation of Fbp1p, indicating that Reg1p-Glc7p plays an essential role in the trafficking of Vid vesicles to the vacuole (15). The Reg1p-Glc7p interaction also is involved in the proteolysis of maltose permease (Mal11p, Mal21p, Mal31p, Mal41p and Mal61p), and in a very rapid loss of maltose transport activity that cannot be explained by loss of the maltose permease protein alone (14). Reg1p also interacts with 14-3-3 proteins Bmh1p or Bmh2p to effect glucose repression (16). This may occur through facilitation of an interaction between Bmh1p/Bmh2p and the Grr1p component of the SCF-Grr1p ubiquitin ligase complex, which assists Grr1p in recognizing its corresponding phosphorylated substrates and in regulating the induction of HXT1 by glucose (17).

Reg1p expression, localization, and interaction with Glc7p do not appear to be regulated by carbon source, but the activity of the Reg1p-Glc7p complex might be regulated by post-translational phosphorylation of Reg1p, since Reg1p is phosphorylated in a carbon source- and Snf1p-dependent manner (16). reg1 null mutants display slow growth, defects in glycogen accumulation and glucose repression (11), and also possess highly active hyperphosphorylated Snf1p that is constitutively bound to Snf4p (18). reg1 null mutants also undergo slower-than-normal depolarization of the actin cytoskeleton after glucose removal (19). reg1 reg2 double null mutants display a severe growth defect that is alleviated by a loss-of-function mutations in the SNF1-encoded protein kinase (11). Overexpression of REG1 partially restores the defect in the proteolysis of maltose permease seen in grr1 null mutants, but it does not rescue the defects in the rapid inactivation of maltose transport or sensitivity to glucose repression (14).

Last updated: 2005-10-03 Contact SGD

References cited on this page View Complete Literature Guide for REG1
1) Matsumoto K, et al.  (1983) Recessive mutations conferring resistance to carbon catabolite repression of galactokinase synthesis in Saccharomyces cerevisiae. J Bacteriol 153(3):1405-14
2) Entian KD  (1980) A defect in carbon catabolite repression associated with uncontrollable and excessive maltose uptake. Mol Gen Genet 179(1):169-75
3) Entian KD and Zimmermann FK  (1980) Glycolytic enzymes and intermediates in carbon catabolite repression mutants of Saccharomyces cerevisiae. Mol Gen Genet 177(2):345-50
4) Eide LG, et al.  (1996) Sequencing and analysis of a 35.4 kb region on the right [corrected] arm of chromosome IV from Saccharomyces cerevisiae reveal 23 open reading frames. Yeast 12(10B Suppl):1085-90
5) Maddock JR, et al.  (1994) Extragenic suppressors of Saccharomyces cerevisiae prp4 mutations identify a negative regulator of PRP genes. Genetics 136(3):833-47
6) Tung KS, et al.  (1992) SRN1, a yeast gene involved in RNA processing, is identical to HEX2/REG1, a negative regulator in glucose repression. Mol Cell Biol 12(6):2673-80
7) Kraig E, et al.  (1982) Sporulation and rna2 lower ribosomal protein mRNA levels by different mechanisms in Saccharomyces cerevisiae. Mol Cell Biol 2(10):1199-204
8) Pearson NJ, et al.  (1982) A suppressor of temperature-sensitive rna mutations that affect mRNA metabolism in Saccharomyces cerevisiae. Mol Cell Biol 2(5):571-77
9) Niederacher D and Entian KD  (1987) Isolation and characterization of the regulatory HEX2 gene necessary for glucose repression in yeast. Mol Gen Genet 206(3):505-9
10) Tu J and Carlson M  (1995) REG1 binds to protein phosphatase type 1 and regulates glucose repression in Saccharomyces cerevisiae. EMBO J 14(23):5939-46
11) Frederick DL and Tatchell K  (1996) The REG2 gene of Saccharomyces cerevisiae encodes a type 1 protein phosphatase-binding protein that functions with Reg1p and the Snf1 protein kinase to regulate growth. Mol Cell Biol 16(6):2922-31
12) 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
13) Fernandez-Garcia P, et al.  (2012) Phosphorylation of yeast hexokinase 2 regulates its nucleocytoplasmic shuttling. J Biol Chem 287(50):42151-64
14) Jiang H, et al.  (2000) Protein phosphatase type-1 regulatory subunits Reg1p and Reg2p act as signal transducers in the glucose-induced inactivation of maltose permease in Saccharomyces cerevisiae. Mol Gen Genet 263(3):411-22
15) Cui DY, et al.  (2004) The type 1 phosphatase Reg1p-Glc7p is required for the glucose-induced degradation of fructose-1,6-bisphosphatase in the vacuole. J Biol Chem 279(11):9713-24
16) Dombek KM, et al.  (2004) The Reg1-interacting proteins, Bmh1, Bmh2, Ssb1, and Ssb2, have roles in maintaining glucose repression in Saccharomyces cerevisiae. J Biol Chem 279(37):39165-74
17) Tomas-Cobos L, et al.  (2005) TOR kinase pathway and 14-3-3 proteins regulate glucose-induced expression of HXT1, a yeast low-affinity glucose transporter. Yeast 22(6):471-9
18) Hess D and Winston F  (2005) Evidence that Spt10 and Spt21 of Saccharomyces cerevisiae play distinct roles in vivo and functionally interact with MCB-binding factor, SCB-binding factor and Snf1. Genetics 170(1):87-94
19) Uesono Y, et al.  (2004) Simultaneous yet independent regulation of actin cytoskeletal organization and translation initiation by glucose in Saccharomyces cerevisiae. Mol Biol Cell 15(4):1544-56