SOR2/YDL246C Summary Help

Standard Name SOR2 1
Systematic Name YDL246C
Feature Type ORF, Uncharacterized
Description Protein of unknown function; protein sequence is 99% identical to the Sor1p sorbitol dehydrogenase; computational analysis of large-scale protein-protein interaction data also suggests a role in fructose or mannose metabolism (1, 2 and see Summary Paragraph)
Chromosomal Location
ChrIV:9756 to 8683 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All SOR2 GO evidence and references
  View Computational GO annotations for SOR2
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Classical genetics
Large-scale survey
46 total interaction(s) for 45 unique genes/features.
Physical Interactions
  • PCA: 1
  • Two-hybrid: 6

Genetic Interactions
  • Negative Genetic: 35
  • Phenotypic Enhancement: 2
  • Positive Genetic: 2

Expression Summary
Length (a.a.) 357
Molecular Weight (Da) 38,096
Isoelectric Point (pI) 6.71
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrIV:9756 to 8683 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 1996-07-31 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1074 9756..8683 1996-07-31 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 SGDIDS000002405

About SOR1 and SOR2

SOR1 encodes a NAD-dependent sorbitol dehydrogenase that is part of the polyol dehydrogenase branch of the medium-chain dehydrogenase/reductase (MDR) superfamily of enzymes. It is not expressed under most laboratory conditions but is induced when cells are grown in media containing sorbitol, a hexose carbohydrate similar to fructose (3). It is also induced when cells are grown on xylose, a pentose sugar found in lignocellulose, though S. cerevisiae cannot effectively utilize xylose as a carbon source (4). In vitro, Sor1p has been demonstrated to have activity on sorbitol and xylitol, but not on mannitol or the primary alcohol ethanol (3).

SOR2 encodes an enzyme almost identical to SOR1 (2). It has also been predicted to be involved in metabolism of hexoses by computational analysis of protein interaction networks (1).

About the medium-chain dehydrogenase/reductase (MDR) family

Medium-chain dehydrogenase/reductases (MDRs), sometimes referred to as long-chain dehydrogenases (5), constitute an ancient and widespread enzyme superfamily with members found in Bacteria, Archaea, and Eukaryota (6, 7). Many MDR members are basic metabolic enzymes acting on alcohols or aldehydes, and thus these enzymes may have roles in detoxifying alcohols and related compounds, protecting against environmental stresses such as osmotic shock, reduced or elevated temperatures, or oxidative stress (6). The family also includes the mammalian zeta-crystallin lens protein, which may protect the lens against oxidative damage and enzymes which produce lignocellulose in plants (6).

MDR enzymes typically have subunits of about 350 aa residues and are two-domain proteins, with a catalytic domain and a second domain for binding to the nicotinamide cofactor, either NAD(H) or NADP(H) (6, 7). They contain 0, 1, or 2 zinc atoms (8). When zinc is present, it is involved in catalysis at the active site.

Based on phylogenetic and sequence analysis, the members of the MDR superfamily can be further divided into more closely related subgroups (6, 7). In families which are widespread from prokaryotes to eukaryotes, some members appear conserved across all species, while others appear to be due to lineage specific duplications. Some subgroups are only found in certain taxa. S. cerevisiae contains fifteen (6) or twenty-one (7) members of the MDR superfamily, listed below. The difference in number is due to six sequences that were included as members of the quinone oxidoreductase family by Riveros-Rosas et al. (7) but not by Nordling et al. (6).

Zinc-containing enzyme groups:
- PDH; "polyol" dehydrogenase family - BDH1, BDH2, SOR1, SOR2, XYL2
- ADH; class III alcohol dehydrogenase family - SFA1
- Y-ADH; "yeast" alcohol dehydrogenase family - ADH1, ADH2, ADH3, ADH5
- CADH; cinnamyl alcohol dehydrogenase family - ADH6, ADH7

Non-zinc-containing enzyme groups:
- NRBP; nuclear receptor binding protein (7) or MRF; mitochondrial respiratory function (6) family - ETR1
- QOR; quinone oxidoreductase family - ZTA1 (6, 7), AST1, AST2, YCR102C, YLR460C, YMR152W, YNL134C (7)
- LTD; leukotriene B4 dehydrogenases - YML131W
- ER; enoyl reductases (7) or ACR; acyl-CoA reductase (6) family - no members in S. cerevisiae

Last updated: 2008-08-19 Contact SGD

References cited on this page View Complete Literature Guide for SOR2
1) Samanta MP and Liang S  (2003) Predicting protein functions from redundancies in large-scale protein interaction networks. Proc Natl Acad Sci U S A 100(22):12579-83
2) Gonzalez E, et al.  (2000) Characterization of a (2R,3R)-2,3-butanediol dehydrogenase as the Saccharomyces cerevisiae YAL060W gene product. Disruption and induction of the gene. J Biol Chem 275(46):35876-85
3) Sarthy AV, et al.  (1994) Cloning and sequence determination of the gene encoding sorbitol dehydrogenase from Saccharomyces cerevisiae. Gene 140(1):121-6
4) Toivari MH, et al.  (2004) Endogenous xylose pathway in Saccharomyces cerevisiae. Appl Environ Microbiol 70(6):3681-6
5) Jornvall H, et al.  (1981) Alcohol and polyol dehydrogenases are both divided into two protein types, and structural properties cross-relate the different enzyme activities within each type. Proc Natl Acad Sci U S A 78(7):4226-30
6) Nordling E, et al.  (2002) Medium-chain dehydrogenases/reductases (MDR). Family characterizations including genome comparisons and active site modeling. Eur J Biochem 269(17):4267-76
7) Riveros-Rosas H, et al.  (2003) Diversity, taxonomy and evolution of medium-chain dehydrogenase/reductase superfamily. Eur J Biochem 270(16):3309-34
8) Persson B, et al.  (1999) Bioinformatics in studies of SDR and MDR enzymes. Adv Exp Med Biol 463():373-7