SHM1/YBR263W Summary Help

Standard Name SHM1 1
Systematic Name YBR263W
Alias SHMT1 , TMP3 2
Feature Type ORF, Verified
Description Mitochondrial serine hydroxymethyltransferase; converts serine to glycine plus 5,10 methylenetetrahydrofolate; involved in generating precursors for purine, pyrimidine, amino acid, and lipid biosynthesis; reverse reaction generates serine (1, 3, 4 and see Summary Paragraph)
Name Description Serine HydroxyMethyltransferase 1, 4
Chromosomal Location
ChrII:736264 to 737736 | ORF Map | GBrowse
Gene Ontology Annotations All SHM1 GO evidence and references
  View Computational GO annotations for SHM1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 8 genes
Classical genetics
reduction of function
Large-scale survey
43 total interaction(s) for 35 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 9
  • Affinity Capture-RNA: 4

Genetic Interactions
  • Negative Genetic: 14
  • Phenotypic Suppression: 1
  • Positive Genetic: 3
  • Synthetic Growth Defect: 3
  • Synthetic Lethality: 8
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 490
Molecular Weight (Da) 53,686
Isoelectric Point (pI) 9.3
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrII:736264 to 737736 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 2003-09-22
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1473 736264..737736 2011-02-03 2003-09-22
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 SGDIDS000000467

SHM1 encodes the mitochondrial isoform of serine hydroxymethyltransferase (SHMT) (5, 2), an enzyme which reversibly converts serine to the products glycine and 5,10 methylene tetrahydrofolate (CH2-THF). CH2-THF serves as a one-carbon donor for reactions leading into purine, pyrimidine, amino acid, and lipid biosynthesis (3). Shm1p activity comprises only about 5% of the total cellular SHMT activity (4, 3), but it does contribute measurably to glycine biosynthesis when serine is available (4); when serine is limited, Shm1p functions in the direction of serine biosynthesis (3). Consistent with the relatively minor role of this isoform, the shm1 null mutation does not confer any nutritional requirements (4); however, an uncharacterized mutant allele of shm1 (designated tmp3) blocks respiratory growth (5). SHM1 transcription is not highly regulated, in contrast to the cytosolic isoform SHM2 whose transcription responds to glycine and one-carbon compound levels (6, 7).

Shm1p and Shm2p have similarity to other SHMTs, which are conserved from bacteria to humans (4, 8). Mutation of an isoform of SHMT in C. elegans has a maternal effect lethal phenotype (8), and the human ortholog of Shm2p, SHMT1 (OMIM) is implicated in Smith-Magenis syndrome.

Last updated: 2008-01-29 Contact SGD

References cited on this page View Complete Literature Guide for SHM1
1) Taylor BV, et al.  (1993) Cloning of the genes encoding the serine hydroxymethyltransferases from Saccharomyces cerevisiae. Adv Exp Med Biol 338:711-4
2) Zelikson R and Luzzati M  (1976) Two forms of serine transhydroxymethylase, one absent in a thymidylate-less mutant in Saccharomyces cerevisiae. Eur J Biochem 64(1):7-13
3) Kastanos EK, et al.  (1997) Role of mitochondrial and cytoplasmic serine hydroxymethyltransferase isozymes in de novo purine synthesis in Saccharomyces cerevisiae. Biochemistry 36(48):14956-64
4) McNeil JB, et al.  (1994) Cloning and molecular characterization of three genes, including two genes encoding serine hydroxymethyltransferases, whose inactivation is required to render yeast auxotrophic for glycine. J Biol Chem 269(12):9155-65
5) Luzzati M  (1975) Isolation and properties of a thymidylate-less mutant in Saccharomyces cerevisiae. Eur J Biochem 56(2):533-8
6) Subramanian M, et al.  (2005) Transcriptional regulation of the one-carbon metabolism regulon in Saccharomyces cerevisiae by Bas1p. Mol Microbiol 57(1):53-69
7) Gelling CL, et al.  (2004) Identification of a novel one-carbon metabolism regulon in Saccharomyces cerevisiae. J Biol Chem 279(8):7072-81
8) Vatcher GP, et al.  (1998) Serine hydroxymethyltransferase is maternally essential in Caenorhabditis elegans. J Biol Chem 273(11):6066-73