SMC3/YJL074C Summary Help

Standard Name SMC3
Systematic Name YJL074C
Feature Type ORF, Verified
Description Subunit of the multiprotein cohesin complex; required for sister chromatid cohesion in mitotic cells; also required, with Rec8p, for cohesion and recombination during meiosis; phylogenetically conserved SMC chromosomal ATPase family member (1, 2, 3 and see Summary Paragraph)
Name Description Structural Maintenance of Chromosomes
Chromosomal Location
ChrX:302849 to 299157 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All SMC3 GO evidence and references
  View Computational GO annotations for SMC3
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 5 genes
Classical genetics
reduction of function
Large-scale survey
reduction of function
363 total interaction(s) for 275 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 65
  • Affinity Capture-RNA: 2
  • Affinity Capture-Western: 28
  • Biochemical Activity: 4
  • Co-fractionation: 3
  • Co-localization: 2
  • Co-purification: 3
  • FRET: 3
  • Reconstituted Complex: 6
  • Two-hybrid: 17

Genetic Interactions
  • Dosage Rescue: 1
  • Negative Genetic: 60
  • Phenotypic Enhancement: 3
  • Phenotypic Suppression: 1
  • Positive Genetic: 5
  • Synthetic Growth Defect: 7
  • Synthetic Lethality: 151
  • Synthetic Rescue: 2

Expression Summary
Length (a.a.) 1,230
Molecular Weight (Da) 141,335
Isoelectric Point (pI) 5.62
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrX:302849 to 299157 | 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..3693 302849..299157 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 SGDIDS000003610

SMC3 is an essential gene that encodes a member of a ubiquitous family of chromosome-associated ATPases (1, 4, 5). SMC proteins are found in eukaryotes, prokaryotes, and archaea, and appear to play roles in chromosome dynamics (4, 5). In eukaryotes, SMC proteins form two kinds of heterodimers, corresponding to Smc1p-Smc3p and Smc2p-Smc4p in yeast (4, 5). The Smc1p-Smc3p heterodimer interacts with additional proteins, including Mcd1p and Irr1p, to form the yeast cohesin complex, which is required for sister chromatid cohesion in mitosis and meiosis (6, 7, 2, 4, 5). Smc3p is acetylated by Eco1p during S-phase and remains acetylated through G2/M. This acetylation is required for sister chromatid cohesion (8, 9).

The yeast cohesin complex associates with centromeres and other discrete sites along chromosome arms prior to metaphase; the association with centromeres requires the centromere protein Mif2p, the centromere binding complex CBF3, and Cse4p (10, 11). Scc2p is not a stoichiometric cohesin subunit, but is required for the cohesin complex to associate with chromosomes (7).

Conditional lethal mutations in SMC3 cause premature dissociation of sister chromatids (1). Homozygous smc3-42 diploids fail to sporulate and are defective in synaptonemal complex formation (2).

Cohesin complexes that include homologs of Smc1p and Smc3p have been identified in other eukaryotes, including Xenopus, C. elegans, S. pombe, and human (4). SMC protein homodimers have been found in prokaryotes (5).

Last updated: 2008-08-05 Contact SGD

References cited on this page View Complete Literature Guide for SMC3
1) Michaelis C, et al.  (1997) Cohesins: chromosomal proteins that prevent premature separation of sister chromatids. Cell 91(1):35-45
2) Klein F, et al.  (1999) A central role for cohesins in sister chromatid cohesion, formation of axial elements, and recombination during yeast meiosis. Cell 98(1):91-103
3) Jones S and Sgouros J  (2001) The cohesin complex: sequence homologies, interaction networks and shared motifs. Genome Biol 2(3):RESEARCH0009
4) Hirano T  (1999) SMC-mediated chromosome mechanics: a conserved scheme from bacteria to vertebrates? Genes Dev 13(1):11-9
5) Strunnikov AV and Jessberger R  (1999) Structural maintenance of chromosomes (SMC) proteins: conserved molecular properties for multiple biological functions. Eur J Biochem 263(1):6-13
6) Guacci V, et al.  (1997) A direct link between sister chromatid cohesion and chromosome condensation revealed through the analysis of MCD1 in S. cerevisiae. Cell 91(1):47-57
7) Toth A, et al.  (1999) Yeast cohesin complex requires a conserved protein, Eco1p(Ctf7), to establish cohesion between sister chromatids during DNA replication. Genes Dev 13(3):320-33
8) Ben-Shahar TR, et al.  (2008) Eco1-dependent cohesin acetylation during establishment of sister chromatid cohesion. Science 321(5888):563-6
9) Unal E, et al.  (2008) A molecular determinant for the establishment of sister chromatid cohesion. Science 321(5888):566-9
10) Tanaka T, et al.  (1999) Identification of cohesin association sites at centromeres and along chromosome arms. Cell 98(6):847-58
11) Blat Y and Kleckner N  (1999) Cohesins bind to preferential sites along yeast chromosome III, with differential regulation along arms versus the centric region. Cell 98(2):249-59