Q9Z1M9 (SMC1A_RAT) Reviewed, UniProtKB/Swiss-Prot
Last modified April 3, 2013. Version 95. History...
Names and origin
|Protein names||Recommended name:|
Structural maintenance of chromosomes protein 1A
Short name=SMC protein 1A
|Organism||Rattus norvegicus (Rat) [Reference proteome]|
|Taxonomic identifier||10116 [NCBI]|
|Taxonomic lineage||Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus|
|Sequence length||1233 AA.|
|Protein existence||Evidence at protein level|
General annotation (Comments)
Involved in chromosome cohesion during cell cycle and in DNA repair. Central component of cohesin complex. The cohesin complex is required for the cohesion of sister chromatids after DNA replication. The cohesin complex apparently forms a large proteinaceous ring within which sister chromatids can be trapped. At anaphase, the complex is cleaved and dissociates from chromatin, allowing sister chromatids to segregate. The cohesin complex may also play a role in spindle pole assembly during mitosis. Involved in DNA repair via its interaction with BRCA1 and its related phosphorylation by ATM, or via its phosphorylation by ATR. Works as a downstream effector both in the ATM/NBS1 branch and in the ATR/MSH2 branch of S-phase checkpoint.
Interacts with POLE. Forms a heterodimer with SMC3 in cohesin complexes. Cohesin complexes are composed of the SMC1 (SMC1A or meiosis-specific SMC1B) and SMC3 heterodimer attached via their hinge domain, RAD21 which link them, and one STAG protein (STAG1, STAG2 or meiosis-specific STAG3), which interacts with RAD21. In germ cell cohesin complexes, SMC1A is mutually exclusive with SMC1B. Interacts with BRCA1. Found in a complex with CDCA5, SMC3 and RAD21, PDS5A/APRIN and PDS5B/SCC-112. Interacts with NDC80 By similarity. Interacts with RPGR By similarity. Interacts with SYCP2. Ref.2
Nucleus By similarity. Chromosome By similarity. Note: Associates with chromatin. Before prophase it is scattered along chromosome arms. During prophase, most of cohesin complexes dissociate from chromatin probably because of phosphorylation by PLK, except at centromeres, where cohesin complexes remain. At anaphase, the RAD21 subunit of the cohesin complex is cleaved, leading to the dissociation of the complex from chromosomes, allowing chromosome separation. In germ cells, cohesin complex dissociates from chromatin at prophase I, and may be replaced by a meiosis-specific cohesin complex. The phosphorylated form on Ser-957 and Ser-966 associates with chromatin during G1/S/G2 phases but not during M phase, suggesting that phosphorylation does not regulate cohesin function By similarity.
The flexible hinge domain, which separates the large intramolecular coiled coil regions, allows the heterotypic interaction with the corresponding domain of SMC3, forming a V-shaped heterodimer. The two heads of the heterodimer are then connected by different ends of the cleavable RAD21 protein, forming a ring structure By similarity.
Phosphorylated upon ionizing radiation or DNA methylation. Phosphorylation of Ser-957 and Ser-966 activates it and is required for S-phase checkpoint activation By similarity.
Sequence annotation (Features)
|Feature key||Position(s)||Length||Description||Graphical view||Feature identifier|
|Chain||1 – 1233||1233||Structural maintenance of chromosomes protein 1A||PRO_0000118991|
|Nucleotide binding||32 – 39||8||ATP Potential|
|Region||504 – 659||156||Flexible hinge|
|Coiled coil||104 – 124||21||Potential|
|Coiled coil||163 – 503||341||Potential|
|Coiled coil||660 – 935||276||Potential|
|Coiled coil||991 – 1068||78||Potential|
|Compositional bias||1128 – 1163||36||Ala/Asp-rich (DA-box)|
Amino acid modifications
|Modified residue||358||1||Phosphoserine By similarity|
|Modified residue||360||1||Phosphoserine By similarity|
|Modified residue||648||1||N6-acetyllysine By similarity|
|Modified residue||713||1||N6-acetyllysine By similarity|
|Modified residue||957||1||Phosphoserine By similarity|
|Modified residue||966||1||Phosphoserine By similarity|
|Modified residue||970||1||Phosphoserine By similarity|
|||"Molecular characterization of a rat heterochromatin-associated SMC-protein."|
Althoff B., Voelkl A., Fahimi D., Baumgart E.
Submitted (APR-1998) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
|||"Association of mammalian SMC1 and SMC3 proteins with meiotic chromosomes and synaptonemal complexes."|
Eijpe M., Heyting C., Gross B., Jessberger R.
J. Cell Sci. 113:673-682(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: INTERACTION WITH SYCP2.
|AJ005113 mRNA. Translation: CAA06377.1.|
|RefSeq||NP_113871.1. NM_031683.1. |
3D structure databases
Protein-protein interaction databases
Protocols and materials databases
Genome annotation databases
|RGD||61991. Smc1a. |
Gene expression databases
Family and domain databases
|InterPro||IPR003395. RecF/RecN/SMC. |
|Pfam||PF06470. SMC_hinge. 1 hit. |
PF02463. SMC_N. 1 hit.
|PIRSF||PIRSF005719. SMC. 1 hit. |
|SMART||SM00968. SMC_hinge. 1 hit. |
|SUPFAM||SSF75553. SMC_hinge. 1 hit. |
|Accession||Primary (citable) accession number: Q9Z1M9|
|Entry status||Reviewed (UniProtKB/Swiss-Prot)|
|Annotation program||Chordata Protein Annotation Program|
Index of protein domains and families