ID:SMC1B_HUMAN DESCRIPTION: RecName: Full=Structural maintenance of chromosomes protein 1B; Short=SMC protein 1B; Short=SMC-1-beta; Short=SMC-1B; FUNCTION: Meiosis-specific component of cohesin complex. Required for the maintenance of meiotic cohesion, but not, or only to a minor extent, for its establishment. Contributes to axial element (AE) formation and the organization of chromatin loops along the AE. Plays a key role in synapsis, recombination and chromosome movements. 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 meiosis-specific cohesin complex probably replaces mitosis specific cohesin complex when it dissociates from chromatin during prophase I (By similarity). SUBUNIT: Forms a heterodimer with SMC3. Component of a meiosis- specific cohesin complex, probably composed of the SMC1B and SMC3 heterodimer attached via their hinge domain, RAD21 (or its meiosis-specific related protein REC8), which link them, and STAG3, which interacts with RAD21 or REC8 (By similarity). SUBCELLULAR LOCATION: Nucleus. Chromosome (By similarity). Chromosome, centromere (By similarity). Note=Associates with chromatin. In prophase I stage of meiosis, localizes along the AE of synaptonemal complexes. In late-pachytene-diplotene, the bulk of protein dissociates from the chromosome arms probably because of phosphorylation by PLK, except at centromeres, where cohesin complexes remain. Remains chromatin associated at the centromeres up to metaphase II. At anaphase II, dissociates from centromeres, allowing chromosomes segregation (By similarity). DOMAIN: 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 or REC8 protein, forming a ring structure (By similarity). SIMILARITY: Belongs to the SMC family. SMC1 subfamily. SEQUENCE CAUTION: Sequence=BAC86266.1; Type=Erroneous initiation; Note=Translation N-terminally shortened;
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
Pfam Domains: PF02463 - RecF/RecN/SMC N terminal domain PF06470 - SMC proteins Flexible Hinge Domain PF13175 - AAA ATPase domain PF13304 - AAA domain, putative AbiEii toxin, Type IV TA system
SCOP Domains: 52540 - P-loop containing nucleoside triphosphate hydrolases 53795 - PEP carboxykinase-like 75553 - Smc hinge domain
ModBase Predicted Comparative 3D Structure on Q8NDV3
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
US Server
Sequence and Links to Tools and Databases 
Common Gene Haplotype Alleles 
