SEC61B

The Sec61 complex is the central component of the protein translocation apparatus of the endoplasmic reticulum (ER) membrane. Oligomers of the Sec61 complex form a transmembrane channel where proteins are translocated across and integrated into the ER membrane. This complex consists of three membrane proteins- alpha, beta, and gamma. This gene encodes the beta-subunit protein. The Sec61 subunits are also observed in the post-ER compartment, suggesting that these proteins can escape the ER and recycle back. There is evidence for multiple polyadenylated sites for this transcript. [provided by RefSeq, Jul 2008]

Full Name

Sec61 Translocon Beta Subunit

Function

Component of SEC61 channel-forming translocon complex that mediates transport of signal peptide-containing precursor polypeptides across the endoplasmic reticulum (ER) (PubMed:12475939).
Component of a ribosome-associated ER translocon complex involved in multi-pass membrane protein transport into the ER membrane and biogenesis (PubMed:32820719).
The SEC61 channel cooperates with the translocating protein TRAM1 to import nascent proteins into the ER (PubMed:19121997).
Required for PKD1/Polycystin-1 biogenesis (By similarity).

Biological Process

Biological Process post-translational protein targeting to membrane, translocationManual Assertion Based On ExperimentIBA:GO_Central
Biological Process retrograde protein transport, ER to cytosolManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process SRP-dependent cotranslational protein targeting to membrane, translocationManual Assertion Based On ExperimentIBA:GO_Central
Biological Process ubiquitin-dependent ERAD pathwayManual Assertion Based On ExperimentIDA:UniProtKB

Cellular Location

Endoplasmic reticulum membrane

Involvement in disease

Loss-of-function SEC61B variations may cause autosomal dominant polycystic liver disease (PCLD) in patients that lack variations in known causative genes, such as PRKCSH and SEC63.

Topology

Cytoplasmic: 2-70
Helical: 71-91