SEC61A1
Description
The SEC61A1 (SEC61 translocon subunit alpha 1) is a protein-coding gene located on chromosome 3.
SEC61A1 encodes a protein belonging to the SecY/Sec61α family that plays a crucial role in the insertion of secretory and membrane polypeptides into the endoplasmic reticulum (ER). It is found associated with membrane-bound ribosomes, either directly or via adaptor proteins. SEC61A1 is the alpha subunit of the heteromeric SEC61 complex, which also includes beta and gamma subunits.
SEC61A1 is a component of the SEC61 channel-forming translocon complex, which mediates the transport of signal peptide-containing precursor polypeptides across the endoplasmic reticulum (ER). It forms a ribosome receptor and a gated pore in the ER membrane, both essential for the cotranslational translocation of nascent polypeptides. SEC61A1 may cooperate with auxiliary proteins SEC62, SEC63, and HSPA5/BiP to facilitate the post-translational transport of small presecretory proteins. The SEC61 channel is also involved in ER membrane insertion of transmembrane proteins. It mediates the insertion of the first few transmembrane segments of proteins, while the insertion of subsequent transmembrane regions of multi-pass membrane proteins is mediated by the multi-pass translocon (MPT) complex. The SEC61 channel collaborates with the translocating protein TRAM1 to import nascent proteins into the ER. SEC61A1 controls the passive efflux of calcium ions from the ER lumen to the cytosol through the SEC61 channel, contributing to the maintenance of cellular calcium homeostasis. It plays a critical role in nephrogenesis, specifically at the pronephros stage.
SEC61A1 is also known as ADTKD5, CVID15, HNFJ4, HSEC61, SEC61, SEC61A.
Associated Diseases
- Tubulointerstitial kidney disease, autosomal dominant, 5
- Immunodeficiency, common variable, 15
- Neutropenia, severe congenital, 11, autosomal dominant
