SURF4
Description
The SURF4 (surfeit 4) is a protein-coding gene located on chromosome 9.
SURF4, also known as Surfeit locus protein 4, is a protein involved in regulating the export of certain proteins from the endoplasmic reticulum (ER) to the Golgi apparatus. It specifically transports soluble proteins, including lipoproteins and PCSK9. SURF4 recognizes its cargo proteins through a three-amino-acid sequence near their N-termini. Its yeast counterpart is called Erv29p. The gene's name comes from its location within the surfeit gene cluster, a group of six housekeeping genes lacking sequence similarity. The encoded protein is a conserved integral membrane protein with multiple putative transmembrane regions. In yeast, Surf4's homolog is essential for packaging glycosylated pro-alpha-factor into COPII vesicles. Eliminating Surf4 in the liver decreases plasma lipid levels and prevents atherosclerosis in mice.
SURF4 is a cargo receptor that mediates the export of lipoproteins from the endoplasmic reticulum (ER) to the Golgi apparatus. It binds to lipoproteins containing both APOB and APOA1, playing a role in lipoprotein delivery and lipid homeostasis. SURF4 interacts with the GTPase SAR1B to facilitate lipoprotein transport. It also promotes the secretion of PCSK9 and erythropoietin (EPO). SURF4 may contribute to the maintenance of ER-Golgi intermediate compartment and Golgi architecture.
SURF4 is also known as ERV29.
Associated Diseases
- diabetes mellitus, transient neonatal, 2
- hypoparathyroidism, familial isolated, 2
- permanent neonatal diabetes mellitus 1
