SURF4

This gene is located in the surfeit gene cluster, which is comprised of very tightly linked housekeeping genes that do not share sequence similarity. The encoded protein is a conserved integral membrane protein that interacts with endoplasmic reticulum-Golgi intermediate compartment proteins. Disruption of this gene results in reduced numbers of endoplasmic reticulum-Golgi intermediate compartment clusters and redistribution of coat protein I to the cytosol. Alternate splicing results in multiple transcript variants.

Full Name

Surfeit 4

Function

Endoplasmic reticulum cargo receptor that mediates the export of lipoproteins by recruiting cargos into COPII vesicles to facilitate their secretion (PubMed:30251625, PubMed:29643117, PubMed:33186557).
Acts as a cargo receptor for lipoproteins bearing both APOB and APOA1, thereby regulating lipoprotein delivery and the maintenance of lipid homeostasis (PubMed:29643117, PubMed:33186557).
Synergizes with the GTPase SAR1B to mediate transport of circulating lipoproteins (PubMed:33186557).
Promotes the secretion of PCSK9 (PubMed:30251625).
Also mediates the efficient secretion of erythropoietin (EPO) (PubMed:32989016).
May also play a role in the maintenance of the architecture of the endoplasmic reticulum-Golgi intermediate compartment and of the Golgi (PubMed:18287528).

Biological Process

Biological Process Golgi organizationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process lipid homeostasisManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process lipoprotein transportManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process positive regulation of organelle organizationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process regulation of lipid transportManual Assertion Based On ExperimentIDA:UniProtKB

Cellular Location

Endoplasmic reticulum membrane
Endoplasmic reticulum-Golgi intermediate compartment membrane
Golgi apparatus membrane
Cycles between the endoplasmic reticulum and the Golgi.