ETEA/UBXD8 (D8H6D) Rabbit mAb #34945

Ubiquitin regulatory X domain-containing protein 8 (UBXD8, also known as ETEA and FAF2) is a hairpin-anchored endoplasmic reticulum (ER) protein involved in ER associated degradation (ERAD). It influences this process by promoting translocation of misfolded proteins from the ER lumen to the cytoplasm for proteasome-mediated degradation (1). UBXD8 is a sensor for unsaturated fatty acids. In the absence of fatty acids UBXD8 binds to and targets INSIG1 for degradation, ultimately resulting in activation of SREBP-1. Under this condition, UBXD8 also inhibits triglyceride synthesis by blocking the conversion of diacylglycerols into triglycerides. Unsaturated fatty acids trigger UBXD8 polymerization and dissociation of UBXD8/INSIG1 complex, leading to feedback inhibition of SREBP-1 (2, 3). This induces UBXD8 to translocate from the ER to lipid droplets, where it binds to ATGL and inhibits its lipase activity (4, 5). The complex containing p97 and UBXD8 is reported to promote disassembly of the ribonucleoprotein complex to control mRNA stability (6). In addition, UBXD8 binds to and promotes degradation of neurofibromin (NF1), suggesting a role in regulating Ras activity (7).