Plays a role in the assembly of the HRD1 complex, a complex involved in the ubiquitin-proteasome-dependent process of ER-associated degradation (ERAD). Component of the HRD1 complex, which comprises at least SYNV1/HRD1, FAM8A1, HERPUD1/HERP, OS9, SEL1L and UBE2J1. This interaction stabilizes FAM8A1 protein, preventing its proteasomal degradation. FAM8A1 binding to SYNV1 may promote recruitment of HERPUD1 to the HRD1 complex. Ubiquitously expressed, with a higher level of expression in testis.