Ribophorins 1 and 2 are abundant and highly conserved glycoproteins residing in the endoplasic reticulum, that participate in ribosome binding. Mammalian oligosaccharyltransferase activity is associated with a protein complex composed of RPN1, RPN2, and an oligosaccharyltransferase protein. RPN1 is a component of the proteasome base. The ubiquitin-like (UBL) domain of recombinant Rad23 interacts with proteasomes through the leucine-rich repeat domain of RPN1. The RPN1 gene maps to chromosome 3 in somatic cell hybrids, and the RPN2 gene maps to chromosome 20 by in situ hybridization.

2-8°C (short-term); -20°C (long-term)