- Yeast counterparts of subunits S5a and p58 (S3) of the human 26S proteasome are encoded by two multicopy suppressors of nin1-1. Kominami, K., Okura, N., Kawamura, M., DeMartino, G.N., Slaughter, C.A., Shimbara, N., Chung, C.H., Fujimuro, M., Yokosawa, H., Shimizu, Y., Tanahashi, N., Tanaka, K., Toh-e, A. Mol. Biol. Cell (1997)