| First Author | Kokame K | Year | 2000 |
| Journal | J Biol Chem | Volume | 275 |
| Issue | 42 | Pages | 32846-53 |
| PubMed ID | 10922362 | Mgi Jnum | J:65186 |
| Mgi Id | MGI:1913176 | Doi | 10.1074/jbc.M002063200 |
| Citation | Kokame K, et al. (2000) Herp, a new ubiquitin-like membrane protein induced by endoplasmic reticulum stress. J Biol Chem 275(42):32846-53 |
| abstractText | Hyperhomocysteinemia, a risk factor for vascular disease, injures endothelial cells through undefined mechanisms. We previously identified several homocysteine-responsive genes in cultured human vascular endothelial cells, including the endoplasmic reticulum (ER)-resident molecular chaperone GRP78/BiP. Here, we demonstrate that homocysteine induces the ER stress response and leads to the expression of a novel protein, Herp, containing a ubiquitin-like domain at the N terminus. mRNA expression of Herp was strongly up-regulated by inducers of ER stress, including mercaptoethanol, tunicamycin, A23187, and thapsigargin. The ER stress-dependent induction of Herp was also observed at the protein level. Immunochemical analyses using Herp-specific antibodies indicated that Herp is a 54-kDa, membrane-associated ER protein. Herp is the first integral membrane protein regulated by the ER stress response pathway. Both the N and C termini face the cytoplasmic side of the ER; this membrane topology makes it unlikely that Herp acts as a molecular chaperone for proteins in the ER, in contrast to GRP78 and other ER stress-responsive proteins. Herp may, therefore, play an unknown role in the cellular survival response to stress. |
