First Author | Li G | Year | 2009 |
Journal | J Cell Biol | Volume | 186 |
Issue | 6 | Pages | 783-92 |
PubMed ID | 19752026 | Mgi Jnum | J:153833 |
Mgi Id | MGI:4366390 | Doi | 10.1083/jcb.200904060 |
Citation | Li G, et al. (2009) Role of ERO1-alpha-mediated stimulation of inositol 1,4,5-triphosphate receptor activity in endoplasmic reticulum stress-induced apoptosis. J Cell Biol 186(6):783-92 |
abstractText | Endoplasmic reticulum (ER) stress-induced apoptosis is involved in many diseases, but the mechanisms linking ER stress to apoptosis are incompletely understood. Based on roles for C/EPB homologous protein (CHOP) and ER calcium release in apoptosis, we hypothesized that apoptosis involves the activation of inositol 1,4,5-triphosphate (IP3) receptor (IP3R) via CHOP-induced ERO1-alpha (ER oxidase 1 alpha). In ER-stressed cells, ERO1-alpha is induced by CHOP, and small interfering RNA (siRNA) knockdown of ERO1-alpha suppresses apoptosis. IP3-induced calcium release (IICR) is increased during ER stress, and this response is blocked by siRNA-mediated silencing of ERO1-alpha or IP3R1 and by loss-of-function mutations in Ero1a or Chop. Reconstitution of ERO1-alpha in Chop(-/-) macrophages restores ER stress-induced IICR and apoptosis. In vivo, macrophages from wild-type mice but not Chop(-/-) mice have elevated IICR when the animals are challenged with the ER stressor tunicamycin. Macrophages from insulin-resistant ob/ob mice, another model of ER stress, also have elevated IICR. These data shed new light on how the CHOP pathway of apoptosis triggers calcium-dependent apoptosis through an ERO1-alpha-IP3R pathway. |