کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2201061 | 1099995 | 2011 | 8 صفحه PDF | دانلود رایگان |
Stress in mitochondria or the endoplasmic reticulum (ER) independently causes cell death. Recently, it was reported that ER stress causes mitochondrial dysfunction via p53-upregulated modulator of apoptosis (PUMA). However, little is known regarding the mitochondria molecules that mediate ER dysfunction. The present study revealed that tumor necrosis factor receptor-associated protein 1 (TRAP1), which localizes in the mitochondria, is associated with the unfolded protein response (UPR) in the ER.TRAP1 knockdown activated the ER-resident caspase-4, which is activated by ER stress, to induce cell death in humans. However, TRAP1 knockdown cells did not show a significant increase in the level of cell death at least within 24 h after early phase of ER stress in comparison with that of the control cells. This finding could be attributed to a number of reasons. TRAP1 knockdown failed to activate caspase-9, which is activated by activated caspase-4. In addition, TRAP1 knockdown increased the basal level of GRP78/BiP expression, which protects cells, and decreased the basal level of C/EBP homologous protein (CHOP) expression, which induces cell death, even under ER stress. Thus, the present study revealed that mitochondria could be a potential regulator of the UPR in the ER through mitochondrial TRAP1.
Research highlights
► TRAP1 knockdown activated the ER-resident caspase-4.
► TRAP1 knockdown increased the basal level of GRP78/BiP expression.
► TRAP1 knockdown decreased the basal level of CHOP expression.
► TRAP1 might be involved in the unfolded protein response (UPR) pathways.
Journal: Neurochemistry International - Volume 58, Issue 8, July 2011, Pages 880–887