APC/C^Cdh1 is activated under ER stress conditions.

<p>(A) <i>Left</i>, HeLa cells were treated with DMSO or 2.5 µg/ml of tunicamycin (TM) for 8 h. Total cell lysates were immunoblotted for the indicated endogenous proteins. GRP78 served as a marker of ER stress. <i>Right</i>, HeLa cells were harvested at the indicated times after addition of DMSO or 2.5 µg/ml of TM. Total cell lysates were immunoblotted for the indicated endogenous proteins. HSP90 was used as a loading control. (B) HeLa cells were treated with DMSO or 1 µg/ml of tunicamycin for the indicated times. <i>Immunoblots</i>, total cell lysates were immunoblotted for the indicated endogenous proteins. <i>Graphs</i>, transcript levels as measured by SYBR-green qRT-PCR and protein levels as quantified by LiCOR-Odyssey software on immunoblots are compared for the indicated proteins. All measurements were normalized to the DMSO-0 h sample with relative value of 1. (C) HeLa cells were transfected with pSUPER (empty vector) or pSUPER-Cdh1-shRNA (Cdh1-KD). 24 h after transfection, cells were treated with DMSO, 1 µg/ml of TM alone, or 1 µg/ml of TM plus MG-132 (2 or 5 µM) for 16 h. Total cell extracts were immunoblotted for the indicated endogenous proteins.