RNA interference directed against three transducers of the UPR.
A, HREC were transfected with siRNAs targeting IRE1α or control, non-targeted (scramble) siRNAs. Twenty-four hours post-transfection, the culture medium was replaced with glucose-free medium or with standard medium. IRE1α transcript (left) and protein (right) levels were measured after an additional 24 h and compared with levels after 24 h of culture with standard conditions. *, p < 0.05. B, HREC were transfected with siRNAs targeting PERK or control, non-targeted (scramble) siRNAs. Twenty-four hours post-transfection, the culture medium was replaced with glucose-free medium or with standard medium. PERK transcript (left) and protein (right) levels were measured after an additional 24 h and compared with levels after 24 h of culture with standard conditions. *, p < 0.05. C, HREC were transfected with siRNAs targeting ATF6 or control, non-targeted (scramble) siRNAs. Twenty-four hours post-transfection, the culture medium was replaced with glucose-free medium or with standard medium. ATF6 transcript (left) and protein (right) levels were measured after an additional 24 h and compared with levels after 24 h of culture with standard conditions. *, p < 0.05.