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ER stress does not cause upregulation and activation of caspase-2 to initiate apoptosis.

ABSTRACT: A recent report claimed that endoplasmic reticulum (ER) stress activates the ER trans-membrane receptor IRE1?, leading to increased caspase-2 levels via degradation of microRNAs, and consequently induction of apoptosis. This observation casts caspase-2 into a central role in the apoptosis triggered by ER stress. We have used multiple cell types from caspase-2-deficient mice to test this hypothesis but failed to find significant impact of loss of caspase-2 on ER-stress-induced apoptosis. Moreover, we did not observe increased expression of caspase-2 protein in response to ER stress. Our data strongly argue against a critical role for caspase-2 in ER-stress-induced apoptosis.

SUBMITTER: Sandow JJ

PROVIDER: S-EPMC3921595 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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ER stress does not cause upregulation and activation of caspase-2 to initiate apoptosis.

Sandow J J JJ Dorstyn L L O'Reilly L A LA Tailler M M Kumar S S Strasser A A Ekert P G PG

Cell death and differentiation 20131129 3

A recent report claimed that endoplasmic reticulum (ER) stress activates the ER trans-membrane receptor IRE1α, leading to increased caspase-2 levels via degradation of microRNAs, and consequently induction of apoptosis. This observation casts caspase-2 into a central role in the apoptosis triggered by ER stress. We have used multiple cell types from caspase-2-deficient mice to test this hypothesis but failed to find significant impact of loss of caspase-2 on ER-stress-induced apoptosis. Moreover ...[more]

PMID: 24292555

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