The protein kinase PKR: a molecular clock that sequentially activates survival and death programs.

ABSTRACT: Cell death and survival play a key role in the immune system as well as during development. The control mechanisms that balance cell survival against cell death are not well understood. Here we report a novel strategy used by a single protein to regulate chronologically cell survival and death. The interferon-induced protein kinase PKR acts as a molecular clock by using catalysis-dependent and -independent activities to temporally induce cell survival prior to cell death. We show that the proapoptotic protein PKR surprisingly activates a survival pathway, which is mediated by NF-kappaB to delay apoptosis. Cell death is then induced by PKR through the phosphorylation of eIF-2alpha. This unique temporal control might serve as a paradigm for other kinases whose catalytic activity is not requi

SUBMITTER: Donze O 

PROVIDER: S-EPMC1271809 | biostudies-literature | 2004 Feb

REPOSITORIES: biostudies-literature