The Apaf-1Kprocaspase-9 apoptosome complex functions as a proteolytic-based molecular timer
نویسندگان
چکیده
Srinivas Malladi, Madhavi Challa-Malladi, Howard O Fearnhead and Shawn B Bratton* Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA and Caspase Laboratory, National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland
منابع مشابه
The Apaf-1*procaspase-9 apoptosome complex functions as a proteolytic-based molecular timer.
During stress-induced apoptosis, the initiator caspase-9 is activated by the Apaf-1 apoptosome and must remain bound to retain significant catalytic activity. Nevertheless, in apoptotic cells the vast majority of processed caspase-9 is paradoxically observed outside the complex. We show herein that apoptosome-mediated cleavage of procaspase-9 occurs exclusively through a CARD-displacement mecha...
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Autocatalytic activation of an initiator caspase triggers the onset of apoptosis. In dying cells, caspase-9 activation is mediated by a multimeric adaptor complex known as the Apaf-1 apoptosome. The molecular mechanism by which caspase-9 is activated by the Apaf-1 apoptosome remains largely unknown. Here we demonstrate that the previously reported 1:1 interaction between Apaf-1 caspase recruitm...
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تاریخ انتشار 2009