Caspase-3-mediated cleavage of ROCK I induces MLC phosphorylation and apoptotic membrane blebbing

  title={Caspase-3-mediated cleavage of ROCK I induces MLC phosphorylation and apoptotic membrane blebbing},
  author={Michael Sebbagh and Claire Renvoiz{\'e} and Jocelyne Hamelin and Nicole Le Riche and Jacques Bertoglio and Jacqueline Bréard},
  journal={Nature Cell Biology},
Increased phosphorylation of myosin light chain (MLC) is necessary for the dynamic membrane blebbing that is observed at the onset of apoptosis. Here we identify ROCK I, an effector of the small GTPase Rho, as a new substrate for caspases. ROCK I is cleaved by caspase-3 at a conserved DETD1113/G sequence and its carboxy-terminal inhibitory domain is removed, resulting in deregulated and constitutive kinase activity. ROCK proteins are known to regulate MLC-phosphorylation, and apoptotic cells… 
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