Actin-myosin-based contraction is responsible for apoptotic nuclear disintegration.

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Authors

Croft, DR
Coleman, ML
Li, S
Robertson, D
Sullivan, T
Stewart, CL
Olson, MF

Document Type

Journal Article

Date

2005-01

Date Accepted

Date Available

Abstract

Membrane blebbing during the apoptotic execution phase results from caspase-mediated cleavage and activation of ROCK I. Here, we show that ROCK activity, myosin light chain (MLC) phosphorylation, MLC ATPase activity, and an intact actin cytoskeleton, but not microtubular cytoskeleton, are required for disruption of nuclear integrity during apoptosis. Inhibition of ROCK or MLC ATPase activity, which protect apoptotic nuclear integrity, does not affect caspase-mediated degradation of nuclear proteins such as lamins A, B1, or C. The conditional activation of ROCK I was sufficient to tear apart nuclei in lamin A/C null fibroblasts, but not in wild-type fibroblasts. Thus, apoptotic nuclear disintegration requires actin-myosin contractile force and lamin proteolysis, making apoptosis analogous to, but distinct from, mitosis where nuclear disintegration results from microtubule-based forces and from lamin phosphorylation and depolymerization.

Citation

The Journal of cell biology, 2005, 168 (2), pp. 245 - 255

Source Title

Publisher

ISSN

0021-9525

eISSN

1540-8140

Research Team

Genetic Susceptibility

Notes