Death-receptor activation halts clathrin-dependent endocytosis

doi:10.1073/pnas.0604044103

Death-receptor activation halts clathrin-dependent endocytosis

*Departments of Research Administration, Molecular Oncology, and Protein Chemistry, Genentech, Inc., South San Francisco, CA 94080; and
^§Cell Microscopy Center, Department of Cell Biology and Institute for Biomembranes, University Medical Center Utrecht, 3584CX, Utrecht, The Netherlands

Contributed by Richard H. Scheller, May 18, 2006
↵ ^†C.D.A. and D.A.L. contributed equally to this work.

Abstract

Endocytosis is crucial for various aspects of cell homeostasis. Here, we show that proapoptotic death receptors (DRs) trigger selective destruction of the clathrin-dependent endocytosis machinery. DR stimulation induced rapid, caspase-mediated cleavage of key clathrin-pathway components, halting cellular uptake of the classic cargo protein transferrin. DR-proximal initiator caspases cleaved the clathrin adaptor subunit AP2α between functionally distinct domains, whereas effector caspases processed clathrin’s heavy chain. DR5 underwent ligand-induced, clathrin-mediated endocytosis, suggesting that internalization of DR signaling complexes facilitates clathrin-pathway targeting by caspases. An endocytosis-blocking, temperature-sensitive dynamin-1 mutant attenuated DR internalization, enhanced caspase stimulation downstream of DRs, and increased apoptosis. Thus, DR-triggered caspase activity disrupts clathrin-dependent endocytosis, leading to amplification of programmed cell death.

Footnotes

^¶To whom correspondence may be addressed. E-mail: aa{at}gene.com or scheller{at}gene.com
↵ ^‡Present address: Cambridge Institute for Medical Research, University of Cambridge, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, United Kingdom.
Author contributions: C.D.A., D.A.L., A.A.P., and A.A. designed research; C.D.A., D.A.L., E.E.V., K.T., A.M.D.M., J.K., D.A., and V.P. performed research; C.D.A. and A.A.P. contributed new reagents/analytic tools; C.D.A., D.A.L., A.A.P., R.H.S., and A.A. analyzed data; and C.D.A., D.A.L., and A.A. wrote the paper.
Conflict of interest statement: No conflicts declared.
Abbreviations:

Abbreviations:

Apo2L/TRAIL,

Apo2 ligand/TNF-related apoptosis-inducing ligand;

CHC,

clathrin heavy chain;

DISC,

death-inducing signaling complex;

DR,

death receptor;

PM,

plasma membrane;

Tf,

transferrin;

zVAD-fmk,

N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone.
Freely available online through the PNAS open access option.