Membrane remodeling during embryonic abscission inCaenorhabditis elegans.
Abscission is the final step of cytokinesis and results in the physical separation of two daughter cells. In this study, we conducted a time-resolved series of electron tomographic reconstructions to define the steps required for the first embryonic abscission inCaenorhabditis elegansOur findings indicate that membrane scission occurs on both sides of the midbody ring with random order and that completion of the scission process requires actomyosin-driven membrane remodeling, but not microtubules. Moreover, continuous membrane removal predominates during the late stages of cytokinesis, mediated by both dynamin and the ESCRT (endosomal sorting complex required for transport) machinery. Surprisingly, in the absence of ESCRT function inC. elegans, cytokinetic abscission is delayed but can be completed, suggesting the existence of parallel membrane-reorganizing pathways that cooperatively enable the efficient severing of cytoplasmic connections between dividing daughter cells.
Experimental Center, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany.
Julia
0000-0002-3526-0211
J
König
Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53706.
E B
0000-0002-8154-7774
EB
Frankel
Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53706 mueller-reichert@tu-dresden.de audhya@wisc.edu.
Anjon
0000-0002-7828-5152
A
Audhya
Experimental Center, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany mueller-reichert@tu-dresden.de audhya@wisc.edu.
Thomas
0000-0003-0203-1436
T
Müller-Reichert
D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology*; D002462:Cell Membrane / Q000378:metabolism*; D048749:Cytokinesis; D003599:Cytoskeleton / Q000378:metabolism*; D008954:Models, Biological