First published online January 23, 2008
Journal of Cell Science 121, 304e (2008)
© The Company of Biologists Limited
Cytokinesis: furrows without a spindle
The formation of a cleavage furrow on the cell surface is the first step in cytokinesis, the final act in mitosis. The orientation of the mitotic spindle determines where the cleavage furrow will form, but which spindle component controls this process? Classical experiments conducted in the 1960s and 1970s – in which cell division was monitored in echinoderm eggs that had been enucleated or forced into a doughnut shape – suggested that astral microtubules control the site of furrowing. However, more recent work in C. elegans and cultured cells implicates the central spindle as the main determinant of the furrow site. Now, George von Dassow and colleagues (p. 306) recapitulate a series of early experiments, using cells in early C. elegans embryos. By visualising membrane invagination and contractile ring formation (using GFP-labelled myosin), the authors show that cleavage furrows can form in doughnut-shaped cells, even when the central spindle is abolished by knocking down the microtubule-associated protein SPD-1. Surprisingly, anucleate cells are also capable of furrow formation. However, cytokinesis often fails to complete when the central spindle is perturbed or mislocated. These data indicate that astral microtubules and the central spindle are both important for successful cell division, and shed light on the longstanding question of how cytokinesis is controlled.

CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
Related articles in JCS:
- Cytokinetic furrowing in toroidal, binucleate and anucleate cells in C. elegans embryos
- Jalal K. Baruni, Edwin M. Munro, and George von Dassow
JCS 2008 121: 306-316.
[Abstract]
[Full Text]