Format

Send to

Choose Destination
Science. 2006 Mar 31;311(5769):1887-93. Epub 2006 Mar 16.

A mitotic lamin B matrix induced by RanGTP required for spindle assembly.

Author information

1
Department of Embryology, Carnegie Institution of Washington and Howard Hughes Medical Institute, Baltimore, MD 21218, USA.

Abstract

Mitotic spindle morphogenesis is a series of highly coordinated movements that lead to chromosome segregation and cytokinesis. We report that the intermediate filament protein lamin B, a component of the interphase nuclear lamina, functions in spindle assembly. Lamin B assembled into a matrix-like network in mitosis through a process that depended on the presence of the guanosine triphosphate-bound form of the small guanosine triphosphatase Ran. Depletion of lamin B resulted in defects in spindle assembly. Dominant negative mutant lamin B proteins that disrupt lamin B assembly in interphase nuclei also disrupted spindle assembly in mitosis. Furthermore, lamin B was essential for the formation of the mitotic matrix that tethers a number of spindle assembly factors. We propose that lamin B is a structural component of the long-sought-after spindle matrix that promotes microtubule assembly and organization in mitosis.

PMID:
16543417
DOI:
10.1126/science.1122771
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center