Format

Send to

Choose Destination
See comment in PubMed Commons below
Curr Biol. 2015 Jul 20;25(14):1924-31. doi: 10.1016/j.cub.2015.06.001. Epub 2015 Jun 25.

SPD-2/CEP192 and CDK Are Limiting for Microtubule-Organizing Center Function at the Centrosome.

Author information

1
Department of Biology, Stanford University, Stanford, CA 94305, USA.
2
Department of Biology, Stanford University, Stanford, CA 94305, USA. Electronic address: feldmanj@stanford.edu.

Abstract

The centrosome acts as the microtubule-organizing center (MTOC) during mitosis in animal cells. Microtubules are nucleated and anchored by γ-tubulin ring complexes (γ-TuRCs) embedded within the centrosome's pericentriolar material (PCM). The PCM is required for the localization of γ-TuRCs, and both are steadily recruited to the centrosome, culminating in a peak in MTOC function in metaphase. In differentiated cells, the centrosome is often attenuated as an MTOC and MTOC function is reassigned to non-centrosomal sites such as the apical membrane in epithelial cells, the nuclear envelope in skeletal muscle, and down the lengths of axons and dendrites in neurons. Hyperactive MTOC function at the centrosome is associated with epithelial cancers and with invasive behavior in tumor cells. Little is known about the mechanisms that limit MTOC activation at the centrosome. Here, we find that MTOC function at the centrosome is completely inactivated during cell differentiation in C. elegans embryonic intestinal cells and MTOC function is reassigned to the apical membrane. In cells that divide after differentiation, the cellular MTOC state switches between the membrane and the centrosome. Using cell fusion experiments in live embryos, we find that the centrosome MTOC state is dominant and that the inactive MTOC state of the centrosome is malleable; fusion of a mitotic cell to a differentiated or interphase cell results in rapid reactivation of the centrosome MTOC. We show that conversion of MTOC state involves the conserved centrosome protein SPD-2/CEP192 and CDK activity from the mitotic cell.

PMID:
26119750
DOI:
10.1016/j.cub.2015.06.001
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center