Format

Send to

Choose Destination
Cancer Biol Ther. 2007 Dec;6(12):1853-7. Epub 2007 Oct 13.

BRCA1 regulates gamma-tubulin binding to centrosomes.

Author information

1
Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.

Abstract

Centrosomes are the cellular organelles that nucleate microtubules (MTs) via the activity of gamma-tubulin ring complex(s) (gammaTuRC) bound to the pericentriolar material of the centrosomes. BRCA1, the breast and ovarian cancer specific tumor suppressor, inhibits centrosomal MT nucleation via its ubiquitin ligase activity, and one of the known BRCA1 substrates is the key gammaTuRC component, gamma-tubulin. We analyzed the mechanism by which BRCA1 regulates centrosome function using an in vitro reconstitution assay, which includes separately staged steps. Our results are most consistent with a model by which the BRCA1 ubiquitin ligase modifies both gamma-tubulin plus a second centrosomal protein that controls localization of gammaTuRC to the centrosome. We suggest that this second protein is an adapter protein or protein complex that docks gamma-TuRC to the centrosome. By controlling gamma-TuRC localization, BRCA1 appropriately inhibits centrosome function, and loss of BRCA1 would result in centrosome hyperactivity, supernumerary centrosomes and, possibly, aneuploidy.

PMID:
18087219
PMCID:
PMC2643382
DOI:
10.4161/cbt.6.12.5164
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Taylor & Francis Icon for PubMed Central
Loading ...
Support Center