BRCA1 protein is linked to the RNA polymerase II holoenzyme complex via RNA helicase A.
The breast cancer specific tumour suppressor protein, BRCA1 (refs 1,2), activates transcription when linked with a DNA-binding domain and is a component of the RNA polymerase II (Pol II) holoenzyme. We show here that RNA helicase A (RHA) protein links BRCA1 to the holoenzyme complex. The region of BRCA1 which interacts with RHA and, thus, the holoenzyme complex, corresponds to subregions of the BRCT domain of BRCA1 (ref. 9). This interaction was shown to occur in yeast nuclei, and expression in human cells of a truncated RHA molecule which retains binding to BRCA1 inhibited transcriptional activation mediated by the BRCA1 carboxy terminus. These data are the first to identify a specific protein interaction with the BRCA1 C-terminal domain and are consistent with the model that BRCA1 functions as a transcriptional coactivator.
Anderson
S F
SF
Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
Schlegel
B P
BP
Nakajima
T
T
Wolpin
E S
ES
Parvin
J D
JD
D000818:Animals; D019313:BRCA1 Protein / Q000235:genetics / Q000378:metabolism*; D003067:Coenzymes / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D016296:Mutagenesis; D020365:RNA Helicases; D012316:RNA Nucleotidyltransferases / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
D019313:BRCA1 Protein; D003067:Coenzymes; D011993:Recombinant Fusion Proteins; D012316:RNA Nucleotidyltransferases; D012319:RNA Polymerase II; D020365:RNA Helicases