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PubMed · 9207057

BRCA1 is a cell cycle-regulated nuclear phosphoprotein.

H Ruffner·I M Verma
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Abstract

We have characterized the BRCA1 gene product by using four polyclonal antibodies raised against peptides from four different regions of the protein. The antibodies specifically recognize an approximately 220-kDa BRCA1 protein that is predominantly expressed in the nucleus of both normal and neoplastic breast cancer cells. It is a serine phosphoprotein that undergoes hyperphosphorylation during late G1 and S phases of the cell cycle and is transiently dephosphorylated early after M phase. We propose that BRCA1 is a phosphoprotein that alters in a qualitative and quantitative manner during cell cycle progression.

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AntibodiesBRCA1 ProteinBreast NeoplasmsCell Cycle ProteinsFemaleHeLa CellsHumansNuclear ProteinsPhosphoproteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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H Ruffner, I M Verma. 1997-07-08. BRCA1 is a cell cycle-regulated nuclear phosphoprotein.. https://doi.org/10.1073/pnas.94.14.7138

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