BRCA1 Protein

The phosphoprotein encoded by the BRCA1 gene (GENE, BRCA1). It contains an N-terminal RING FINGER DOMAIN and is a PROTEIN PHOSPHATASE 1 regulatory subunit. In normal cells the BRCA1 protein is localized in the nucleus, whereas in the majority of breast cancer cell lines and in malignant pleural effusions from breast cancer patients, it is localized mainly in the cytoplasm. (Science 1995;270(5237):713,789-91)