Author/Authors :
Shridar Ganesan، نويسنده , , Daniel P. Silver، نويسنده , , Roger A. Greenberg، نويسنده , , Dror Avni، نويسنده , , Ronny Drapkin، نويسنده , , Alexander Miron، نويسنده , , Samuel C. Mok، نويسنده , , Voahangy Randrianarison، نويسنده , , Steven Brodie، نويسنده , , Jennifer Salstrom، نويسنده , , Theodore P. Rasmussen، نويسنده , , Ann Klimke، نويسنده , , Christine Marrese، نويسنده , , York Marahrens، نويسنده , , Chu-Xia Deng، نويسنده , , Jean Feunteun، نويسنده , , David M. Livingston، نويسنده ,
Abstract :
BRCA1, a breast and ovarian tumor suppressor, colocalizes with markers of the inactive X chromosome (Xi) on Xi in female somatic cells and associates with XIST RNA, as detected by chromatin immunoprecipitation. Breast and ovarian carcinoma cells lacking BRCA1 show evidence of defects in Xi chromatin structure. Reconstitution of BRCA1-deficient cells with wt BRCA1 led to the appearance of focal XIST RNA staining without altering XIST abundance. Inhibiting BRCA1 synthesis in a suitable reporter line led to increased expression of an otherwise silenced Xi-located GFP transgene. These observations suggest that loss of BRCA1 in female cells may lead to Xi perturbation and destabilization of its silenced state.
