Abstract
Breast Cancer Type 1 Susceptibility Protein (BRCA)-1 existing in several functionally distinct complexes, promotes DNA repair of DNA double-strand breaks (DSBs). A recent study by Tang and colleagues identifies the lysine methyltransferase Disruptor of Telomeric Silencing 1-Like (DOT1L) involved in modifying Receptor-Associated Protein 80 (RAP80) to promote BRCA1-A complex localization and repair functions at DNA breaks. This study illuminates a potential therapeutic target for cancer radiotherapy.