We recently demonstrated that WRAP53β acts as a key regulator of ubiquitin-dependent repair of DNA double-strand breaks. Here, we applied the proximity ligation assay (PLA) to show that at such breaks WRAP53β accumulates in close proximity to γH2AX and, furthermore as demonstrated by their co-immunoprecipitation (IP) binds to γH2AX, in a manner dependent on the ATM and ATR kinases. Moreover, fo...

DNA interstrand crosslinks (ICLs) are toxic lesions that block the progression of replication and transcription. CtIP is a conserved DNA repair protein that facilitates DNA end resection in the double-strand break (DSB) repair pathway. Here we show that CtIP plays a critical role during initiation of ICL processing in replicating human cells that is distinct from its role in DSB repair. CtIP de...

Cellular senescence is an irreversible growth arrest caused by oxidative stress and DNA damage ultraviolet radiation mediated cellular responsible for skin photoaging. The Type 17 collagen (COL17A1) expressed in epithelial hemidesmosomes plays a crucial role maintaining hair follicle stem cells. Apocynin, (1-(4-Hydroxy-3-methoxyphenyl)ethan-1-one)) chemical inducer of Collagen 17A1 which promot...

The polycomb group protein BMI1 is a component of the polycomb repressive complex 1 (PRC1). Although lacking enzymatic activity, BMI1 makes an important contribution to the intrinsic E3 ubiquitin ligase activity of PRC1 via binding of the catalytic subunit RING2. PRC1 catalyzes mono-ubiquitination of histone H2A at lysine 119 (H2AK119Ub), a well-recognized epigenetic marker associated with gene...

BRCA1, which is mutated in the familial forms of breast and ovarian cancer, plays important roles in genome stability through its participation in DNA damage response (DDR) following double-stranded breaks (DsBs). BRCA1 activates the checkpoint pathway to retard cell cycle progression and stimulates repair of the DsBs (reviewed in ref. 1). it is recruited to the damaged chromatin through an int...