MDC1 (F6C8T) Rabbit Monoclonal Antibody #79210

Mediator of DNA damage checkpoint protein 1 (MDC1) is a scaffold protein that plays a central role in the early stages of the DNA damage response (DDR) and helps to maintain genomic stability (1). It is among the first proteins to accumulate at sites of DNA double-strand breaks (DSBs), where it forms a complex with phosphorylated histone H2AX (γ-H2AX), protecting its C-terminal tail from premature dephosphorylation until DSB repair is complete (1,2). Through phosphorylation-dependent interactions, MDC1 recruits DNA damage responsive E3 ubiquitin ligase RNF8, which ubiquitinates histones H2A and H2AX, leading to the accumulation of repair proteins, including 53BP1 and BRCA1, at the damage site (2-5). MDC1 also recruits E3 ubiquitin ligases Pellino-1 and -2 to DNA DSB sites and is essential for DNA damage-induced cell cycle arrest at the S and G2/M checkpoints (4-6).

Due to its critical role in the DDR, MDC1 expression levels are being studied in relation to various cancers. Studies have shown that MDC1 may function as a tumor suppressor and MDC1 loss or reduction correlates with later-stage tumors, highlighting its potential as a biomarker for prognosis and therapeutic response (1,5).