gamma H2AX:MDC1/NFBD1 complex at site of DNA double-strand break gamma H2AX-coated DNA double-strand break ends MDC1/NFBD1associates with gamma H2AX at nuclear foci Authored: Matthews, L, 2003-11-18 00:00:00 Pubmed12607003 Pubmed12607005 Reactome Database ID Release 4383560 Reactome, http://www.reactome.org ReactomeREACT_1809 Recruitment of MDC1 to nuclear foci is mediated by H2AX. MDC1 forms complexes with phosphorylated H2AX, promotes efficient phosphorylation of H2AX and controls the formation of BRCA1 and MRN foci (Stewart et al.,2003).