DNA-binding component of the FA core complex involved in DNA damage repair and genome maintenance. Required for optimal chromatin association of the FA core complex. Required for efficient damage-induced monoubiquitination and focus formation of FANCD2. Stabilizes FAAD24; FANCM and STRA13/CENPX in the FA core complex. Plays a role in DNA interstrand cross-linking (ICL) repair and in recovery of replication forks stalled by topoisomerase I-DNA cleavage intermediates induced by camptothecin. Component of the heterotetrameric CENP-T-W-S-X complex that binds and supercoils DNA; and plays an important role in kinetochore assembly. Component of the APITD1/CENPS complex that is essential for the stable assembly of the outer kinetochore. Plays an important role in mitotic progression and chromosome segregation. Component of the CENPA-CAD (nucleosome distal) complex; a complex recruited to centromeres which is involved in assembly of kinetochore proteins; mitotic progression and chromosome segregation. {ECO:0000269|PubMed:19620631; ECO:0000269|Ref.7; ECO:0000269|Ref.8}.