Structural peculiarities of the (MHF1-MHF2)4 octamer provide a long DNA binding patch to anchor the MHF-FANCM complex to chromatin: A solution SAXS study

MHF1 and MHF2 are histone-fold-containing FANCM-associated proteins. FANCM is a Fanconi anemia (FA) complementation group protein. We previously obtained high-resolution structures of MHF1-MHF2 (MHF) and MHF in complex with a fragment of FANCM (MHF-FANCM-F). Here, we use small angle X-ray scattering (SAXS) to investigate the solution behaviors of these protein complexes. In combination with crystallographic data, the results of the SAXS study reveal that a long, positively charged patch exposed on the surface of the MHF complex plays a critical role in double-stranded DNA (dsDNA) binding.