ATP-dependent helicase that binds and distorts nucleosomal DNA.Acts as a component of the histone deacetylase NuRD complex which participates in the remodeling of chromatin (PubMed:16428440, PubMed:17626165, PubMed:28977666.Localizes to acetylated damaged chromatin in a ZMYND8-dependent manner, to promote transcriptional repression and double-strand break repair by homologous recombination.