Plays an important role in the functional organization of mitotic chromosomes. Exhibits low basal ATPase activity, and unable to polymerize. Proposed core component of the chromatin remodeling INO80 complex which is involved in transcriptional regulation, DNA replication and probably DNA repair. Required for the recruitment of INO80 (and probably the INO80 complex) to sites of DNA damage. Strongly prefer nucleosomes and H3-H4 tetramers over H2A-H2B dimers, suggesting it may act as a nucleosome recognition module within the complex. Component of the chromatin remodeling INO80 complex; specifically part of a complex module associated with the DBINO domain of INO80. Interacts with ACTR5; the interaction is observed in asynchronous (interphase) cells but not in metaphase-arrested cells indicative for a possible dissociation of the INO80 complex in mitotic cells. Exists as monomers and dimers, but the dimer is most probably the biologically relevant form required for stable interactions with histones that exploits the twofold symmetry of the nucleosome core. Specifically localizes to mitotic chromosomes. Belongs to the actin family. ARP8 subfamily. Truncated N-terminus.