Regulatory subunit of the ATP-dependent BRF-1 and BRF-5 ISWI chromatin remodeling complexes, which form ordered nucleosome arrays on chromatin and facilitate access to DNA during DNA-templated processes such as DNA replication, transcription, and repair (PubMed:28801535). Both complexes regulate the spacing of nucleosomes along the chromatin and have the ability to slide mononucleosomes to the center of a DNA template (PubMed:28801535). The BRF-1 ISWI chromatin remodeling complex has a lower ATP hydrolysis rate than the BRF-5 ISWI chromatin remodeling complex (PubMed:28801535). Chromatin reader protein, which may play a role in transcriptional regulation via interaction with ISWI (By similarity) (PubMed:10662543). Involved in positively modulating the rate of age-related behavioral deterioration (By similarity). Represses the expression of mitochondrial function-related genes, perhaps by occupying their promoter regions, working in concert with histone methyltransferase EHMT1 (By similarity). {ECO:0000250|UniProtKB:A2AUY4, ECO:0000269|PubMed:28801535, ECO:0000303|PubMed:10662543}. This is the function of BAZ2B (bromodomain adjacent to zinc finger domain 2B, ENSG00000123636).