Probable catalytic component of a chromatin-remodeling complex which mediates the ATP-dependent exchange of histone H2A variant H2AV/htz-1 for H2A, leading to transcriptional regulation of selected genes by chromatin remodeling. Involved in foregut development, and may be involved in vulval development. Defects in feminization. Embryonic arrest. Belongs to the SNF2/RAD54 helicase family. SWR1 subfamily.