Rvb1p and Rvb2p are essential components of a chromatin remodeling complexthat regulates transcription of over 5% of yeast genes

Eukaryotic Rvb1p and Rvb2p are two highly conserved proteins related to the helicase subset of the AAA+ family of ATPases. Conditional mutants in both genes show rapid changes in the transcription of over 5% of yeast genes, w ith a similar number of genes being repressed and activated. Both Rvb1p and Rvb2p are required for maintaining the induced state of many inducible pro moters. ATP binding and hydrolysis by Rvb1p and Rvb2p is individually essen tial in vivo, and the two proteins are associated with each other in a high molecular weight complex that shows ATP-dependent chromatin remodeling act ivity in vitro. Our findings show that Rvb1p and Rvb2p are essential compon ents of a chromatin remodeling complex and determine genes regulated by the complex.