Component of the NuA4 histone acetyltransferase complex which is involved in transcriptional activation of selected genes principally by acetylation of nucleosomal histone H4 and H2A. The NuA4 complex is also involved in DNA repair (By similarity). Also involved in deacetylation of histones, chromatin assembly and chromosome segregation. May act as a transcriptional oscillator, directing histone deacetylases to specific chromosomal domains. Component of the NuA4 histone acetyltransferase complex (By similarity). Heterotetramer of alp13, clr6, prw1 and pst2. Belongs to the MRG family.