摘要Histone H2A monoubiquitination is associated with transcriptional repression and needs to be removed by deubiquitinases to facilitate gene transcription in eukaryotes.However,the deubiquitinase responsible for genome-wide H2A deubiquitination in plants has yet to be identified.In this study,we found that the previously identified PWWP-EPCR-ARID-TRB(PEAT)complex components interact with both the ubiquitin-specific protease UBP5 and the redundant histone acetyltransferases HAM1 and HAM2(HAM1/2)to form a larger version of PEAT complex in Arabidopsis thaliana.UBP5 functions as an H2A deubiquitinase in a nucleosome substrate-dependent manner in vitro and mediates H2A deubiquitination at the whole-genome level in vivo.HAM1/2 are shared subunits of the PEAT complex and the conserved NuA4 histone acetyltransferase com-plex,and are responsible for histone H4K5 acetylation.Within the PEAT complex,the PWWP components(PWWP1,PWWP2,and PWWP3)directly interact with UBP5 and are necessary for UBP5-mediated H2A deu-biquitination,while the EPCR components(EPCR1 and EPCR2)directly interact with HAM1/2 and are required for HAM1/2-mediated H4K5 acetylation.Collectively,our study not only identifies dual roles of the PEAT com-plex in H2A deubiquitination and H4K5 acetylation but also illustrates how these processes collaborate at the whole-genome level to regulate the transcription and development in plants.