Component of the NuA4 histone acetyltransferase (HAT) complex, a multiprotein complex involved in transcriptional activation of select genes principally by acetylation of nucleosomal histones H4 and H2A (PubMed:28694333). The NuA4 complex plays a direct role in repair of DNA double-strand breaks (DSBs) by promoting homologous recombination (HR) (By similarity). The NuA4 complex is also required for spermatid development by promoting acetylation of histones: histone acetylation is required for histone replacement during the transition from round to elongating spermatids (PubMed:28694333). In the NuA4 complex, EPC1 is required to recruit MBTD1 into the complex (By similarity). Component of the NuA4 histone acetyltransferase complex which contains the catalytic subunit KAT5/TIP60 and the subunits EP400, TRRAP/PAF400, BRD8/SMAP, EPC1, DMAP1/DNMAP1, RUVBL1/TIP49, RUVBL2, ING3, actin, ACTL6A/BAF53A, MORF4L1/MRG15, MORF4L2/MRGX, MRGBP, YEATS4/GAS41, VPS72/YL1 and MEAF6 (By similarity). KAT5/TIP60, EPC1, and ING3 together constitute a minimal HAT complex termed Piccolo NuA4 (By similarity). Component of a NuA4-related complex which contains EP400, TRRAP/PAF400, SRCAP, BRD8/SMAP, EPC1, DMAP1/DNMAP1, RUVBL1/TIP49, RUVBL2, actin, ACTL6A/BAF53A, VPS72 and YEATS4/GAS41 (By similarity). Interacts with TRIM27 (By similarity). Interacts with MBTD1; interaction is direct and promotes recruitment of MBTD1 into the NuA4 histone acetyltransferase complex (By similarity). Expressed in adult brain, heart, kidney, liver, lung, skeletal muscle and testis (PubMed:9735366). Expressed in male germ cells, present in round spermatids of steps 1 to 4 (PubMed:28694333). Mice are viable but display growth retardation, homeotic transformations of the axis and sterility in both males and females (PubMed:28694333). Male sterility is caused by defects in generation of elongating spermatids (PubMed:28694333). Belongs to the enhancer of polycomb family.