The function of YEATS4 (YEATS domain containing 4, ENSG00000127337) is as follows. Chromatin reader component of the NuA4 histone acetyltransferase (HAT) complex, a complex involved in transcriptional activation of select genes principally by acetylation of nucleosomal histones H4 and H2A (PubMed:12963728, PubMed:14966270). Specifically recognizes and binds acylated histone H3, with a preference for histone H3 diacetylated at 'Lys-18' and 'Lys-27' (H3K18ac and H3K27ac) or histone H3 diacetylated at 'Lys-14' and 'Lys-27' (H3K14ac and H3K27ac) (PubMed:29437725, PubMed:29900004, PubMed:30071723). Also able to recognize and bind crotonylated histone H3 (PubMed:30071723). May also recognize and bind histone H3 succinylated at 'Lys-122' (H3K122succ); additional evidences are however required to confirm this result in vivo (PubMed:29463709). Plays a key role in histone variant H2AZ1/H2A.Z deposition into specific chromatin regions: recognizes and binds H3K14ac and H3K27ac on the promoters of actively transcribed genes and recruits NuA4-related complex to deposit H2AZ1/H2A.Z (PubMed:29437725). H2AZ1/H2A.Z deposition is required for maintenance of embryonic stem cell (By similarity). {ECO:0000250|UniProtKB:Q9CR11, ECO:0000269|PubMed:12963728, ECO:0000269|PubMed:14966270, ECO:0000269|PubMed:29437725, ECO:0000269|PubMed:29463709, ECO:0000269|PubMed:29900004, ECO:0000269|PubMed:30071723}.