The function of ZMYND11 (zinc finger MYND-type containing 11, Ensembl gene identifier ENSG00000015171) is as follows. Chromatin reader that specifically recognizes and binds histone H3.3 trimethylated at 'Lys-36' (H3.3K36me3) and regulates RNA polymerase II elongation. Does not bind other histone H3 subtypes (H3.1 or H3.2) (By similarity). Colocalizes with highly expressed genes and functions as a transcription corepressor by modulating RNA polymerase II at the elongation stage. Binds non-specifically to dsDNA (PubMed:24675531). Acts as a tumor-suppressor by repressing a transcriptional program essential for tumor cell growth. {ECO:0000250|UniProtKB:Q8R5C8, ECO:0000269|PubMed:10734313, ECO:0000269|PubMed:16565076, ECO:0000269|PubMed:24675531}. (Microbial infection) Inhibits Epstein-Barr virus EBNA2- mediated transcriptional activation and host cell proliferation, through direct interaction. .