**Mononucleosomes (H3.3 K27M), Recombinant Human

Recombinant human histone H3.3 (H3F3A, H3.3A, H3F3, accession P84243) containing a methionine at position 27, expressed in E. coli. Histone H3 is one of the four proteins that are present in the nucleosome, the basic repeating unit subunit of chromatin, consisting of 147 base pairs of DNA wrapped around an octamer of core histone proteins (H2A, H2B, H3 and H4). H3.3 is a histone variant, a allelelic replacement histone found in regions of high chromatin turnover outside of S-phase (e.g. at actively transcribed genes). The substitution of M for K at position 27 in human H3.1 and H3.3 is a dominant negative inhibitor of the EZH2 methyltransferase complex PRC2 and is associated with pediatric brain cancer (DIPG).