Histone proteins H2A, H2B, H3 and H4 form an octamer, which is composed of two copies of each of them. The octamer is wrapped with DNA to be a nucleosome. The N-terminal region of each histone proteins in nucleosomes has many post-translational modifications (PTMs), such as methylation, acetylation, phosphorylation and ubiquitination. The pattern of modification is changed by the living circumstances, diseases and food, which results in the change of epigenetic regulation of genes.
Recently, an unusual modification of histone was found [1]: an O-palmitoylation of histone H4 of Ser47. This highly hydrophobic modification will change the property of highly basic histone and will lead to the discovery of the novel function of histone modification. Thus, we established a method to synthesize O-palmitoylated H4 and attempted its function. In my presentation, I will talk about the results of the synthesis, conformational analysis and in-cell study of the O-palmitoylated H4 [2].
On the other hand, we have been engaged in the functional analysis of heterochromatin protein (HP1), which binds to trimethylated Lys9 of histone H3 to promote the formation of heterochromatin structure. In my second talk, the effect of the site-specific phosphorylation of the N-terminus on the dynamics of HP1 protein will be discussed [3].