H3K23ac

[1] The regulation of transcription factors, effector proteins, molecular chaperones, and cytoskeletal proteins by acetylation and deacetylation is a significant post-translational regulatory mechanism[2] These regulatory mechanisms are analogous to phosphorylation and dephosphorylation by the action of kinases and phosphatases.

Not only can the acetylation state of a protein modify its activity but there has been recent suggestion that this post-translational modification may also crosstalk with phosphorylation, methylation, ubiquitination, sumoylation, and others for dynamic control of cellular signaling.

[3][4][5] In the field of epigenetics, histone acetylation (and deacetylation) have been shown to be important mechanisms in the regulation of gene transcription.

[9] The current understanding and interpretation of histones comes from two large scale projects: ENCODE and the Epigenomic roadmap.

This led to chromatin states which define genomic regions by grouping the interactions of different proteins and/or histone modifications together.

Chromatin states were investigated in Drosophila cells by looking at the binding location of proteins in the genome.

[12] A look in to the data obtained led to the definition of chromatin states based on histone modifications.

This additional level of annotation allows for a deeper understanding of cell specific gene regulation.