Histones undergo many post-translational modifications, such as methylation and acetylation, to regulate epigenetic transcription and gene expression. In the process of post-translational modification of histones, the enzymes responsible for the addition or deletion of these epigenetic marks are often referred to as “writers” and “erasers”, respectively. For example, in histone methylation, histone methyltransferase adds methyl markers to certain specific amino acids of histones, while histone demethylase is responsible for removing these markers. When histone acetylation occurs, histone acetyltransferase catalyzes the addition of acetyl groups, while histone deacetylase is responsible for the removal of acetylation markers. There are also proteins with specific reader domains selectively recognize different histone modifications, which are called “readers”.