Histone methylation causes transcription repression or activation, depending on the target sites. Histone methyltransferases (HMTs) control or regulate DNA methylation through chromatin-dependent transcription repression or activation. Measurement of histone methyltrasferase activity and quantification of histone methylation patterns have become pivotal in studying epigenetic regulation of genes, as well as inhibitor discovery.
Histone methylation is the modification of certain amino acids in a histone protein by the addition of methyl groups. Methylation and demethylation of histones turn genes on and off in DNA. Quantifying histone methylation is particularly useful for studying gene expression patterns.
Histone methyltransferases (HMTs) are enzymes that catalyze the transfer of methyl groups to histone proteins, and control or regulate DNA methylation through chromatin-dependent transcription repression or activation. Histone methylation serves in both epigenetic gene activation and silencing, thereby making it important to measure the activity or inhibition of HMTs.
Histone demethylation is the removal of methyl groups in modified histone proteins via histone demethylases. The discovery of histone demethylases demonstrates that histone methylation is not a permanent modification, but rather a more dynamic process. Specific demethylases are found to be involved in some pathological processes such as cancer progression, making it necessary to better understand the activity or inhibition of histone demethylases.