DNMT3a

By Emily Cartwright, PhD

By Jamshed Arslan, Pharm. D., PhD.

By Jamshed Arslan Pharm.D.

By Jamshed Arslan Pharm.D.

Epigenetics is the study of heritable change in gene activity despite alteration of the hosts DNA sequence.  Change in gene activity done independently of the DNA sequence is achieved by way of histone and DNA methylation.  Gene silencing in DNA methylation is carried out by DNA methyltransferases 1, 2 and 3a/b (DNMT1, DNMT2, DNMT3A/B). On a broad level, DNMTs methylate the fifth carbon of cytosine residues in DNA within CG dinucleotides.

DNA methylation plays a critical role the long-term silencing of transcription and is essential for processes such as embryonic development, germline differentiation, and tissue maturation.

DNA methyltransferases catalyze the transfer of the methyl group from S-andenosyl methionine (SAM) to DNA. Such methylation has wide ranging function in the cell, including organismal development and cell differentiation. In cancer, abnormal hypermethylation of gene promoter CpG islands can result in transcriptional silencing.