DNMT3B

DNMT3B, also known as DNA methyltransferase 3β, has alternative names including ICF and ICF1. DNMT3B is a DNA methyltransferase that is primarily expressed and active during the early stages of embryonic development. It is responsible for de novo methylation, which involves adding a methyl group to the fifth carbon atom of cytosine in the DNA sequence. DNMT3B transfers the methyl group from S-adenosylmethionine (SAM) to cytosine, a process crucial for gene expression regulation, embryonic development, cell differentiation, genomic imprinting, transposon silencing, and X chromosome inactivation. DNMT3B plays a significant role in maintaining DNA methylation patterns, gene expression regulation, and chromatin structure. Abnormal expression or dysfunction of DNMT3B is associated with various diseases, including immunodeficiency, centromere instability, and facial abnormalities syndrome (ICF syndrome), as well as the occurrence and progression of tumors.