DNA (cytosine-5)-methyltransferase 3B, ADD domain (IPR030488)
Short name: DNMT3B_ADD
Overlapping homologous superfamilies
- Zinc finger, FYVE/PHD-type (IPR011011)
- ADD domain (IPR025766)
- DNA (cytosine-5)-methyltransferase 3B, ADD domain (IPR030488)
This entry represents the ADD domain of DNMT3B. The ADD domain is composed of three clearly distinguishable modules that pack together through extensive hydrophobic interactions to form a single globular domain. Packed against this GATA-like finger is a second subdomain, which binds two zinc ions and closely resembles the structure reported for several PHD fingers. Finally, there is a long C-terminal alpha-helix that runs out from the PHD finger and makes extensive hydrophobic contacts with the N- terminal GATA finger, bringing the N- and C-termini of the ADD domain close together. This combination of fused GATA-like and PHD fingers within a single domain is thus far unique [PMID: 17609377, PMID: 19834512].
In mammals, DNA methylation patterns are thought to be established during embryonic development by de novo DNA methyltransferases 3A and 3B (DNMT3A/3B) [PMID: 10555141]. DNMT3A/3B work synergistically to propagate methylation patterns with DNMT3B stimulating DNMT3A activity by promoting its association with nucleosomes [PMID: 21304883]. Many DNMT3B isoforms from alternative splicing have been described, among which DNMT3B3 stimulates the basal activity of DNMT3 enzymes, but partially inhibits the stimulatory effect of DNMT3L, whereas DNMT3B4 significantly impairs de novo methylation [PMID: 25198254, PMID: 23894490]. DNMT3B is involved in development and is associated with several diseases, including cancers [PMID: 25198254].
- cd11728 (ADDz_Dnmt3b)