ADDz domain found in DNA (cytosine-5) methyltransferases (C5-MTases) 3 like (Dnmt3l)
Dnmt3l is a regulator of DNA methylation, which acts by recognizing unmethylated histone H3 tails and interacting with Dnmt3a to stimulate its de novo DNA methylation activity. The ADDz_Dnmt3l domain is located in the C-terminal region of Dnmt3l that otherwise lacks some residues required for DNA methyltransferase activity. DNA methylation is an important epigenetic mechanism involved in diverse biological processes such as embryonic development, gene expression, and genomic imprinting. Dnmt3l is also associating with HDAC1 and acts as a transcriptional repressor. The ADDz_Dnmt3l domain is a PHD-like zinc finger motif that contains two parts, a C2-C2 and a PHD-like zinc finger. PHD zinc finger domains have been identified in more than 40 proteins that are mainly involved in chromatin mediated transcriptional control; the classical PHD zinc finger has a C4-H-C3 motif that spans about 50-80 amino acids. In ADDz, the conserved histidine residue of the PHD finger is replaced by a cysteine, and an additional zinc finger C2-C2 like motif is located about twenty residues upstream of the C4-C-C3 motif.