Protein Domain : N-lysine methyltransferase KMT5A-like IPR016858

Type	Family
Description	This entry includes a group of animal proteins that belong to the class V-like SAM-binding methyltransferase superfamily and contain the SET domain usually flanked by other domains forming the so-called pre- and post-SET regions. The enzymes belonging to this class all N-methylate lysine in proteins. Most of them are histone methyltransferases (), including human N-lysine methyltransferase KMT5A (also known as PR-Set7), which is a nucleosomal histone-lysine N-methyltransferase that specifically monomethylates 'Lys-20' of histone H4 (H4K20me1). It plays a central role in the silencing of euchromatic genes [ , , , ].Methyltransferases (EC 2.1.1.-) constitute an important class of enzymes present in every life form. They transfer a methyl group most frequently fromS-adenosyl L-methionine (SAM or AdoMet) to a nucleophilic acceptor such as nitrogen, oxygen, sulfur or carbon leading to S-adenosyl-L-homocysteine(AdoHcy) and a methylated molecule. The substrates that are methylated by these enzymes cover virtually every kind of biomolecules ranging from smallmolecules, to lipids, proteins and nucleic acids. Methyltransferases are therefore involved in many essential cellular processes includingbiosynthesis, signal transduction, protein repair, chromatin regulation and gene silencing [, , ]. More than 230 different enzymatic reactions ofmethyltransferases have been described so far, of which more than 220 use SAM as the methyl donor [E1]. A review published in 2003 [ ] divides allmethyltransferases into 5 classes based on the structure of their catalytic domain (fold):class I: Rossmann-like α/β class II: TIM beta/α-barrel α/β class III: tetrapyrrole methylase α/βclass IV: SPOUT α/β class V: SET domain all βA more recent paper [ ] based on a study of the Saccharomyces cerevisiae methyltransferome argues for four more folds:class VI: transmembrane all α class VII: DNA/RNA-binding 3-helical bundle all α class VIII: SSo0622-like α+β class IX: thymidylate synthetase α+β
Short Name	KMT5A-like