Histone proteins HKMTs

Histone lysine (K) methyltransferase (HKMTs) may lead to mono, di- and trimethy-lation of the E-amino group and the extent of modification at a specific site controls the recruitment of the effector proteins. Two unequally populated folds are presently known the SET domain-containing family and the Dotl family (for a recent review, see Ref. [70])... 

Dotl proteins and S ET H KMTs illustrate how methyl transfer to a protein Lys side-chain can be done with different structural scaffolding and unrelated local active site spatial arrangements. To date, Dotl proteins are the only nonSET HKMTs and further work and structures are needed to understand the mechanism of methylation of Lys-79, a histone core residue. 

Lysine 9 of histone H3 is the target of many SET-domain-containing enzymes (Fig. 2). Most of the HKMTs that methylate this residue belong to the Su(var)3-9 family. In Drosophila and humans, methylation of this lysine provides a binding site for the chromo domain of heterochromatin protein 1 (HP1 Aagaard et al., 2000 Loyola et al., 2001). Work done in Drosophila has demonstrated that the interaction of HP1 and methylated... 

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