Suppressor Of Variegation 4-20 Homolog 1 (SUV420H1)

SUV420H1 encodes a protein that contains a SET domain. SET domains appear to be protein-protein interaction domains that mediate interactions with a family of proteins that display similarity with dual-specificity phosphatases (dsPTPases). The function of this gene has not been determined. Two alternatively spliced transcript variants have been found for this gene. The isolated SET domains of Suv420h1 and Suv420h2 showed strong methyltransferase activity toward nucleosomes, but only weak activity toward recombinant histone octamers, and none toward peptides and free histones. Western blot analysis using antibodies directed against mono-, di-, and trimethylated H4K20 showed that Suv420h1 and Suv420h2 products were enriched for trimethylated H4K20.