Description
SETDB1 (SET Domain, Bifurcated 1) is a histone methyltransferase that methylates histone H3 at lysine 9. H3K9 methylation is associated with transcriptional repression and gene silencing through recruitment of HP1 proteins to methylated histones. H3K9 trimethylation is coordinated with DNA methylation, most likely through formation of a complex with MBD1 and ATF7IP that leads to transcriptional repression. SETDB1 activity is dependent on MBD1 and is heritably maintained through DNA replication by being recruited by CAF-1. SETDB1 is targeted to histone H3 by TRIM28, a factor recruited by KRAB zinc-finger proteins. Aberrant SETDB1 function is associated with the pathogenesis of Huntington Disease