CBX1 is the component of heterochromatin. CBX1 recognizes and binds histone H3 tails methylated at 'Lys-9', leading to epigenetic repression. CBX1 interaction with lamin B receptor (LBR) can contribute to the association of the heterochromatin with the inner nuclear membrane.Heterochromatin protein-1 (HP1) is localized at heterochromatin sites, where it mediates gene silencing.[supplied by OMIM].