| HP1 is a well known conserved protein involved in heterochromatin formation and gene silencing in different species including humans1-4. A general model has been proposed for heterochromatin formation and epigenetic gene silencing in different species that implies an essential role for HP1. According to the model, histone methyltransferase enzymes (HMTases) methylate the histone H3 at lysine 9 (H3-MeK9), creating selective binding sites for itself and the chromodomain of HP15. This complex is thought to form a higher order chromatin state that represses gene activity. It has also been found that HP1 plays a role in telomere capping6. Surprisingly, recent data have suggested an association of HP1 in gene activity7-10 but the nature of this interaction is... |
