Heterochromatin protein 1 modifies mammalian PEV in a dose- and chromosomal-context-dependent manner.

摘要: Locus control regions (LCRs) are gene regulatory elements in mammals that can overcome the highly repressive effects normally associated with heterochromatic transgene locations (for example centromere) mice1,2,3. Deletion of essential LCR sequences renders cognate susceptible to this form repression, so a proportion cells from transgenic mice would express silenced—a phenomenon known as position effect variegation4,5,6 (PEV). We show here PEV also occur when is non-centromeric and extent variegation be developmentally regulated. Furthermore, by overexpressing mammalian homologue (M31) Drosophila melanogaster heterochromatin protein 1 (HP1; refs 7,8) mouse lines exhibit PEV, it possible modify silence dose-dependent manner. Thus, we M31 overexpression have two contrasting which dependent on chromosomal context: (i) enhanced those centromeric or pericentromeric locations; (ii) suppressed was non-centromeric. Our results indicate components modifiers may chromosomal-context-dependent role silencing activation decisions mammals.