Diverse factors are involved in maintaining X chromosome inactivation.

ABSTRACT: X chromosome inactivation (XCI) is the most dramatic example of epigenetic silencing in eukaryotes. Once established, the inactivated X chromosome (Xi) remains silenced throughout subsequent cell divisions. Though the initiation of XCI has been studied extensively, the protein factors involved in Xi silencing and maintenance are largely unknown. Here we report the discovery of a diverse set of 32 proteins involved in maintenance of Xi silencing through a genome-wide RNAi screen. In addition, we describe the mechanistic roles of two proteins--origin recognition complex 2 (Orc2) and heterochromatin protein 1 (HP1α)--in Xi silencing. Immunofluorescence studies indicate that Orc2 and HP1α localize on Xi in mouse cells. Depletion of Orc2 by shRNA leads to the loss of both Orc2 and HP1α localiza

SUBMITTER: Chan KM 

PROVIDER: S-EPMC3189073 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature