YY1 associates with the macrosatellite DXZ4 on the inactive X chromosome and binds with CTCF to a hypomethylated form in some male carcinomas.

ABSTRACT: DXZ4 is an X-linked macrosatellite composed of 12-100 tandemly arranged 3-kb repeat units. In females, it adopts opposite chromatin arrangements at the two alleles in response to X-chromosome inactivation. In males and on the active X chromosome, it is packaged into heterochromatin, but on the inactive X chromosome (Xi), it adopts a euchromatic conformation bound by CTCF. Here we report that the ubiquitous transcription factor YY1 associates with the euchromatic form of DXZ4 on the Xi. The binding of YY1 close to CTCF is reminiscent of that at other epigenetically regulated sequences, including sites of genomic imprinting, and at the X-inactivation centre, suggesting a common mode of action in this arrangement. As with CTCF, binding of YY1 to DXZ4 in vitro is not blocked by CpG methylation

SUBMITTER: Moseley SC 

PROVIDER: S-EPMC3287207 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature