Abstract
Over 400 Krüppel-associated box zinc finger proteins (KRAB-ZFPs) are encoded in mammalian genomes. While KRAB-ZFPs strongly repress transcription in vitro, little is known about their biological function or gene targets in vivo. Regulator of sex limitation 1 (Rsl1), one of the first KRAB-Zfp genes assigned a physiological role, accentuates sex-biased liver gene expression, most dramatically for mouse sex-limited protein (Slp), which provides an in vivo reporter of KRAB-ZFP function. Slp is induced in males in the liver and kidney by growth hormone (GH) and androgen, respectively. In the liver but not kidney, the Rsl1 genotype correlates with methylation of a CpG dinucleotide in the Slp promoter that is demethylated at puberty. RSL1 binds 2 kb upstream of the Slp promoter, both in vitro and in vivo, within an enhancer containing response elements for STAT5b. Chromatin immunoprecipitation (ChIP) assays demonstrate that RSL1 recruits KAP1/TRIM28, the corepressor for KRAB action in vitro, to this enhancer. Slp induction requires rapid cycling of STAT5b in chromatin. Remarkably, RSL1 simultaneously binds adjacent to STAT5b with a reciprocal binding pattern that limits hormonal response. These experiments demonstrate a surprisingly dynamic interplay between a hormonal activator, STAT5b, and a KRAB-ZFP repressor and provide unique insights into KRAB-ZFP epigenetic mechanisms.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.