The KRAB zinc finger protein RSL1 regulates sex- and tissue-specific promoter methylation and dynamic hormone-responsive chromatin configuration.
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.
Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA.
Christopher J
CJ
Krebs
David C
DC
Schultz
Diane M
DM
Robins
D000818:Animals; D002843:Chromatin / Q000378:metabolism*; D003181:Complement C4 / Q000235:genetics; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012097:Repressor Proteins / Q000378:metabolism*; D020218:Response Elements; D050799:STAT5 Transcription Factor / Q000096:biosynthesis / Q000378:metabolism*; D000076183:Tripartite Motif-Containing Protein 28
C018386:C4a protein, mouse; D002843:Chromatin; D003181:Complement C4; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; C550540:Rsl1 protein, mouse; D050799:STAT5 Transcription Factor; C494096:Stat5b protein, mouse; C103190:Trim28 protein, mouse; D000076183:Tripartite Motif-Containing Protein 28