title: Distinct functions of dispersed GATA factor complexes at an endogenous gene locus.
abstract: The reciprocal expression of GATA-1 and GATA-2 during hematopoiesis is an important determinant of red blood cell development. Whereas Gata2 is preferentially transcribed early in hematopoiesis, elevated GATA-1 levels result in GATA-1 occupancy at sites upstream of the Gata2 locus and transcriptional repression. GATA-2 occupies these sites in the transcriptionally active locus, suggesting that a "GATA switch" abrogates GATA-2-mediated positive autoregulation. Chromatin immunoprecipitation (ChIP) coupled with genomic microarray analysis and quantitative ChIP analysis with GATA-1-null cells expressing an estrogen receptor ligand binding domain fusion to GATA-1 revealed additional GATA switches 77 kb upstream of Gata2 and within intron 4 at +9.5 kb. Despite indistinguishable GATA-1 occupancy at -77 kb and +9.5 kb versus other GATA switch sites, GATA-1 functioned uniquely at the different regions. GATA-1 induced histone deacetylation at and near Gata2 but not at the -77 kb region. The -77 kb region, which was DNase I hypersensitive in both active and inactive states, conferred equivalent enhancer activities in GATA-1- and GATA-2-expressing cells. By contrast, the +9.5 kb region exhibited considerably stronger enhancer activity in GATA-2- than in GATA-1-expressing cells, and other GATA switch sites were active only in GATA-1- or GATA-2-expressing cells. Chromosome conformation capture analysis demonstrated higher-order interactions between the -77 kb region and Gata2 in the active and repressed states. These results indicate that dispersed GATA factor complexes function via long-range chromatin interactions and qualitatively distinct activities to regulate Gata2 transcription.
authors.affiliation: University of Wisconsin Medical School, Department of Pharmacology, 1300 University Avenue, Madison, WI 53706, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Grass
authors.forename: Huie
authors.initials: H
authors.lastname: Jing
authors.forename: Shin-Il
authors.initials: SI
authors.lastname: Kim
authors.forename: Melissa L
authors.initials: ML
authors.lastname: Martowicz
authors.forename: Saumen
authors.initials: S
authors.lastname: Pal
authors.forename: Gerd A
authors.initials: GA
authors.lastname: Blobel
authors.forename: Emery H
authors.initials: EH
authors.lastname: Bresnick
mesh_terms: D000107:Acetylation; D000818:Animals; D020029:Base Pairing / Q000235:genetics; D001483:Base Sequence; D002843:Chromatin / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D017124:Conserved Sequence / Q000235:genetics; D003850:Deoxyribonuclease I / Q000378:metabolism; D004742:Enhancer Elements, Genetic / Q000235:genetics; D050982:GATA1 Transcription Factor / Q000235:genetics* / Q000378:metabolism*; D050989:GATA2 Transcription Factor / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011960:Receptors, Estrogen / Q000378:metabolism; D050880:p300-CBP Transcription Factors / Q000378:metabolism
chemical_list: D002843:Chromatin; D050982:GATA1 Transcription Factor; D050989:GATA2 Transcription Factor; D009687:Nuclear Proteins; D011960:Receptors, Estrogen; D050880:p300-CBP Transcription Factors; D003850:Deoxyribonuclease I