Open AccessProperties of Ets-1 Binding to Chromatin and Its Effect on Platelet Factor 4 Gene Expression
Author(s) -
Jun Lü,
Michael J. Pazin,
Katya Ravid
Publication year - 2004
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.24.1.428-441.2004
Subject(s) - biology , chromatin , promoter , chromatin immunoprecipitation , chia pet , transcription factor , microbiology and biotechnology , chip sequencing , binding site , transactivation , dna binding protein , gene expression , dna , gene , chromatin remodeling , genetics
Ets-1 is important for transcriptional regulation in several hematopoietic lineages, including megakaryocytes. Some transcription factors bind to naked DNA and chromatin with different affinities, while others do not. In the present study we used the megakaryocyte-specific promoters platelet factor 4 (PF4), and glycoprotein IIb (GPIIb) as model systems to explore the properties of Ets-1 binding to chromatin. Chromatin immunoprecipitation assays indicated that Ets-1 binds to proximal regions in the PF4 and GPIIb promoters in vivo. In vitro and in vivo experiments showed that Ets-1 binding to chromatin on lineage-specific promoters does not require lineage-specific factors. Moreover, this binding shows the same order of affinity as the binding to naked DNA and does not require ATP-dependent or Sarkosyl-sensitive factors. The effect of Ets-1 binding on promoter activity was examined using the PF4 promoter as a model. We identified a novel Ets-1 site (at -50), and a novel Sarkosyl-sensitive DNase I-hypersensitive site generated by Ets-1 binding to chromatin, which significantly affect PF4 promoter activity. Taken together, our results suggest a model by which Ets-1 binds to chromatin without the need for lineage-specific accessory factors, and Ets-1 binding induces changes in chromatin and affects transactivation, which are essential for PF4 promoter activation.