Coregulator-dependent facilitation of chromatin occupancy by GATA-1.
Coregulator recruitment by DNA-bound factors results in chromatin modification and protein-protein interactions, which regulate transcription. However, the mechanism by which the Friend of GATA (FOG) coregulator mediates GATA factor-dependent transcription is unknown. We showed previously that GATA-1 replaces GATA-2 at an upstream region of the GATA-2 locus, and that this GATA switch represses GATA-2. Genetic complementation analysis in FOG-1-null hematopoietic precursors revealed that FOG-1 is not required for establishment or maintenance of the active GATA-2 domain, but is critical for the GATA switch. Analysis of GATA factor binding to additional loci also revealed FOG-1-dependent GATA switches. Thus, FOG-1 facilitates chromatin occupancy by GATA-1 at sites bound by GATA-2. We propose that FOG-1 is a prototype of a new class of coregulators termed chromatin occupancy facilitators, which confer coregulation in certain contexts via enhancing trans-acting factor binding to chromatin in vivo.
Pal
Saumen
S
Department of Pharmacology, University of Wisconsin Medical School, 1300 University Avenue, 383 Medical Sciences Center, Madison, WI 53706, USA.
Cantor
Alan B
AB
Johnson
Kirby D
KD
Moran
Tyler B
TB
Boyer
Meghan E
ME
Orkin
Stuart H
SH
Bresnick
Emery H
EH
D002352:Carrier Proteins / Q000502:physiology; D002461:Cell Line, Transformed; D002843:Chromatin / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D050981:Erythroid-Specific DNA-Binding Factors; D050989:GATA2 Transcription Factor; D009687:Nuclear Proteins / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic
D002352:Carrier Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050989:GATA2 Transcription Factor; D009687:Nuclear Proteins; D014157:Transcription Factors; C498432:ZFPM1 protein, human