title: GATA-1 transactivates the WT1 hematopoietic specific enhancer.
abstract: The Wilms' tumor gene, WT1, is believed to play a role in hematopoiesis as it is expressed in the spleen and in immature leukemias in addition to the developing genitourinary system. WT1 is down-regulated in differentiated leukemia cells both in vivo and in vitro and is up-regulated in fetal spleen and immature leukemia cells. The modulation of WT1 expression was examined in many cell types, and a hematopoietic-specific enhancer element has been identified. Here we describe the transcriptional response of this enhancer to hematopoietic-specific transcription factors. We found co-expression of WT1 and GATA-1 mRNA in K562 cells and in mouse spleen, suggesting potential interactions between these two transcription factors. We find that the activity of the 3' WT1 enhancer is positively correlated with the expression of GATA-1. Gel shift competition experiments and transactivation studies revealed that this functional activity is mediated via binding at a GATA-binding site in the WT1 enhancer. The transactivation of the WT1 enhancer by GATA-1 implies that GATA-1 plays a role in the regulation of WT1 during hematopoiesis.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Texas M.D. Anderson Cancer Center, Houston 77030.
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.forename: G C
authors.initials: GC
authors.lastname: Fraizer
authors.forename: G F
authors.initials: GF
authors.lastname: Saunders
mesh_terms: D001483:Base Sequence; D006528:Carcinoma, Hepatocellular; D002454:Cell Differentiation; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004742:Enhancer Elements, Genetic; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D015972:Gene Expression Regulation, Neoplastic; D016162:Genes, Wilms Tumor; D006367:HeLa Cells; D006410:Hematopoiesis; D006801:Humans; D007668:Kidney; D007938:Leukemia; D008113:Liver Neoplasms; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D016335:Zinc Fingers
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; D014157:Transcription Factors