POZ domain transcription factor, FBI-1, represses transcription of ADH5/FDH by interacting with the zinc finger and interfering with DNA binding activity of Sp1.
The POZ domain is a protein-protein interaction motif that is found in many transcription factors, which are important for development, oncogenesis, apoptosis, and transcription repression. We cloned the POZ domain transcription factor, FBI-1, that recognizes the cis-element (bp -38 to -22) located just upstream of the core Sp1 binding sites (bp -22 to +22) of the ADH5/FDH minimal promoter (bp -38 to +61) in vitro and in vivo, as revealed by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. The ADH5/FDH minimal promoter is potently repressed by the FBI-1. Glutathione S-transferase fusion protein pull-down showed that the POZ domains of FBI-1, Plzf, and Bcl-6 directly interact with the zinc finger DNA binding domain of Sp1. DNase I footprinting assays showed that the interaction prevents binding of Sp1 to the GC boxes of the ADH5/FDH promoter. Gal4-POZ domain fusions targeted proximal to the GC boxes repress transcription of the Gal4 upstream activator sequence-Sp1-adenovirus major late promoter. Our data suggest that POZ domain represses transcription by interacting with Sp1 zinc fingers and by interfering with the DNA binding activity of Sp1.
Lee
Dong-Kee
DK
Department of Biochemistry and Molecular Biology, BK21 Project for Medical Sciences, Institute of Genetic Sciences, Yonsei University School of Medicine, 134 ShinChon-Dong, SeoDaeMoon-Ku, Seoul 120-752, Korea.
Suh
Dongchul
D
Edenberg
Howard J
HJ
Hur
Man-Wook
MW
D000445:Aldehyde Oxidoreductases / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003850:Deoxyribonuclease I / Q000378:metabolism; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D010957:Plasmids / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D014157:Transcription Factors; D014158:Transcription, Genetic; D016335:Zinc Fingers
D002843:Chromatin; D004268:DNA-Binding Proteins; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; C485514:ZBTB7A protein, human; C117093:Zbtb7a protein, mouse; D004247:DNA; D000445:Aldehyde Oxidoreductases; C087006:formaldehyde dehydrogenase, glutathione-independent; D003850:Deoxyribonuclease I