The RNA polymerase I transcription factor, upstream binding factor, interacts directly with the TATA box-binding protein
Howard Hughes Medical Institute, Program in Molecular Medicine
Amino Acid Sequence; Cell Nucleus; Chromatography, Affinity; Chromatography, Ion Exchange; DNA-Binding Proteins; Electrophoresis, Polyacrylamide Gel; Hela Cells; Humans; Models, Structural; Molecular Sequence Data; Molecular Weight; Peptide Fragments; *Pol1 Transcription Initiation Complex Proteins; Promoter Regions (Genetics); RNA Polymerase I; TATA Box; TATA-Box Binding Protein; Transcription Factors; Transcription, Genetic
Life Sciences | Medicine and Health Sciences
The accurate transcription of human rRNA genes by RNA polymerase I requires two transcription factors, upstream binding factor (UBF) and promoter selectivity factor (SL1). Human SL1 (hSL1) is a multisubunit complex, one of whose components is TATA box-binding protein (TBP). hSL1 binds to the core region of the rRNA promoter, but does so inefficiently in the absence of human UBF (hUBF). hUBF interacts with the upstream control element of the rRNA promoter and facilitates binding of hSL1. The molecular basis by which hUBF increases binding of hSL1 remains to be elucidated. In this report, we use an immobilized protein binding assay to identify and purify a 95-kDa TBP-binding polypeptide. Microsequence analysis reveals that the 95-kDa TBP-binding protein is hUBF. We show that hUBF is stably associated with TBP and is present in large TBP-containing complexes. Our results indicate that the cooperative binding of hUBF and hSL1 on the rRNA promoter is mediated by direct interaction between hUBF and TBP. We also provide evidence that hUBF associates with TFIID, a TBP-containing RNA polymerase II transcription factor.
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Citation: J Biol Chem. 1994 Dec 2;269(48):30140-6.
The Journal of biological chemistry
Kwon, Hyockman and Green, Michael R., "The RNA polymerase I transcription factor, upstream binding factor, interacts directly with the TATA box-binding protein" (1994). Open Access Articles. 814.