Human general transcription factor TFIIA: characterization of a cDNA encoding the small subunit and requirement for basal and activated transcription.
AUTOR(ES)
DeJong, J
RESUMO
The human general transcription factor TFIIA is one of several factors involved in specific transcription by RNA polymerase II, possibly by regulating the activity of the TATA-binding subunit (TBP) of TFIID. TFIIA purified from HeLa extracts consists of 35-, 19-, and 12-kDa subunits. Here we describe the isolation of a cDNA clone (hTFIIA gamma) encoding the 12-kDa subunit. Using expression constructs derived from hTFIIA gamma and TFIIA alpha/beta (which encodes a 55-kDa precursor to the alpha and beta subunits of natural TFIIA), we have constructed a synthetic TFIIA with a polypeptide composition similar to that of natural TFIIA. The recombinant complex supports the formation of a DNA-TBP-TFIIA complex and mediates both basal and Gal4-VP16-activated transcription by RNA polymerase II in TFIIA-depleted nuclear extracts. In contrast, TFIIA has no effect on tRNA and 5S RNA transcription by RNA polymerase III in this system. We also present evidence that both the p55 and p12 recombinant subunits interact with TBP and that the basic region of TBP is critical for the TFIIA-dependent function of TBP in nuclear extracts.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=42156Documentos Relacionados
- Analysis of the yeast transcription factor TFIIA: distinct functional regions and a polymerase II-specific role in basal and activated transcription.
- Molecular cloning of cDNA encoding the small subunit of Drosophila transcription initiation factor TFIIF.
- Isolation and characterization of a cDNA encoding Drosophila transcription factor TFIIB.
- Complete cDNA sequence encoding the B subunit of human factor XIII.
- Isolation and characterization of cDNA clones encoding human liver glutamate dehydrogenase: evidence for a small gene family.
