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General transcription factors (GTFs), also known as basal transcriptional factors, are a class of protein transcription factors that bind to specific sites (promoter) on DNA to activate transcription of genetic information from DNA to messenger RNA. GTFs, RNA polymerase, and the mediator multiple protein complex constitute the basic transcriptional apparatus that bind to the promoter, then start transcription. GTFs are also intimately involved in the process of gene regulation, and most are required for life. A transcription factor is a protein that binds to specific DNA sequences (enhancer or promoter), alone or with other proteins in a complex to control the rate of transcription of genetic information from DNA to messenger RNA, by promoting as an activator, or blocking as a repressor the recruitment of RNA polymerase.〔Nikolov DB, Burley SK (1997). "RNA polymerase II transcription initiation: A structural view". ''Proc. Natl. Acad. Sci. U.S.A.'' 94 (1): 15–22.Bibcode:1997PNAS...94...15N. doi:10.1073/pnas.94.1.15. PMC 33652.PMID 8990153.〕 As a class of protein transcription factors, General transcription factors bind to promoter on DNA sequence along or form a large transcription preinitiation complex to only activate transcription. General transcription factors are necessary for transcription to occur.〔Robert O. J. Weinzierl (1999). ''Mechanisms of Gene Expression: Structure, Function and Evolution of the Basal Transcriptional Machinery''. World Scientific Publishing Company. ISBN 1-86094-126-5.〕 == Types == In bacteria, transcription initiation requires an RNA polymerase and a single GTF: sigma factor. In archaea and eukaryotes, transcription initiation requires an RNA polymerase and a set of multiple GTFs form a transcription preinitiation complex. The Transcription initiation by eukaryotic RNA polymerase II involves the following GTFs: * TFIIA * TFIIB * TFIID * TFIIE * TFIIF * TFIIH 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「general transcription factor」の詳細全文を読む スポンサード リンク
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