Pre-initiation
In eukaryotes, RNA polymerase, therefore, initiation of transcription requires the presence of the core promoter sequence DNA. Promoter is a region of DNA to stimulate transcription of eukaryotic found (to be abbreviated as TSS) bp -30, -75, -90 and transcription initiation site upstream. Primary sequence is a promoter within the promoter is essential for the initiation of transcription. RNA polymerase is able to bind to the core promoter in the presence of various factors specific to the transfer.
Most of the functionality of the core promoter in eukaryotes have found 25 to 30 base pairs upstream of the TSS is a short DNA sequence known as the box TATA. [QUOTE box TATA is a binding site for transcription factors known protein, a division of transcription factors another called (TFIID) transcription factor II D in sequence (TBP), a TATA binding Promoters basic some. TFIID, after binding to the TATA box by RNA polymerase combine around the TATA box of a series of steps to form a complex before and transcription factors of the two TBP, 5. Because it has two components having a helicase activity, in order to form an initial foam transcription, transcription factor, transcription factor II H is responsible for strand separation of opposing double-stranded DNA. However, the base L, or rate of transcription is driven by the pre-initiation complex alone. Other proteins known as repressor and activator with corepressors or coactivators all related, is responsible for the transfer speed adjusting.
Is substantially homologous to that of eukaryotic transcription to start before the archaea, but is far more complex. Assemble the TATA box binding site in full before initiation complex, but in archaea, the complex, by only (homolog of (TFIIB) transcription factor II B archaea and eukaryotes) TFB RNA polymerase II, and TBP is formed.
Migration feature before starting complex (PIC) to the open complex (yeast ortholog of mammalian XPB) subunit TFIIH SSL2 yeast RNA polymerase II (Pol II) and transcription factor TFIIE general. We form a heterodimer TFA1 (TFIIEα) WH connecting the Tfa2 and Pol II clamp which became one strand complex tandem WH domain bypass promoter DNA is open domain 3 TFIIE wing helix (WH) and (TFIIEβ) I show that. SSL2 is located under cover, to TFIIE near the promoter DNA. In contrast to previous proposals, comparing the model complex and open PIC, very DNA SSL2 suggesting that supplies the 15 base pairs in crevices Pol II, to facilitate the detection of the function as double-stranded DNA translocase are. Strand of DNA by SSL2 channel coupling, to develop an open state and the results of the DNA in combination with downstream of the fixed position of promoter DNA on the right side.
Type II topoisomerase catalyzes the re-connection path and DNA double-strand DNA breaks in order to make the topology change. There is considerable interest in elucidating the role of topoisomerase II, in particular, these proteins, is the target of anti-cancer drugs. Here, to find the role of topoisomerase IIα of RNA polymerase and increased I directed transcription of ribosomal RNA genes to drive the proliferation and cell growth, and in cancer cells. Topoisomerase IIα is a component of the RNA polymerase complex Iβ competent start, our data, interact with the RNA polymerase I-related transcription factor RRN3, which is directed to a polymerase to the promoter in connection SL1 initiation complex formed in advance directly I show that. The B cells, transcriptional activation, is reduced by a reduction in topoisomerase II inhibition or genetic recombination, which is reduced prior to forming the complex with associated double-stranded DNA breaks less transients in the promoter region of rDNA . To generate the rDNA promoter promotion topological modifications effective prior to the de novo transcription initiation complex formation, I topoisomerase IIα offer functionality RNA polymerase.
Assembly, disassembly, and functional properties of transcription before complex from human RNA polymerase I plays an important role in the regulation of rRNA gene expression (image) of (Pol I). For research and process factors employed, spray promoter template assay was developed to allow for isolating the nuclear extracts from the functional image to maintain the exact start of transcription. The pattern immunological factors bound These complexes, suggesting that include initiation of transcription, SL1, factors required for Pol I. (Figure) binding factor upstream In one round of transcription, we have to show that the remaining promoter binding and activists SL1. Furthermore, the promoter, UBF and SL1 were linked to retain the ability to function in initiation of transcription. SL1, has a central role in the stability of the PIC meeting and promoter DNA. Captured image of a template to be recycled efficiently yet be released from the transfer promoter PIC polymerase components immobilized to support transcription of multiple times by promoters “easy” carrying uterine blood flow and SL1 it is possible to resume. Polymerase organized clearance mainly synthesis rate of kinetic analysis of RNA initiation of transcription by Pol revealed that it is limiting the speed step after assembly and recruitment of Pol I. The PIC is Pol I-dependent transcription I It is determined by the rate at which it is listed as starts to escape promoters and transcription. The rate-limiting step of this Pol I transcription, it can be a major target in the regulation of gene expression of rRNA.