scholarly journals Multiple functional domains of human transcription factor IIB: distinct interactions with two general transcription factors and RNA polymerase II.

1993 ◽  
Vol 7 (6) ◽  
pp. 1021-1032 ◽  
Author(s):  
I Ha ◽  
S Roberts ◽  
E Maldonado ◽  
X Sun ◽  
L U Kim ◽  
...  
2008 ◽  
Vol 36 (4) ◽  
pp. 595-598 ◽  
Author(s):  
Laura M. Elsby ◽  
Stefan G.E. Roberts

Transcription by RNA polymerase II requires the assembly of the general transcription factors at the promoter to form a pre-initiation complex. The general transcription factor TF (transcription factor) IIB plays a central role in the assembly of the pre-initiation complex, providing a bridge between promoter-bound TFIID and RNA polymerase II/TFIIF. We have characterized a series of TFIIB mutants in their ability to support transcription and recruit RNA polymerase II to the promoter. Our analyses identify several residues within the TFIIB zinc ribbon that are required for RNA polymerase II assembly. Using the structural models of TFIIB, we describe the interface between the TFIIB zinc ribbon region and RNA polymerase II.


2004 ◽  
Vol 32 (6) ◽  
pp. 1098-1099 ◽  
Author(s):  
L.M. Elsby ◽  
S.G.E. Roberts

Transcription by RNA polymerase II requires the assembly of the general transcription factors at the promoter to form a preinitiaiton complex. TFIIB (transcription factor IIB) plays a central role in this process, mediating the recruitment of RNA polymerase II and positioning it over the transcription start site. The assembly of TFIIB at the promoter can be a limiting event and several activator proteins have been shown to target TFIIB recruitment in the process of transcriptional stimulation. TFIIB is composed of two domains that engage in an intramolecular interaction. Indeed, the conformation of TFIIB has been found to underpin the function of this general transcription factor. Here we discuss our current understanding of TFIIB conformation and its role in transcription control.


1999 ◽  
Vol 19 (11) ◽  
pp. 7377-7387 ◽  
Author(s):  
Delin Ren ◽  
Lei Lei ◽  
Zachary F. Burton

ABSTRACT Human transcription factor IIF (TFIIF) is an α2β2 heterotetramer of RNA polymerase II-associating 74 (RAP74) and RAP30 subunits. Mutagenic analysis shows that the N-terminal region of RAP74 between L155 (leucine at codon 155) and M177 is important for initiation. Mutants in this region have reduced activity in transcription, but none are inactive. Single amino acid substitutions at hydrophobic residues L155, W164, I176, and M177 have similar activity to RAP74(1–158), from which all but three amino acids of this region are deleted. Residual activity can be explained because each of these mutants forms a complex with RAP30 and recruits RNA polymerase II into the preinitiation complex. Mutants are defective for formation of the first phosphodiester bond from the adenovirus major late promoter but do not appear to have an additional significant defect in promoter escape. Negative DNA supercoiling partially compensates for the defects of TFIIF mutants in initiation, indicating that TFIIF may help to untwist the DNA helix for initiation.


1999 ◽  
Vol 19 (3) ◽  
pp. 2130-2141 ◽  
Author(s):  
T. C. Kuhlman ◽  
H. Cho ◽  
D. Reinberg ◽  
N. Hernandez

ABSTRACT RNA polymerase II transcribes the mRNA-encoding genes and the majority of the small nuclear RNA (snRNA) genes. The formation of a minimal functional transcription initiation complex on a TATA-box-containing mRNA promoter has been well characterized and involves the ordered assembly of a number of general transcription factors (GTFs), all of which have been either cloned or purified to near homogeneity. In the human RNA polymerase II snRNA promoters, a single element, the proximal sequence element (PSE), is sufficient to direct basal levels of transcription in vitro. The PSE is recognized by the basal transcription complex SNAPc. SNAPc, which is not required for transcription from mRNA-type RNA polymerase II promoters such as the adenovirus type 2 major late (Ad2ML) promoter, is thought to recruit TATA binding protein (TBP) and nucleate the assembly of the snRNA transcription initiation complex, but little is known about which GTFs other than TBP are required. Here we show that the GTFs IIA, IIB, IIF, and IIE are required for efficient RNA polymerase II transcription from snRNA promoters. Thus, although the factors that recognize the core elements of RNA polymerase II mRNA and snRNA-type promoters differ, they mediate the recruitment of many common GTFs.


1998 ◽  
Vol 63 (0) ◽  
pp. 83-105 ◽  
Author(s):  
D. REINBERG ◽  
G. ORPHANIDES ◽  
R. EBRIGHT ◽  
S. AKOULITCHEV ◽  
J. CARCAMO ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document