Transcription Factor II F
Encyclopedia
Transcription factor II F (TFIIF) is one of several general transcription factor
s that make up the RNA polymerase II
preinitiation complex
.
Transcription Factor II F is encoded by the , , and genes. DNA
is thought to be wrapped one complete turn around the preinitiation complex and it is TFIIF that helps keep this tight wrapping. In the process, the torsional strain on the DNA may aid in DNA melting at the promoter, forming the transcription bubble
. Of all the general transcription factors, TFIIF is the most similar to bacterial sigma factor
.
General transcription factor
General transcription factors or basal transcription factors are protein transcription factors that have been shown to be important in the transcription of class II genes to mRNA templates...
s that make up the RNA polymerase II
RNA polymerase II
RNA polymerase II is an enzyme found in eukaryotic cells. It catalyzes the transcription of DNA to synthesize precursors of mRNA and most snRNA and microRNA. A 550 kDa complex of 12 subunits, RNAP II is the most studied type of RNA polymerase...
preinitiation complex
Preinitiation complex
The preinitiation complex is a large complex of proteins that is necessary for the transcription of protein-coding genes in eukaryotes...
.
Transcription Factor II F is encoded by the , , and genes. DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
is thought to be wrapped one complete turn around the preinitiation complex and it is TFIIF that helps keep this tight wrapping. In the process, the torsional strain on the DNA may aid in DNA melting at the promoter, forming the transcription bubble
Transcription bubble
A transcription bubble is a molecular structure that occurs during the transcription or replication of DNA when DNA helicase and DNA topoisomerase "unzip" the DNA double strand. DNA polymerase or RNA polymerase may then bind to the exposed DNA and begin synthesizing a new strand of DNA or RNA...
. Of all the general transcription factors, TFIIF is the most similar to bacterial sigma factor
Sigma factor
A sigma factor is a bacterial transcription initiation factor that enables specific binding of RNA polymerase to gene promoters. Different sigma factors are activated in response to different environmental conditions...
.