Preinitiation complex: Difference between revisions
Created page with 'The preinitiation complex (PIC) is a complex of proteins that is formed in eukaryotic cells previous initiation of transcription. It consists of RNA polymerase …' |
No edit summary |
||
| Line 1: | Line 1: | ||
The preinitiation complex (PIC) is a complex of proteins that is formed in eukaryotic cells previous initiation of [[Transcription|transcription]]. It consists of RNA polymerase II and a series of [[Trancription factors|transcription factors]] (TF), which have different functions and are RNA polymerase specific. <br>The main function of the preinitiation complex is to recruit [[Rna polymerase|RNA polymerase]], that is necessary to undergo transcription, and to allow binding of this enzyme with basal promoter region of DNA. | The preinitiation complex (PIC) is a complex of proteins that is formed in [[Eukaryotic cells|eukaryotic cells]] previous initiation of [[Transcription|transcription]]. It consists of [[RNA polymerase II|RNA polymerase II]] and a series of [[Trancription factors|transcription factors]] (TF), which have different functions and are [[RNA polymerase|RNA polymerase]] specific. <br>The main function of the preinitiation complex is to recruit [[Rna polymerase|RNA polymerase]], that is necessary to undergo transcription, and to allow binding of this [[enzyme|enzyme]] with basal promoter region of [[DNA|DNA]]. | ||
There are six types of transcription factors that participate in the formation of the PIC: [[TFIIA|TFIIA]], [[TFIIB|TFIIB]], [[TFIID|TFIID]], [[TFIIE|TFIIE]], [[TFIIF|TFIIF]], [[TFIIH|TFIIH]].<br>[[TFIID|TFIID]] is the first one to bind to the [[Tata box|TATA box]] basal promoter region of [[DNA|DNA]] and consists of a [[TATA binding protein|TATA binding protein]] (TBP) subunit and [[TBP-associated factors|TBP-associated factors]] (TAFs) <ref>B.Turner(2001), Chromatin and gene regulation: machanisms in epigenetics (1st ed), Oxford: Blackwell Science</ref>. | |||
[[TFIIB|TFIIB]] is the [[Transcription factor|transcription factor]] that recruits [[RNA pol II|RNA pol II]] while [[TFIIH|TFIIH]] has an helicase activity and unwinds the [[DNA|DNA]] strand before transcription starts. | |||
< | === References:<br> === | ||
<references /><br> | |||
Revision as of 19:09, 23 November 2010
The preinitiation complex (PIC) is a complex of proteins that is formed in eukaryotic cells previous initiation of transcription. It consists of RNA polymerase II and a series of transcription factors (TF), which have different functions and are RNA polymerase specific.
The main function of the preinitiation complex is to recruit RNA polymerase, that is necessary to undergo transcription, and to allow binding of this enzyme with basal promoter region of DNA.
There are six types of transcription factors that participate in the formation of the PIC: TFIIA, TFIIB, TFIID, TFIIE, TFIIF, TFIIH.
TFIID is the first one to bind to the TATA box basal promoter region of DNA and consists of a TATA binding protein (TBP) subunit and TBP-associated factors (TAFs) [1].
TFIIB is the transcription factor that recruits RNA pol II while TFIIH has an helicase activity and unwinds the DNA strand before transcription starts.
References:
- ↑ B.Turner(2001), Chromatin and gene regulation: machanisms in epigenetics (1st ed), Oxford: Blackwell Science