The B recognition element (BRE) is a DNA sequence found in the promoter region of most[clarification needed] genes in eukaryotes and Archaea.[1][2] The BRE is a cis-regulatory element that is found immediately near TATA box, and consists of 7 nucleotides. There are two sets of BREs: one (BREu) found immediately upstream of the TATA box, with the consensus SSRCGCC; the other (BREd) found around 7 nucleotides downstream, with the consensus RTDKKKK.[a][3][4]
The BREu was discovered in 1998 by Richard Ebright and co-workers.[1] The BREd was named in 2005 by Deng and Roberts;[5] such a downstream recognition was reported earlier in 2000 in Tsai and Sigler's crystal structure.[6]
The transcription factor II B (TFIIB) recognizes either BRE and binds to it. Both BREs work in conjunction with the TATA box (and TATA box binding protein), and have various effects on levels of transcription.[4]
TFIIB uses the cyclin-like repeats to recognize DNA. The C-terminal alpha helices of TFIIB intercalate with the major groove of the DNA at the BREu. The N-terminal helices bind to the minor groove at BREd. TFIIB is one part of the preinitiation complex that helps RNA polymerase II bind to the DNA.[6]
In addition to the human TFIIB-BRE structure, structures from many other organisms have been solved. Among those are transcription factor B (TFB) from the archaeon Pyrococcus woesei which presents an inverted orientation[7] and a TFIIB from the parasite Trypanosoma brucei which despite some specific insertions show a similar fold.[8]
|
| |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Transcriptional regulation |
| ||||||||||||
| Promotion |
| ||||||||||||
| Initiation |
| ||||||||||||
| Elongation |
| ||||||||||||
| Termination (bacterial, eukaryotic) |
| ||||||||||||
 | This genetics article is a stub. You can help Wikipedia by expanding it. |
