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]
Binding
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 archaeonPyrococcus 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]
^In nucleic acid notation for DNA, R (puRine) stands for A/G (adenine or guanine, which are both purines); S (Strong) stands for C/G (cytosine or guanine, which base-pair to form three hydrogen bonds); K (Keto) stands for G/T; D (not C) stands for A/T/G.
