Oligonucleotides and sequence alignment. (A)
Oligonucleotides used in previous crystal structures (14, 15, 20). The
abbreviations used are as follows: h, human; at, Arabidopsis
thaliana; pw, Pyrococcus woesei;
TF(II)Bc, C-terminal core of TF(II)B; and ad MLPromoter,
adenovirus major late promoter. (B) Comparison of the
archaeal BRE consensus (18) with the oligonucleotide used in the
current TBP/TFB/DNA structure. (C)
clustalw (21) alignment of the C-terminal cores of TFB and
TFIIB. The TFBs listed (and their database accession numbers) are from
Pyrococcus woesei (P29095), Archaeoglobus
fulgidus (AE001014), Methanococcus jannaschii
(AAB98771), Methanobacterium thermoautotrophicum
(AE000864), and Sulfolobus shibatae (AAA81380). The
metazoan TFIIBs listed are from Drosophila melanogaster
(AAA79093), Homo sapiens (AAA61149), Rattus
norvegicus (CAA46766), and Xenopus
laevis (CAA44668). The plant TFIIBs listed are from
Arabidopsis thaliana (AAC35529) and Glycine
max (AAB09756). The fungal TFIIBs listed are from
Saccharomyces cerevisiae (AAB68135) and
Kluyveromyces lactis (AAA35258). Conservation is
indicated as follows: white text on a black background, completely
conserved; white text on a dark gray background, conserved; black text
on a light gray background, similar; black text on a white background,
unconserved; black text on a light green background, conserved in all
metazoan and archaeal proteins and contacts BRE; black text on a light
yellow background, similar and contacts BRE; black text on a light blue
background, unconserved and contacts BRE; and black text on a magenta
background, contacts the DNA downstream of the TATA box. Helices are
indicated as green boxes above the sequence alignment, labeled using
the nomenclature of Nikolov et al. (9). The two helices
of the helix–turn–helix (HTH) motif are colored pink. Residues
explicitly mentioned in the text are indicated by numbers underneath
the alignment. C was made with boxshade
[maintained by K. Hofmann (khofmann@isrec-sun1.unil.ch) and M.
D. Baron (michael.baron@bbsrc.ac.uk)].