TATA binding proteins can recognize nontraditional DNA sequences.
We demonstrate an accurate, quantitative, and label-free optical technology for high-throughput studies of receptor-ligand interactions, and apply it to TATA binding protein (TBP) interactions with oligonucleotides. We present a simple method to prepare single-stranded and double-stranded DNA microarrays with comparable surface density, ensuring an accurate comparison of TBP activity with both types of DNA. In particular, we find that TBP binds tightly to single-stranded DNA, especially to stretches of polythymine (poly-T), as well as to the traditional TATA box. We further investigate the correlation of TBP activity with various lengths of DNA and find that the number of TBPs bound to DNA increases >7-fold as the oligomer length increases from 9 to 40. Finally, we perform a full human genome analysis and discover that 35.5% of human promoters have poly-T stretches. In summary, we report, for the first time to our knowledge, the activity of TBP with poly-T stretches by presenting an elegant stepwise analysis of multiple techniques: discovery by a novel quantitative detection of microarrays, confirmation by a traditional gel electrophoresis, and a full genome prediction with computational analyses.
Department of Biomedical Engineering, Boston University, Boston, MA, USA.
Sunmin
S
Ahn
Chia-Ling
CL
Huang
Emre
E
Ozkumur
Xirui
X
Zhang
Jyothsna
J
Chinnala
Ayca
A
Yalcin
Sabita
S
Bandyopadhyay
Shelly
S
Russek
M Selim
MS
Unlü
Charles
C
DeLisi
Rostem J
RJ
Irani
D001483:Base Sequence; D004247:DNA / Q000235:genetics* / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000235:genetics / Q000378:metabolism; D006801:Humans; D011071:Poly T / Q000378:metabolism; D011485:Protein Binding; D013379:Substrate Specificity; D016385:TATA Box; D035181:TATA-Box Binding Protein / Q000378:metabolism*
D004277:DNA, Single-Stranded; D035181:TATA-Box Binding Protein; D011071:Poly T; D004247:DNA