Nanoproe Based TATA-Binding-Protein Sensing And Research On DNA-protein Interaction

Stochastically opening and closing of the biological channels and pores on cell membrane is essential for many kinds of fundamental life functions. Recent advances in molecular science and nanotechnology offer unprecedented opportunities to explore this intrigued field. Endowed with chemical selectivity by integration with nucleic-acid-based sensing elements, bio-mimetic nanopore-system becomes an efficient platform to realize the DNA-based nanopore sensing and gating. Bio-mimetic nanopore-systems not only can enable us to analyze protein, DNA and other biological small target molecules, but also can be used as a biological mimic device. The main content of the dissertation are as follows:1. Monitoring transcription factor(TF) expression levels provides an important assessment of the state of cell populations. However, there is still a huge gap between the clinical requirement and reliable detection limit. Combined with a strain of DNA probe,which contain an efficient TATA-binding site,the nanopore system can be used as a highly sensitive and selective TATA-Binding protein(TBP) sensing platform. We achieved a reliable detection limit of 1 pM for target transcription factor(TBP).2. The motions and the bindings between a certain protein(for instance, transcription factors) and its specific DNA strand are completely dominated by the surrounding other proteins and DNA strands in a very limited space. By successively designing 1 strain of DNA detection probe along with 6 different DNA-probes, we propose a new method to study protein-DNA binding phenomena in a more realistic spacial environment. By taking TATA-Binding protein as the model protein, we manage to confirm the dominant binding site when there is more than one site exists on a DNA strain. Moreover, influence factors, steric hindrance and Buffer solution composition, of DNA-protein binding phenomenon are illustrated by the control experiments.