22 March 2000 Novel molecular beacon DNA probes for protein-nucleic acid interaction studies
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Proceedings Volume 3926, Advances in Nucleic Acid and Protein Analyses, Manipulation, and Sequencing; (2000) https://doi.org/10.1117/12.380521
Event: BiOS 2000 The International Symposium on Biomedical Optics, 2000, San Jose, CA, United States
We report a novel approach to study protein-nucleic acid interactions by using molecular beacons (MBs). Molecular beacons are hairpin-shaped DNA oligonucleotide probes labeled with a fluorophore and a quencher, and can report the presence of target DNA/RNA sequences. MBs can also report the existence of single-stranded DNA binding proteins (SSB) through non-sequence specific binding. The interaction between SSB and MB has resulted in significant fluorescence restoration of the MB. The fluorescence enhancement brought by SSB and by complementary DNA is very comparable. The molar ratio of the binding between SSB and the molecular beacon is 1:1 with a binding constant of 2 X 107 M-1. Using the MB-SSB binding, we are able to determine SSB at 2 X 10-10 M with a conventional spectrometer. We have also applied MB DNA probes for the analysis of an enzyme lactic dehydrogenase (LDH), and for the investigation of its binding properties with ssDNA. The biding process between MB and different isoenzymes of LDH has been studied. We also show that there are significant differences in MB binding affinity to different proteins, which will enable selective binding studies of a variety of proteins. This new approach is potentially useful for protein-DNA/RNA interaction studies that require high sensitivity, speed and convenience. The results also open the possibility of using easily obtainable, custom designed, modified DNA molecules for studies of drug interactions and targeting. Our results demonstrate that MB can be effectively used for sensitive protein quantitation and for efficient protein-DNA interaction studies. MB has the signal transduction mechanism built within the molecule, and can thus be used for quick protein assay development and for real-time measurements.
© (2000) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jianwei Jeffrey Li, Jianwei Jeffrey Li, John Perlette, John Perlette, Xiaohong Fang, Xiaohong Fang, Shannon Kelley, Shannon Kelley, Weihong Tan, Weihong Tan, } "Novel molecular beacon DNA probes for protein-nucleic acid interaction studies", Proc. SPIE 3926, Advances in Nucleic Acid and Protein Analyses, Manipulation, and Sequencing, (22 March 2000); doi: 10.1117/12.380521; https://doi.org/10.1117/12.380521

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