Surface plasmon resonance (SPR) imaging sensors are high-sensitive, label-free, real-time and high-throughput, which can monitor interactions between biomolecules. it can also provide the binding kinetic parameters between different biomolecules. Moreover, specific protein-DNA interactions play a central role in transcription and other biological processes. A comprehensive characterization of protein-DNA interactions should include a lot of information such as, binding affinity, kinetics, sequence specificity, and binding stoichiometry. Protein–DNA interactions are studied mainly using either electrophoretic mobility shift assays (EMSAs) or surface plasmon resonance (SPR) spectroscopy. The latter has emerged as a powerful alternative to conventional biochemistry methods, due to its ability of real-time measurement and the versatilities for studying affinity, kinetics, stoichiometry, sequence specificity, etc. The surface plasmon resonance (SPR) technique, a label independent technique, has emerged as a powerful alternative to conventional biochemistry methods for studying bioaffinity interactions, including protein-DNA binding that may involve purified proteins and a multiprotein complex in nuclear extracts.
A two-step antibody approach for an SPR study of estrogen receptor a (ERα)-DNA interactions
A two-step antibody approach for an SPR study of estrogen receptor a (ERα)–DNA interactions have been developed, in which nuclear extracts prepared from MCF-7 breast cancer cells were used as the source of ERα protein. Following the binding of nuclear extracts to surface-immobilized estrogen response elements, rabbit anti- ERα antibody followed by a secondary antibody (goat anti-rabbit IgG) were applied to recognize the bound ERα and amplify the signals, respectively. Through a series of experiments, we have demonstrated that the magnitude of the binding signals from the secondary antibody reflects the affinity by which ERα binds to different DNA sequences. The detection sensitivity is determined by the amount of nuclear extracts and the concentration of primary antibody used. The sequence specificity of the nuclear ERα measured using the two-step antibody approach is in agreement with that measured for recombinant ERα protein.
The company has advanced technical support, strong comprehensive strength, rich quality management experience, and huge scale effect. Creative Peptides provides comprehensive peptide analysis services to help our customers speed up their research and tailor our services to meet their needs. Typical services of surface plasmon resonance imaging in protein/DNA interactions includes (not limited):
- Quantify the binding affinity of protein/DNA interactions.
- Measure the binding sites of protein/DNA interactions.
- Monitor the binding of protein to surface-immobilized DNA or the binding of DNA to mobilized protein.
1. Su, X., Neo, S. J., Peh, W. Y., & Thomsen, J. S. (2008). A two-step antibody strategy for surface plasmon resonance spectroscopy detection of protein–DNA interactions in nuclear extracts. Analytical biochemistry, 376(1), 137-143.
2. Teh, H. F., Peh, W. Y., Su, X., & Thomsen, J. S. (2007). Characterization of protein− DNA interactions using surface plasmon resonance spectroscopy with various assay schemes. Biochemistry, 46(8), 2127-2135.