Studying the interaction between pentameric oligonucleotides and recombinant signaling proteins and receptors

Abstract Oligonucleotides are short fragments of DNA or RNA that play a significant role in many fundamental biological processes, such as gene regulation, translation, DNA replication and repair, immune response, and others. The aim of this work was to synthesize, purify and study the interaction of oligonucleotides (OLN) with recombinant signaling proteins, in particular interferon α2-β, insulin, their receptors, and somatropin , using docking. in in silico and fluorescence spectroscopy in vitro . For the analysis of interactions, the Stern-Volmer equation in its general and modified forms, and the Gill equation were used, which allowed to obtain the binding and binding constants. The synthesis of oligonucleotides was carried out using the solid-phase phosphoamidite method, which provides high efficiency and specificity of synthesis. After that, the oligonucleotides were purified by the solid-phase extraction method, which allowed to remove by-products and impurities, which was verified by spectral analysis. Fluorometric titration showed the binding of OLNs to proteins in the medium affinity zone, forming non-fluorescent complexes, with the most active interaction being with shorter oligonucleotides. Negative cooperative binding of INS with rG5 was established. Negative cooperative binding of the INSR receptor with the oligoribonucleotide rA5 and the INFR receptor with the rG5, rA5, A5 preparations was also shown. At the same time, all proteins bound only to one ligand, A, namely the G5 oligonucleotide. Understanding the mechanisms of protein-oligonucleotide interactions may open new possibilities for the treatment of various diseases. Oligonucleotides can be used for the development of new antibiotics and antiviral drugs, the treatment of cancer and genetic diseases. Keywords: INTERFERON, INSULIN, RECEPTOR, SOMATOTROPIN, PROTEIN-LIGAND INTERACTION, SPECTROSCOPY, OLIGORIBONUCLEOTIDE, OLIGODEZOXYNUCLEOTIDE, DOCKING.