Zarudnaya M. Structural transitions in homopolyribonucleotides and their biological role

The work is devoted to the investigation of physico-chemical characteristics of homopolyribonucleotides and their structural transitions depending on the environmental conditions. The values of the effective diameter of the DNA double helix have been first determined at the intermediate ionic strength of solution. Structural transitions in homopolyribonucleotides have been first investigated by electrophoresis and proton buffer capacity methods. The dynamics of the transitions has been studied in details, some new forms being revealed. The molecular mechanisms of formation of several forms have been proposed. The molecular models of participation of self-associated oligo(A)-duplex and G-quadruplexes in some biological processes have been presented. The database of poly(A)-sites of human pre-mRNA has been compiled. It has been shown that the most of the transcripts contain different auxiliary elements and also sequences, which are capable to form G-quadruplexes. A large-scale phylogenetic analysis of poly(A)-sites of the HIV-1 pre-mRNA has been performed.