Studies of new properties and applications of G-quadruplex DNA

Abstract

With the aim of exploring new properties and applications of quadruplex DNA during this study, the discovery of site specific self-cleavage of (1) certain artificially designed and non-biologically relevant assemblies of G-quadruplex (2) G-quadruplexes formed by human telemetric repeats; and (3) G-quadruplexes formed by Oxytricha telemetric repeats were achieved.

In Chapter 2, the design and synthesis of certain non-biologically relevant assemblies of G-quadruplex was accomplished, which was capable of performing self-cleaving actions in a site specific fashion. This designed deoxyribozyme is based on the formation of guanine quartets as its core structure, and geometry of the side loop within the tetraplex columnar structure. In addition, it was also observed that mutations within this structure may result in dramatic or even complete loss of catalytic function as these mutations affect the desired G-quadruplex conformation. Certain factors that affect self-cleavage reactions of G-quadruplexes were explored, such as variation of metal ions, pH values, and temperature dependence. Therefore, with the findings presented in this chapter, it inspired further exploration for new chemical and biological properties of G-quadruplex that have not yet been recognized, which in turn leads to the discovery of self-cleaving activity of biologically relevant G-quadruplex structure such as human and Oxytricha telomere in Chapter 3 and 4.