G-quadruplexes (G4s) are distinct nucleic acid secondary structures formed by guanine-rich sequences in both DNA and RNA. These structures readily form and fulfill diverse biological functions. The structural diversity of G4s is influenced by several factors, including their strand orientation, glycosidic bond angles, and loop configurations. G4s are widely distributed in functionally significant genomic regions, including telomeres, promoter regions, exons, 5' untranslated region (5' UTR), intron region, and 3' untranslated region (3' UTR). G4s are implicated in critical biological processes, including telomere elongation, DNA replication, DNA damage repair, transcription, translation, and epigenetic regulation. This overview offers a comprehensive analysis of the determinants of G4 structure and their impact on associated biological processes. Briefly, it describes the effects of G4s on cancers, viruses, and other pathogenic substances. This overview aims to contribute new ideas for the regulation of related mechanisms and their potential impact on the treatment strategies of related diseases. This article is categorized under: RNA Structure and Dynamics > RNA Structure, Dynamics and Chemistry RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems.
Keywords: G‐quadruplex; diseases; function; structure.
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