The most common form of DNA is a right-handed helix or the B-form DNA. DNA can also adopt a variety of alternative conformations, non-B-form DNA secondary structures, including the DNA G-quadruplex (DNA-G4). Furthermore, besides stem-loops that yield A-form double-stranded RNA, non-canonical RNA G-quadruplex (RNA-G4) secondary structures are also observed. Recent bioinformatics analysis of the whole-genome and transcriptome obtained using G-quadruplex-specific antibodies and ligands, revealed genomic positions of G-quadruplexes. In addition, accumulating evidence pointed to the existence of these structures under physiologically- and pathologically-relevant conditions, with functional roles in vivo. In this review, we focused on DNA-G4 and RNA-G4, which may have important roles in neuronal function, and reveal mechanisms underlying neurological disorders related to synaptic dysfunction. In addition, we mention the potential of G-quadruplexes as therapeutic targets for neurological diseases.
Keywords: DNA; G-quadruplex; RNA; neurobiology; neurological disease.