New insights on non-canonical DNA structures: G-Quadruplex folding of RPGR exon ORF15 might impair photoreceptor vesicular trafficking and ciliogenesis

During last years it has becoming evident that non-Watson– Crick base pairing, resulting in the assembly of alternative DNA secondary structures, also occurs in the genome. Such noncanonical structures, called non-B form DNA, include the G-quadruplexes, stacked nucleic acid structures that form within G-rich DNA or RNA sequences. Dysregulation of DNA-G4 is associated with human disorders, including neurological dysfunction and accelerated ageing, even if its role in neurophysiology/neuropathology has not yet been fully elucidated. We present results coming from our recent experiments on X-linked retinitis pigmentosa (OMIM 26800), a group of hereditary disorders that can lead to blindness because of photoreceptor degenerations. The most frequently mutated X-linked retinitis pigmentosa genes is RPGR (RP3), and codes for a protein with a series of six RCC1-