title: RNA self-cleavage activated by ultraviolet light-induced oxidation.
abstract: A novel UV-C-light-induced ribozyme activity was discovered within the highly structured 5'-genomic regions of both Hepatitis C Virus (HCV) and the related Classic Swine Fever Virus (CSFV). Cleavage is mediated by exposure to UV-C light but not by exogenous oxygen radicals. It is also very selective, occurring at base positions HCV C(79) and CSFV A(45) in some molecules and at the immediately adjacent 5'-positions HCV U(78) and CSFV U(44) in others. Among other reaction products, the majority of biochemically active products detected contained 3'-phosphate and 5'-phosphate-end groups at the newly generated termini, along with a much lower amount of 3'-hydroxyl end group. While preservation of an E-loop RNA structure in the vicinity of the cleavage site was a requisite for HCV RNA self-cleavage, this was not the case for CSFV RNA. The short size of the reactive domains (~33 nt), which are compatible with primitive RNA motifs, and the lack of sequence homology, indicate that as-yet unidentified UV-activated ribozymes are likely to be found throughout structured RNAs, thereby providing clues to whether early RNA self-cleavage events were mediated by photosensitive RNA structures.
authors: Laboratory of RNA Archeology, Instituto de Parasitología y Biomedicina 'López-Neyra', CSIC, Armilla, 18100 Granada, Spain.
authors: Ascensión
authors: A
authors: Ariza-Mateos
authors: Samuel
authors: S
authors: Prieto-Vega
authors: Rosa
authors: R
authors: Díaz-Toledano
authors: Alex
authors: A
authors: Birk
authors: Hazel
authors: H
authors: Szeto
authors: Ignacio
authors: I
authors: Mena
authors: Alfredo
authors: A
authors: Berzal-Herranz
authors: Jordi
authors: J
authors: Gómez
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D006692:Classical Swine Fever Virus / Q000235:genetics; D016174:Hepacivirus / Q000235:genetics; D017665:Hydroxyl Radical / Q000737:chemistry; D009154:Mutation; D010084:Oxidation-Reduction; D016337:RNA, Catalytic / Q000737:chemistry* / Q000378:metabolism / Q000528:radiation effects*; D012367:RNA, Viral / Q000737:chemistry* / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D016337:RNA, Catalytic; D012367:RNA, Viral; D017665:Hydroxyl Radical