title: RNA editing by mammalian ADARs.
abstract: The main type of RNA editing in mammals is the conversion of adenosine to inosine which is translated as if it were guanosine. The enzymes that catalyze this reaction are ADARs (adenosine deaminases that act on RNA), of which there are four in mammals, two of which are catalytically inactive. ADARs edit transcripts that encode proteins expressed mainly in the CNS and editing is crucial to maintain a correctly functioning nervous system. However, the majority of editing has been found in transcripts encoding Alu repeat elements and the biological role of this editing remains a mystery. This chapter describes in detail the different ADAR enzymes and the phenotype of animals that are deficient in their activity. Besides being enzymes, ADARs are also double-stranded RNA-binding proteins, so by binding alone they can interfere with other processes such as RNA interference. Lack of editing by ADARs has been implicated in disorders such as forebrain ischemia and Amyotrophic Lateral Sclerosis (ALS) and this will also be discussed.
authors.affiliation: MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh, UK.
authors.forename: Marion
authors.initials: M
authors.lastname: Hogg
authors.forename: Simona
authors.initials: S
authors.lastname: Paro
authors.forename: Liam P
authors.initials: LP
authors.lastname: Keegan
authors.forename: Mary A
authors.initials: MA
authors.lastname: O'Connell
mesh_terms: D000241:Adenosine / Q000235:genetics / Q000378:metabolism; D000243:Adenosine Deaminase / Q000235:genetics* / Q000378:metabolism*; D020087:Alu Elements; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D000818:Animals; D002490:Central Nervous System / Q000378:metabolism; D056726:Genetic Association Studies; D006801:Humans; D007288:Inosine / Q000235:genetics / Q000378:metabolism; D008297:Male; D008322:Mammals / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics; D017393:RNA Editing; D034622:RNA Interference; D012330:RNA, Double-Stranded / Q000378:metabolism*; D016601:RNA-Binding Proteins; D051381:Rats
chemical_list: D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins; D007288:Inosine; C567955:ADARB1 protein, human; D000243:Adenosine Deaminase; D000241:Adenosine