title: Predicting sites of ADAR editing in double-stranded RNA.
abstract: ADAR (adenosine deaminase that acts on RNA) editing enzymes target coding and noncoding double-stranded RNA (dsRNA) and are essential for neuronal function. Early studies showed that ADARs preferentially target adenosines with certain 5' and 3' neighbours. Here we use current Sanger sequencing protocols to perform a more accurate and quantitative analysis. We quantified editing sites in an ∼800-bp dsRNA after reaction with human ADAR1 or ADAR2, or their catalytic domains alone. These large data sets revealed that neighbour preferences are mostly dictated by the catalytic domain, but ADAR2's dsRNA-binding motifs contribute to 3' neighbour preferences. For all proteins, the 5' nearest neighbour was most influential, but adjacent bases also affected editing site choice. We developed algorithms to predict editing sites in dsRNA of any sequence, and provide a web-based application. The predictive power of the algorithm on fully base-paired dsRNA, compared with biological substrates containing mismatches, bulges and loops, elucidates structural contributions to editing specificity.
authors.affiliation: Department of Biochemistry, University of Utah, 15 N Medical Drive East, Room 4800, Salt Lake City, Utah 84112, USA.
authors.forename: Julie M
authors.initials: JM
authors.lastname: Eggington
authors.forename: Tom
authors.initials: T
authors.lastname: Greene
authors.forename: Brenda L
authors.initials: BL
authors.lastname: Bass
mesh_terms: D000243:Adenosine Deaminase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D020134:Catalytic Domain; D006801:Humans; D008969:Molecular Sequence Data; D017393:RNA Editing; D012330:RNA, Double-Stranded / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins
chemical_list: D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins; C567955:ADARB1 protein, human; D000243:Adenosine Deaminase