A method to identify RNA A-to-I editing targets using I-specific cleavage and exon array analysis

Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung City 807, Taiwan
Molecular and Cellular Probes (Impact Factor: 1.85). 08/2012; 27(1). DOI: 10.1016/j.mcp.2012.08.008
Source: PubMed


RNA A-to-I editing is the most common single-base editing in the animal kingdom. Dysregulations of RNA A-to-I editing are associated with developmental defects in mouse and human diseases. Mouse knockout models deficient in ADAR activities show lethal phenotypes associated with defects in nervous system, failure of hematopoiesis and reduced tolerance to stress. While several methods of identifying RNA A-to-I editing sites are currently available, most of the critical editing targets responsible for the important biological functions of ADARs remain unknown. Here we report a method to systematically analyze RNA A-to-I editing targets by combining I-specific cleavage and exon array analysis. Our results show that I-specific cleavage on editing sites causes more than twofold signal reductions in edited exons of known targets such as Gria2, Htr2c, Gabra3 and Cyfip2 in mice. This method provides an experimental approach for genome-wide analysis of RNA A-to-I editing targets with exon-level resolution. We believe this method will help expedite inquiry into the roles of RNA A-to-I editing in various biological processes and diseases.

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Available from: Hsueh-Wei Chang, Feb 25, 2014
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    • "RNA editing can enhance the RNA and protein diversity [2]. Although five types of RNA editing have been discovered [3], the adenosine-to-inosine (A-to-I) editing is the most common type in higher eukaryotes [4–6]. The A-to-I editing may lead to changes in amino acid type and alternative splicing [7], thereby increasing the complexity of gene expression [8]. "
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