RNA editing helps identify cellular RNAs

Sci. Signal.  08 Sep 2015:
Vol. 8, Issue 393, pp. ec260
DOI: 10.1126/scisignal.aad3741

Adenosine bases in messenger RNA (mRNAs) can be enzymatically modified and changed into inosine bases. This RNA “editing” is mediated by adenosine deaminase acting on RNA (ADAR) enzymes. Liddicoat et al. show that the in vivo targets of the principal editing enzyme, ADAR1, are long double-stranded RNA (dsRNA) structures in noncoding portions of cellular mRNAs. ADAR1-directed editing of these cellular targets is critical to avoid activation of an immune response to dsRNA in the cytoplasm, because dsRNA is also a marker of viral infection.

B. J. Liddicoat, R. Piskol, A. M. Chalk, G. Ramaswami, M. Higuchi, J. C. Hartner, J. B. Li, P. H. Seeburg, C. R. Walkley, RNA editing by ADAR1 prevents MDA5 sensing of endogenous dsRNA as nonself. Science 349, 1115–1120 (2015). [Abstract] [Full Text]