RNA Editing and Human Disorders

Abstract

Ribonucleic acid (RNA) editing can be broadly defined as any process that changes the sequence of an RNA molecule in a way that could be encoded within the genome. These small, targeted changes at the RNA level can have profound effects on gene expression. Such programmed alterations can be controlled in a tissue‐specific or developmentally regulated fashion, providing an alternative means of augmenting the information encoded within the genome. In mammalian cells, cytidine to uridine (C to U) and adenosine to inosine (A to I) changes have been observed in both coding and noncoding sequences, including microRNAs, and dysregulation has been linked to disease states. Editing enzymes are often essential, and can act on viral, as well as cellular RNAs. Some human pathogens utilise additional forms of RNA editing for gene expression; these forms of editing provide potential therapeutic targets. Key Concepts: RNA editing is a means of generating genetic diversity that is far more flexible than simply encoding information at the genomic level. Editing is regulated both developmentally and spatially, and dysregulation can have serious consequences. Most editing events in humans fall outside of coding regions; the functional consequences of many of these changes are still being elucidated, but will likely be far‐reaching. Editing can impact the function of noncoding RNAs, including those involved in RNA silencing. RNA editing can have both antiviral and proviral effects.

In vitrorecapitulation of the site-specific editing (to wild-type) of mutantIDSmRNA transcripts, and the characterization of IDS protein translated from the edited mRNAs

“…Cytidine (C) to uridine (U) and adenosine (A) to inosine (I) transitions are the best characterized mammalian mRNA editing mechanisms reported to date. Generally, in mammalian cells, C to U and A to I changes have been observed in both coding and noncoding sequences, including microRNAs; dysregulation can lead to pathogenesis (Gott, ; Grohmann et al., ; Maas, Kawahara, Tamburro, & Nishikura, ; Ramaswami & Li, ).…”