Modulation of MicroRNA Expression and Function by ADARs
MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by preventing the translation of specific messenger RNAs. Adenosine deaminases acting on RNAs (ADARs) catalyze adenosine-to-inosine (A-to-I) RNA editing, the conversion of adenosines into inosines, in double-stranded RNAs. Because inosine preferentially base pairs with cytidine, this conversion is equivalent to an adenosine to guanosine change. Over the past seven years, an increasing number of edited adenosines have been identified in miRNAs. Editing of miRNAs affects their biogenesis, causes their degradation or alters the set of messenger RNAs that they regulate. Recently, ADARs have been shown to also affect the miRNA phenomenon by sequestering miRNAs or by editing the messenger RNAs they regulate. This article reviews the recent attempts to identify miRNA editing sites and elucidate the effects of ADARs on miRNA expression and function.
Adenosine deaminase acting on RNA
Precursor messenger RNA
Small interfering RNA
Tudor staphylococcal nuclease
DNA fragmentation factor alpha
Phosphoribosyl pyrophosphate synthetase 1