RNA editing of plastid-encoded genes

Abstract

RNA editing is post-transcriptional modification to RNA molecules. In plants, RNA editing primarily occurs to two energy-producing organelles: plastids and mitochondria. Organelle RNA editing is often viewed as a mechanism of correction to compensate for defects or mutations in haploid organelle genomes. A common type of organelle RNA editing is deamination from cytidine to uridine. Cytidine-to-uridine plastid RNA editing is carried out by the RNA editing complex which consists of at least four types of proteins: pentatricopeptide repeat proteins, RNA editing interacting proteins/multiple organellar RNA editing factors, organelle RNA recognition motif proteins, and organelle zinc-finger proteins. The four types of RNA editing factors work together to carry out RNA editing site recognition, zinc cofactor binding, and cytidine-to-uridine deamination. In addition, three other types of proteins have been found to be important for plastid RNA editing. These additional proteins may play a regulatory or stabilizing role in the RNA editing complex.