Organellar RNA editing

Abstract

RNA editing is a term used for a number of mechanistically different processes that alter the nucleotide sequence of RNA molecules to differ from the gene sequence. RNA editing occurs in a wide variety of organisms and is particularly frequent in organelle transcripts of eukaryotes. The discontiguous phylogenetic distribution of mRNA editing, the mechanistic differences observed in different organisms, and the nonhomologous editing machinery described in different taxonomic groups all suggest that RNA editing has appeared independently several times. This raises questions about the selection pressures acting to maintain editing that are yet to be completely resolved. Editing tends to be frequent in organisms with atypical organelle genomes and acts to correct the effect of DNA mutations that would otherwise compromise the synthesis of functional proteins. Additional functions of editing in generating protein diversity or regulating gene expression have been proposed but so far lack widespread experimental evidence, at least in organelles.

Salt stress affects mRNA editing in soybean chloroplasts

“…Alterations in metabolic pathways, in specific signals like redox state, or in protein structures can lead to disruption in plastid activity and, consecutively, in plant yield. RNA editing, a post transcriptional process, consists in nucleotide conversions from cytosine (C) to uracil (U), or, less frequently, from U to C. This process, also present in mitochondria, is performed by deamination and amination reactions (Chateigner-Boutin and Small, 2011; Hayes et al ., 2015). Usually, editing events preserve amino acids that are phylogenetically conserved by restoring the codon sequence.…”

RNA Processing Factor 7 and Polynucleotide Phosphorylase Are Necessary for Processing and Stability of nad2 mRNA in Arabidopsis Mitochondria

“…[13][14][15][16][17][18] But it is assumed that the majority of P-class PPR proteins cooperates with other proteins, which by the nature of their enzymatic activity seem to determine the way in which a given RNA is processed. A general concerted function of P-class PPR proteins and exoribonucleases has been suggested for the post-transcriptional Keywords: Arabidopsis thaliana, mitochondria, RNA, 5′ end processing, pentatricopeptide repeat proteins, RNA processing factor, polynucleotide phosphorylase post-transcriptional maturation of plant mitochondrial transcripts requires several steps.…”

Gene rearrangements in gekkonid mitochondrial genomes with shuffling, loss, and reassignment of tRNA genes

“…RNA editing could also change the decoding specificity of tRNAs. RNA editing is known to occur in various metazoan mitochondrial tRNAs ([51, 52] and refs. therein).…”