When one is better than two: RNA with dual functions.
The central dogma of biology, until not long ago, held that genetic information stored on DNA molecules was translated into the final protein products through RNA as intermediate molecules. Then, an additional level of complexity in the regulation of genome expression was added, implicating new classes of RNA molecules called non-coding RNA (ncRNA). These ncRNA are also often referred to as functional RNA in that, although they do not contain the capacity to encode proteins, do have a function as RNA molecules. They have been thus far considered as truly non-coding RNA since no ORF long enough to be considered, nor protein, have been associated with them. However, the recent identification and characterization of bifunctional RNA, i.e. RNA for which both coding capacity and activity as functional RNA have been reported, suggests that a definite categorization of some RNA molecules is far from being straightforward. Indeed, several RNA primarily classified as non-protein-coding RNA has been showed to hold coding capacities and associated peptides. Conversely, mRNA, usually regarded as strictly protein-coding, may act as functional RNA molecules. Here, we describe several examples of these bifunctional RNA that have been already characterized from bacteria to mammals. We also extend this concept to fortuitous acquisition of dual function in pathological conditions and to the recently highlighted duality between information carried by a gene and its pseudogenes counterparts.
Université Paris Diderot, CNRS UMR7216, Epigenetics and Cell Fate, Paris, France.
Damien
D
Ulveling
Claire
C
Francastel
Florent
F
Hubé
D000818:Animals; D001419:Bacteria / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D004251:DNA Transposable Elements / Q000235:genetics; D004194:Disease / Q000235:genetics; D004330:Drosophila / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics; D006801:Humans; D051379:Mice; D035683:MicroRNAs / Q000235:genetics; D010944:Plants; D014176:Protein Biosynthesis / Q000235:genetics; D011544:Pseudogenes / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics; D062085:RNA, Long Noncoding; D012333:RNA, Messenger / Q000235:genetics*; D034741:RNA, Small Interfering / Q000235:genetics; D022661:RNA, Untranslated / Q000235:genetics*; D020825:T-Box Domain Proteins / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics; D014158:Transcription, Genetic; D014981:Xenopus; D029867:Xenopus Proteins / Q000235:genetics
C095698:Agr protein, Staphylococcus aureus; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004251:DNA Transposable Elements; D029721:Drosophila Proteins; C405430:ENOD40 RNA; D029968:Escherichia coli Proteins; D035683:MicroRNAs; D012329:RNA, Bacterial; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D022661:RNA, Untranslated; C526013:SgrT protein, E coli; D020825:T-Box Domain Proteins; D015534:Trans-Activators; C465658:Tsix transcript, mouse; C103966:VegT protein, Xenopus; C077885:XIST non-coding RNA; D029867:Xenopus Proteins; C091675:osk protein, Drosophila; C548898:steroid receptor RNA activator, human; C096222:tmRNA