Table 1.

Examples of RNAs with dual functions

Organism	Type	Role	Refs
Bacteria
RNAIII (S. aureus)	RNA	Modulates the production of toxins and enzymes by base-pairing on mRNA targets	[132]
	Protein	Controls the switch between early and late expression of several exotoxins	[133]
SgrS (E. coli)	RNA	Regulate sugar stress (prolonged stress)	[134]
	Protein	Regulate sugar stress (early response)	[134]
SR1 (Bacillus)	RNA	Regulation of arginine catabolism	[135]
	Protein	SR1P binds and stabilizes the gapA operon mRNAs	[135]
tmRNA (Bacteria)	RNA	Function as a tRNA by adding alanine to a stalled polypeptide chain	[135]
	Protein	Function as a mRNA by incorporating a degradation tag to the polypeptide chain	[135]
miPEP171b (M. truncatula)	RNA	Downregulates target genes involved in root development	[136]
	Protein	Enhances the accumulation of its corresponding mature miRNA	[136]
miPEP165a (A. thaliana)	RNA	Downregulates target genes involved in root development	[136]
	Protein	Enhances the accumulation of its corresponding mature miRNA	[136]
Plants
Enod40	RNA	Confers specificity for the recognition of mRNA targets of MtRBP1	[137]
	Protein	Affects MtRBP1 localization during nodule development	[137]
Insects
Oskar (Drosophila)	RNA	Scaffold for the complexes essential for development of the oocyte (early stage)	[138]
	Protein	Scaffold for the complexes essential for development of the oocyte (late stage)	[138]
Fish
Sqt (Danio rerio)	RNA	Deliver/sequester maternal factors for dorsal specification	[139]
	Protein	Deliver/sequester maternal factors for dorsal specification	[139]
Amphibians
VegT (Xenopus)	RNA	Organization of the cytokeratin cytoskeleton	[140]
	Protein	Transcription factor of the T-box family	[140]
Mammals (mainly human and mice)
p53	RNA	Stimulates p53 translation and prevents p53 protein from Mdm2-induced degradation	[115]
	Protein	Tumour suppressor	[115]
SRA1	RNA	Co-activator of transcription factors	[12]
	Protein	Inhibitor of the co-activation function of SRA RNA	[12]
circ-ZNF609	RNA	Serves as a sponge for miR-150-5p and controls cell proliferation	[141]
	Protein	Control of myoblast proliferation	[120]
ASCC3	RNA	Counteracts the function of the protein-coding isoform	[38]
	Protein	Negative regulator of the host defence response	[38]
LINC00961/SPAR	RNA	has as an anti-angiogenic role by inhibiting the function of Tβ4 protein	[108]
	Protein	Involved in muscle regeneration/has a pro-angiogenic role by binding the SYNE1 protein	[107]
HIC	RNA	Activates P-TEFb by displacing 7SK RNA	[142]
	Protein	Inhibits P-TEFb transcription	[143]
Irs-1	RNA	Inhibits myoblasts differentiation through complementary sequence to Rb mRNA	[144]
	Protein	Coordinates skeletal muscle growth and metabolism	[145]
apoE/apoE-I3	RNA	apoE-I3 controls apoE expression in neurons	[146]
	Protein	Involved in lipid transport system	[146]
PNUTS	RNA	regulates EMT migration and invasion in vitro through its miR-205 interaction	[39]
	Protein	functions as a proto-oncogene by sequestering PTEN	[147]