title: Primary transcripts of microRNAs encode regulatory peptides.
abstract: MicroRNAs (miRNAs) are small regulatory RNA molecules that inhibit the expression of specific target genes by binding to and cleaving their messenger RNAs or otherwise inhibiting their translation into proteins. miRNAs are transcribed as much larger primary transcripts (pri-miRNAs), the function of which is not fully understood. Here we show that plant pri-miRNAs contain short open reading frame sequences that encode regulatory peptides. The pri-miR171b of Medicago truncatula and the pri-miR165a of Arabidopsis thaliana produce peptides, which we term miPEP171b and miPEP165a, respectively, that enhance the accumulation of their corresponding mature miRNAs, resulting in downregulation of target genes involved in root development. The mechanism of miRNA-encoded peptide (miPEP) action involves increasing transcription of the pri-miRNA. Five other pri-miRNAs of A. thaliana and M. truncatula encode active miPEPs, suggesting that miPEPs are widespread throughout the plant kingdom. Synthetic miPEP171b and miPEP165a peptides applied to plants specifically trigger the accumulation of miR171b and miR165a, leading to reduction of lateral root development and stimulation of main root growth, respectively, suggesting that miPEPs might have agronomical applications.
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Dominique
authors: D
authors: Lauressergues
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Jean-Malo
authors: JM
authors: Couzigou
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Hélène San
authors: HS
authors: Clemente
authors: Fédération de Recherches FR3450 CNRS, 31326 Castanet-Tolosan, France.
authors: Yves
authors: Y
authors: Martinez
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Christophe
authors: C
authors: Dunand
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Guillaume
authors: G
authors: Bécard
authors: 1] Université de Toulouse, UPS, UMR5546, Laboratoire de Recherche en Sciences Végétales, 31326 Castanet-Tolosan, France [2] Centre National de la Recherche Scientifique, CNRS, UMR5546, 31326 Castanet-Tolosan, France.
authors: Jean-Philippe
authors: JP
authors: Combier
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D046913:Medicago truncatula / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics; D010455:Peptides / Q000235:genetics*; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D012322:RNA Precursors / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D035683:MicroRNAs; D010455:Peptides; D010940:Plant Proteins; D012322:RNA Precursors