title: MicroRNA156 as a promising tool for alfalfa improvement.
abstract: A precursor of miR156 (MsmiR156d) was cloned and overexpressed in alfalfa (Medicago sativa L.) as a means to enhance alfalfa biomass yield. Of the five predicted SPL genes encoded by the alfalfa genome, three (SPL6, SPL12 and SPL13) contain miR156 cleavage sites and their expression was down-regulated in transgenic alfalfa plants overexpressing miR156. These transgenic plants had reduced internode length and stem thickness, enhanced shoot branching, increased trichome density, a delay in flowering time and elevated biomass production. Minor effects on sugar, starch, lignin and cellulose contents were also observed. Moreover, transgenic alfalfa plants had increased root length, while nodulation was maintained. The multitude of traits affected by miR156 may be due to the network of genes regulated by the three target SPLs. Our results show that the miR156/SPL system has strong potential as a tool to substantially improve quality and yield traits in alfalfa.
authors.affiliation: Agriculture and Agri-Food Canada, London, ON, Canada.|Biology Department, Western University, London, ON, Canada.
authors.forename: Banyar
authors.initials: B
authors.lastname: Aung
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon, SK, Canada.
authors.forename: Margaret Y
authors.initials: MY
authors.lastname: Gruber
authors.affiliation: Agriculture and Agri-Food Canada, London, ON, Canada.
authors.forename: Lisa
authors.initials: L
authors.lastname: Amyot
authors.affiliation: Agriculture and Agri-Food Canada, London, ON, Canada.
authors.forename: Khaled
authors.initials: K
authors.lastname: Omari
authors.affiliation: Agriculture and Agri-Food Canada, St. Foy, QC, Canada.
authors.forename: Annick
authors.initials: A
authors.lastname: Bertrand
authors.affiliation: Agriculture and Agri-Food Canada, London, ON, Canada.|Biology Department, Western University, London, ON, Canada.
authors.forename: Abdelali
authors.initials: A
authors.lastname: Hannoufa
mesh_terms: D018745:Genome, Plant; D000455:Medicago sativa / Q000235:genetics*; D035683:MicroRNAs / Q000235:genetics*; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified
chemical_list: D035683:MicroRNAs
keywords: alfalfa; flowering; forage yield; miR156; nodulation; shoot branching