title: Virus induced gene silencing of a DEFICIENS ortholog in Nicotiana benthamiana.
abstract: Traditionally, developmental studies in plant biology have suffered from the lack of a convenient means to study gene function in non-model plant species. Here we show that virus-induced gene silencing (VIGS) is an effective new tool to study the function of orthologs of floral homeotic genes such as DEFICIENS (DEF) in non-model systems. We used a tobacco rattle virus (TRV)-based VIGS approach to study the function of the Nicotiana benthamiana DEF ortholog (NbDEF). Silencing of NbDEF in N. benthamiana using TRV-VIGS was similar to that of Antirrhinum def and Arabidopsis ap3 mutants and caused transformation of petals into sepals and stamens into carpels. Molecular analysis of the NbDEF -silenced plants revealed a dramatic reduction of the levels of NbDEF mRNA and protein in flowers. NbDEF silencing was specific and has no effect on the mRNA levels of NbTM6, the closest paralog of NbDEF. A dramatic reduction of the levels of N. benthamiana GLOBOSA (NbGLO) mRNA and protein was also observed in flowers of NbDEF-silenced plants, suggesting that cross-regulation of this GLO-like gene by NbDEF. Taken together, our results suggest that NbDEF is a functional homolog of Antirrhinum DEF. Our results are significant in that they show that TRV efficiently induces gene silencing in young and differentiating flowers and that VIGS is a promising new tool for analyses of developmental gene function in non-model organisms.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA.
authors.forename: Yule
authors.initials: Y
authors.lastname: Liu
authors.forename: Naomi
authors.initials: N
authors.lastname: Nakayama
authors.forename: Michael
authors.initials: M
authors.lastname: Schiff
authors.forename: Amy
authors.initials: A
authors.lastname: Litt
authors.forename: Vivian F
authors.initials: VF
authors.lastname: Irish
authors.forename: S P
authors.initials: SP
authors.lastname: Dinesh-Kumar
mesh_terms: D026281:DEFICIENS Protein / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D005822:Genetic Vectors / Q000235:genetics; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D010942:Plant Viruses / Q000235:genetics*; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism / Q000821:virology
chemical_list: D026281:DEFICIENS Protein; C081703:GLO protein, Nicotiana tabacum; D010940:Plant Proteins; D012333:RNA, Messenger