title: Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta.
abstract: PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches'-broom (AYWB) phytoplasma and Peanut witches'-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies.
authors.affiliation: Institute of Biotechnology, National Taiwan University, Taipei, Taiwan.
authors.forename: Sin-Fen
authors.initials: SF
authors.lastname: Hu
authors.affiliation: Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan.
authors.forename: Yu-Hsin
authors.initials: YH
authors.lastname: Huang
authors.affiliation: Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan.
authors.forename: Chan-Pin
authors.initials: CP
authors.lastname: Lin
authors.affiliation: Department of Agronomy, National Taiwan University, Taipei, Taiwan.
authors.forename: Li-Yu Daisy
authors.initials: LY
authors.lastname: Liu
authors.affiliation: Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, Taiwan.
authors.forename: Syuan-Fei
authors.initials: SF
authors.lastname: Hong
authors.affiliation: Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan.
authors.forename: Chiao-Yin
authors.initials: CY
authors.lastname: Yang
authors.affiliation: Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, Taiwan.
authors.forename: Hsiao-Feng
authors.initials: HF
authors.lastname: Lo
authors.affiliation: Joint Center for Instruments and Researches, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
authors.forename: Ting-Yu
authors.initials: TY
authors.lastname: Tseng
authors.affiliation: Institute of Biotechnology, National Taiwan University, Taipei, Taiwan.
authors.forename: Wei-Yao
authors.initials: WY
authors.lastname: Chen
authors.affiliation: Institute of Biotechnology, National Taiwan University, Taipei, Taiwan; Genome and Systems Biology Degree Program, National Taiwan University, Taipei, Taiwan; Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Shih-Shun
authors.initials: SS
authors.lastname: Lin
mesh_terms: D000818:Animals; D000917:Antibody Formation; D017360:Arabidopsis / Q000254:growth & development / Q000382:microbiology* / Q000821:virology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015153:Blotting, Western; D035264:Flowers / Q000254:growth & development / Q000382:microbiology* / Q000821:virology; D054884:Host-Pathogen Interactions; D007303:Insect Vectors / Q000235:genetics / Q000472:pathogenicity; D045582:Phytoplasma / Q000378:metabolism / Q000472:pathogenicity*; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000254:growth & development / Q000382:microbiology* / Q000821:virology; D030821:Plants, Genetically Modified / Q000254:growth & development / Q000382:microbiology* / Q000821:virology; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017806:Tymovirus / Q000472:pathogenicity*
chemical_list: D029681:Arabidopsis Proteins; D012333:RNA, Messenger