title: Tissue-specific and pathogen-inducible expression of a fusion protein containing a Fusarium-specific antibody and a fungal chitinase protects wheat against Fusarium pathogens and mycotoxins.
abstract: Fusarium head blight (FHB) in wheat and other small grain cereals is a globally devastating disease caused by toxigenic Fusarium pathogens. Controlling FHB is a challenge because germplasm that is naturally resistant against these pathogens is inadequate. Current control measures rely on fungicides. Here, an antibody fusion comprised of the Fusarium spp.-specific recombinant antibody gene CWP2 derived from chicken, and the endochitinase gene Ech42 from the biocontrol fungus Trichoderma atroviride was introduced into the elite wheat cultivar Zhengmai9023 by particle bombardment. Expression of this fusion gene was regulated by the lemma/palea-specific promoter Lem2 derived from barley; its expression was confirmed as lemma/palea-specific in transgenic wheat. Single-floret inoculation of independent transgenic wheat lines of the T3 to T6 generations revealed significant resistance (type II) to fungal spreading, and natural infection assays in the field showed significant resistance (type I) to initial infection. Gas chromatography-mass spectrometry analysis revealed marked reduction of mycotoxins in the grains of the transgenic wheat lines. Progenies of crosses between the transgenic lines and the FHB-susceptible cultivar Huamai13 also showed significantly enhanced FHB resistance. Quantitative real-time PCR analysis revealed that the tissue-specific expression of the antibody fusion was induced by salicylic acid drenching and induced to a greater extent by F. graminearum infection. Histochemical analysis showed substantial restriction of mycelial growth in the lemma tissues of the transgenic plants. Thus, the combined tissue-specific and pathogen-inducible expression of this Fusarium-specific antibody fusion can effectively protect wheat against Fusarium pathogens and reduce mycotoxin content in grain.
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: He-Ping
authors.initials: HP
authors.lastname: Li
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Jing-Bo
authors.initials: JB
authors.lastname: Zhang
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Hong-Jie
authors.initials: HJ
authors.lastname: Du
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Qi-Yong
authors.initials: QY
authors.lastname: Wei
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yang
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Xian-Wei
authors.initials: XW
authors.lastname: Kong
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan, China.|College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.|National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, China.
authors.forename: Yu-Cai
authors.initials: YC
authors.lastname: Liao
mesh_terms: D000908:Antibodies, Fungal / Q000276:immunology*; D002688:Chitinases / Q000235:genetics; D005670:Fusarium / Q000235:genetics / Q000276:immunology*; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000235:genetics; D009183:Mycotoxins / Q000378:metabolism*; D009928:Organ Specificity; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D030821:Plants, Genetically Modified; D060888:Real-Time Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins; D014908:Triticum / Q000235:genetics / Q000276:immunology* / Q000382:microbiology
chemical_list: D000908:Antibodies, Fungal; D009183:Mycotoxins; D011993:Recombinant Fusion Proteins; D002688:Chitinases
keywords: Fusarium head blight; antibody fusion; chitinase; mycotoxins; pathogen-inducible expression; tissue-specific promoter; transgenic wheat