title: A synthetic antimicrobial peptide BTD-S expressed in Arabidopsis thaliana confers enhanced resistance to Verticillium dahliae.
abstract: BTD-S is a synthetic non-cyclic θ-defensin derivative which was previously designed in our laboratory based on baboon θ-defensins (BTDs). It shows robust antimicrobial activity against economically important phytopathogen, Verticillium dahliae. Here, we deduced the coding nucleotide sequence of BTD-S and introduced the gene into wild-type (ecotype Columbia-0) Arabidopsis thaliana plants. Results demonstrated that BTD-S-transgenic lines displayed in bioassays inhibitory effects on the growth of V. dahliae in vivo and in vitro. Based on symptom severity, enhanced resistance was found in a survey of BTD-S-transgenic lines. Besides, crude protein extracts from root tissues of BTD-S-transformed plants significantly restricted the growth of fungal hyphae and the germination of conidia. Also, fungal biomass over time determined by real-time PCR demonstrated the overgrowth of V. dahliae in wild-type plants 2-3 weeks after inoculation, while almost no fungal DNA was detected in aerial tissues of their transgenic progenitors. The result suggested that fungus failed to invade and progress acropetally up to establish a systemic infection in BTD-S-transgenic plants. Moreover, the assessment of basal defense responses was performed in the leaves of WT and BTD-S-transgenic plants. The mitigated oxidative stress and low antioxidase level in BTD-S-transgenic plants revealed that BTD-S acts via permeabilizing target microbial membranes, which is in a category different from hypersensitive response-dependent defense. Taken together, our results demonstrate that BTD-S is a promising gene to be explored for transgenic engineering for plant protection against Verticillium wilt.
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Shen
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Fan
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Noreen
authors.initials: N
authors.lastname: Bibi
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Mi
authors.initials: M
authors.lastname: Ni
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
authors.forename: Shuna
authors.initials: S
authors.lastname: Yuan
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China. xdwang@zju.edu.cn.
authors.forename: Xuede
authors.initials: X
authors.lastname: Wang
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000382:microbiology; D004271:DNA, Fungal / Q000032:analysis; D060467:Disease Resistance; D005813:Genes, Synthetic; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000382:microbiology; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development; D020172:Verticillium / Q000187:drug effects / Q000235:genetics
chemical_list: D023181:Antimicrobial Cationic Peptides; D004271:DNA, Fungal; D010940:Plant Proteins
keywords: Arabidopsis thaliana; BTD-S; Synthetic antimicrobial peptide; Verticillium dahliae