Yu-Cai Liao
Huazhong Agricultural University, China
Title: Specific and inducible disease resistance antibody molecules against Fusarium pathogens and mycotoxins in plants
Biography
Biography: Yu-Cai Liao
Abstract
Fusarium pathogens cause serious plant diseases affecting wheat, barley, maize and other cereals productions globally. The fungal pathogens produce various mycotoxins that are highly toxic to human and domestic animals. Plant germplasms with natural resistance against Fusarium pathogens and mycotoxins are inadequate. A recombinant antibody isolated by phage display from a chicken-derived immunocompetent antibody library displayed Fusarium genus-specificity. Constitutive expression in plants of the antibody or antibody fusions with different peptides conferred durable resistance specific to Fusarium pathogens with no effect on non-Fusarium organisms. This antibody-mediated pathogen-specific resistance was also regulated by Fusarium-inducible promoter to generate active immunity in plants. Wheat plants expressing the antibody-antifungal peptide fusion protein showed significantly enhanced resistance against Fusarium pathogens and mycotoxins; the infection of the wheat plants by Fusarium pathogens rapidly activated the expression of this antibody fusion and this activation played a profound role in the disease resistance. This resistance was genetically stable and could be transferred to different wheat varieties. Further characterization of the fungal antigen recognized by the Fusarium genus-specific antibody demonstrated that a highly conserved single gene-encoded antigen that specifically interacted with the disease resistance antibody, providing molecule evidences for the antibody-antigen interaction and revealing the mechanisms underlying the antibody-mediated resistance.