Arabidopsis ABCG34 contributes to defense against necrotrophic pathogens by mediating the secretion of camalexin

This is the authors' abstract. We don't add key points for this paper.

Significance Alternaria brassicicola infection causes dark spots on the leaves of most Brassica species, reducing the yield of economically important oilseed crops. In response to A . brassicicola infection, Arabidopsis thaliana and other Brassicaceae produce and secrete camalexin, a major phytoalexin imparting resistance to A . brassicicola . Because camalexin is toxic to the plant itself, specific transporters are needed for secretion. Here we show that the ABC transporter ABCG34 mediates the secretion of camalexin from the epidermal cells to the surface of leaves and thereby confers resistance to A . brassicicola infection. This work establishes a complete picture of a plant defense system, consisting of a toxic secondary metabolite, its transporter, and the disease phenotype caused by an economically important pathogen.