Towards synthetic disease resistance genes

GIANNAKOPOULOU, ARTEMIS; PAIS, MARINA; CHAPARRO GARCÍA, ANGELA; SEGRETIN, MARÍA EUGENIA; KAMOUN, SOPHIEN

Rodas

Congreso; XVI International Congress on Molecular Plant-Microbe Interactions; 2014

IS-MPMI

Plants and pathogens are engaged in a co-evolutionary arms race, in which plants deploy various defense mechanisms and pathogens develop ways to modulate host processes and immunity. An important component of the plant defense machinery involves intracellular immunoreceptors of the nucleotide-binding leucine-rich repeat-containing protein family (NBLRR). NB-LRRs typically recognize pathogen effector proteins with avirulent activities, and activate a response known as NB-LRR-triggered immunity (NTI). R3a and I2 are orthologous NB-LRRs from potato and tomato that recognize effectors of the late blight oomycete pathogen Phytophthora infestans and the wilt causing ascomycete Fusarium oxysporum f. sp. lycopersici (FOL) respectively. However, particular races of these pathogens have evolved stealthy effectors that evade recognition by R3a and I2. Our goal is to create synthetic NBLRR mutants with expanded pathogen recognition specificities to develop broad-spectrum solutions to important plant pathogens. In a previous study we identified 8 single-residue mutations in the R3a protein that conferred expanded response to Phytophthora sp. effectors. We investigated whether these mutations alter the response profile of I2, and recovered I2 mutants with expanded spectrum of effector response from diverse pathogens. We are currently evaluating whether this expanded response correlates with a broader resistance spectrum using both transient and stable transgenic systems. These results could lead to new insights into the molecular interactions underlying pathogen perception by plants, building up our knowledge on basic and applied plant pathology.