FUNCTIONAL GENOMICS OF CEREAL DISEASE DEFENSE
Location: Corn Insects and Crop Genetics Research
Title: Regulators of Innate Immunity in Cereal-fungal Interactions
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: February 22, 2010
Publication Date: May 1, 2010
Citation: Wise, R.P., Meng, Y., Moscou, M.J., Xu, W. 2010. Regulators of Innate Immunity in Cereal-fungal Interactions. In: Antoun, H., Avis, T., Brisson, L., Prevost, D., Trepanier, M., editors. Biology of Plant-Microbe Interactions. St. Paul, MN: International Society for Molecular Plant-Microbe Interactions. p. 1-7.
The plant immune system plays a crucial role in preventing microbial invasion and growth. PAMPs (pathogen-associated molecular patterns) are presented by diverse pathogens, and trigger the activation of non-specific basal defense mechanisms. These responses include the transcription of thousands of stress-related genes, as well as the induction of antimicrobial metabolites and peptides during early stages of pathogen invasion. By contrast, effector-triggered immunity (ETI) is driven by gene-for-gene interactions, where a specific resistance (R) protein initiates a signal cascade when it recognizes, either directly or indirectly, its corresponding Avirulence (AVR) effector delivered by an invading pathogen. We recently characterized a new monocot-specific family of small cysteine-rich peptides, designated blufensins, which negatively impact plant defense. BLUFENSIN1 (BLN1) is highly induced during fungal infection, is predicted to be secreted, and contains both structural and sequence similarities to knottins, small disulfide-rich proteins characterized by a unique "disulfide through disulfide knot." It is possible that Bln1, as a negative regulator of basal defense, could be a plant equivalent of mammalian chemokine receptors. Hence, interactors or partners of BLN1 would be expected to play key roles in mediating the plant immune response. Here, we report our characterization of several genes in the secretory pathway impacted by the Bln1 regulatory gene and their influence on plant defense. Because common themes govern all plant-pathogen interactions, these findings provide new knowledge of broad significance to plant scientists, and to growers who utilize disease resistance to protect their crops.