Tomato constitutes a primary agricultural industry, but its production is severely impaired by Phytophthora infestans (P. infestans). Although identifying numerous resistance genes, the molecular mechanisms underlying tomato resistance to P. infestans remain elusive. Here, we identified SlPep, a plant elicitor peptide that confers resistance to P. infestans in tomato. SlPep originates from the C terminus of the precursor protein, SlPROPEP, in tomato. The expression of SlPROPEP was transcriptionally induced upon P. infestans infection. And, transiently overexpressing of SlPROPEP enhanced tomato resistance by elevating the levels of reactive oxygen species and pathogenesis-related genes, whereas silencing of SlPR... More
Tomato constitutes a primary agricultural industry, but its production is severely impaired by Phytophthora infestans (P. infestans). Although identifying numerous resistance genes, the molecular mechanisms underlying tomato resistance to P. infestans remain elusive. Here, we identified SlPep, a plant elicitor peptide that confers resistance to P. infestans in tomato. SlPep originates from the C terminus of the precursor protein, SlPROPEP, in tomato. The expression of SlPROPEP was transcriptionally induced upon P. infestans infection. And, transiently overexpressing of SlPROPEP enhanced tomato resistance by elevating the levels of reactive oxygen species and pathogenesis-related genes, whereas silencing of SlPROPEP impaired resistance. Moreover, we demonstrated that SlWRKY6 could enhance tomato resistance via up-regulating the expression of SlPROPEP. Additionally, we observed that the exogenous application of SlPep promoted jasmonic acid and ethylene contents, inducing tomato resistance towards P. infestans. Overall, our findings shed light on the molecular roles of the SlWRKY6-SlPROPEP-SlPep module in tomato-P. infestans interactions, providing novel insights into horticultural crop improvement.