Louis Bengyella
Vaal University of Technology, South Africa
Title: Proteomics insight into temperature-dependent pathogenicity of Cochliobolus lunatus during invasion of potato
Biography
Biography: Louis Bengyella
Abstract
It is established that Cochliobolus lunatus secretes a myriad of proteins to break plant primary defense (i.e. cuticle and cell walls) and degrade complex carbohydrates for nutrients acquisition. Many larger secreted proteins with potential roles in pathogenicity include predicted cutinases, peptidases, glucanases, fungal transporters belonging to the major facilitator super-family (MFS), and ATP-binding cassette (ABC) group proteins, and carbohydrates active enzymes. But major physiological pathways affected in potato during C. lunatus colonization are unknown during incitement of brown-to-black leaf spot disease. Using proteomics approach, it is shown that C. lunatus significantly (P<0.05) suppressed the host functional proteome at 96 h after infection, predominantly affecting the expression of ribulose bisphosphate carboxylase enzyme, plastid aldolase enzyme, alcohol dehydrogenase 2 and photosystem II protein prior to the formation of brown-to-black leaf spot disease. Robust host–response was observed at 24 h after infection associated by 307 differentially expressed peptide spots concurring with the active phase of production of infectious hyphae. Importantly, C. lunatus differentially down-regulate StNPR1 transcript by 8.19-fold by 24 h after infection. We also observed that C. lunatus transiently down-regulate the expression of StNPR1 at the onset of infection. Put together, the infection negatively affects the expression of proteome modules involved in photosynthesis, carbon fixation and light assimilation. This study contributes towards better understanding of the mechanism underlining the invasion strategies of C. lunatus.