Proteomic analysis of the proteins secreted by the infection cushions of Botrytis cinerea.

Gray mold disease affects fruits, vegetables and ornemental plants around the world, causing considerable losses every year. Its causing agent, the fungus Botrytis cinerea, produces infection cushions (IC) that are complex appressorial structure dedicated to the penetration of the plant tissues. A microarray analysis identified 1,231 up-regulated genes in IC-enriched mycelium, among which several genes coding for putative secreted proteins. These data were supported by qPCR analysis in vitro and in planta. They highlight a secretion of proteins involved in virulence like proteases, plant cell wall degrading enzymes and necrosis inducers. To validate these transcriptomic data, a proteomic analysis of the IC exo-proteome is required.