The fungal subtilase AsES elicits a PTI‐like defence response in Arabidopsis thaliana plants independently of its enzymatic activity. (26th November 2019)

• Record Type: Journal Article
• Authors: Caro, María del Pilar; Holton, Nicholas; Conti, Gabriela; Venturuzzi, Andrea Laura; Martínez‐Zamora, Martin Gustavo; Zipfel, Cyril; Asurmendi, Sebastian; Díaz‐Ricci, Juan Carlos
• Is Part Of: Molecular plant pathology. Volume 21:Number 2(2020)
• Page Start: 147
• Page End: 159
• Publication Date: 2019-11-26
• Subjects: enzymatic activity -- eliciting activity -- plant defence -- PAMP -- subtilase; Plant diseases -- Molecular aspects -- Periodicals; Plant-pathogen relationships -- Molecular aspects -- Periodicals; 571.936
• DOI: 10.1111/mpp.12881
• Languages: English
• ISSNs: 1464-6722

Abstract

Summary: Acremonium strictum elicitor subtilisin (AsES) is a 34‐kDa serine‐protease secreted by the strawberry fungal pathogen A. strictum. On AsES perception, a set of defence reactions is induced, both locally and systemically, in a wide variety of plant species and against pathogens of alternative lifestyles. However, it is not clear whether AsES proteolytic activity is required for triggering a defence response or if the protein itself acts as an elicitor. To investigate the necessity of the protease activity to activate the defence response, AsES coding sequences of the wild‐type gene and a mutant on the active site (S226A) were cloned and expressed in Escherichia coli . Our data show that pretreatment of Arabidopsis plants with inactive proteins, i.e. inhibited with phenylmethylsulphonyl fluoride (PMSF) and mutant, resulted in an increased systemic resistance to Botrytis cinerea and expression of defence‐related genes in a temporal manner that mimics the effect already reported for the native AsES protein. The data presented in this study indicate that the defence‐eliciting property exhibited by AsES is not associated with its proteolytic activity. Moreover, the enhanced expression of some immune marker genes, seedling growth inhibition and the involvement of the co‐receptor BAK1 observed in plants treated with AsES suggests that AsES is being recognized as a pathogen‐associated molecular pattern by a leucine‐rich repeat receptor. The understanding of the mechanism of action of AsES will contribute to the development of new breeding strategies to confer durable resistance in plants.