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Title: The tomato Arp2/3 complex is required for resistance to the powdery mildew fungus Oidium neolycopersici
Abstract

The actin‐related protein 2/3 complex (Arp2/3 complex), a key regulator of actin cytoskeletal dynamics, has been linked to multiple cellular processes, including those associated with response to stress. Herein, theSolanum habrochaitesARPC3gene, encoding a subunit protein of the Arp2/3 complex, was identified and characterized.ShARPC3encodes a 174‐amino acid protein possessing a conserved P21‐Arc domain. Silencing ofShARPC3resulted in enhanced susceptibility to the powdery mildew pathogenOidium neolycopersici(On‐Lz), demonstrating a role forShARPC3in defence signalling. Interestingly, a loss ofShARPC3coincided with enhanced susceptibility toOn‐Lz, a process that we hypothesize is the result of a block in the activity of SA‐mediated defence signalling. Conversely, overexpression ofShARPC3inArabidopsis thaliana, followed by inoculation withOn‐Lz, showed enhanced resistance, including the rapid induction of hypersensitive cell death and the generation of reactive oxygen. Heterologous expression ofShARPC3in thearc18mutant ofSaccharomyces cerevisiae(i.e.,∆arc18) resulted in complementation of stress‐induced phenotypes, including high‐temperature tolerance. Taken together, these data support a role for ShARPC3 in tomato through positive regulation of plant immunity in response toOneolycopersicipathogenesis.

 
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NSF-PAR ID:
10461073
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Plant, Cell & Environment
Volume:
42
Issue:
9
ISSN:
0140-7791
Page Range / eLocation ID:
p. 2664-2680
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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