Research article - Peer-reviewed, 2020
The RsRlpA Effector Is a Protease Inhibitor Promoting Rhizoctonia solani Virulence through Suppression of the Hypersensitive Response
Charova, Spyridoula N.; Dolfors, Fredrik; Holmquist, Louise; Moschou, Panagiotis N.; Dixelius, Christina; Tzelepis, GeorgiosAbstract
Rhizoctonia solani (Rs) is a soil-borne pathogen with a broad host range. This pathogen incites a wide range of disease symptoms. Knowledge regarding its infection process is fragmented, a typical feature for basidiomycetes. In this study, we aimed at identifying potential fungal effectors and their function. From a group of 11 predicted single gene effectors, a rare lipoprotein A (RsRlpA), from a strain attacking sugar beet was analyzed. The RsRlpA gene was highly induced upon early-stage infection of sugar beet seedlings, and heterologous expression in Cercospora beticola demonstrated involvement in virulence. It was also able to suppress the hypersensitive response (HR) induced by the Avr4/Cf4 complex in transgenic Nicotiana benthamiana plants and functioned as an active protease inhibitor able to suppress Reactive Oxygen Species (ROS) burst. This effector contains a double-psi beta-barrel (DPBB) fold domain, and a conserved serine at position 120 in the DPBB fold domain was found to be crucial for HR suppression. Overall, R. solani seems to be capable of inducing an initial biotrophic stage upon infection, suppressing basal immune responses, followed by a switch to necrotrophic growth. However, regulatory mechanisms between the different lifestyles are still unknown.Keywords
basidiomycete; biotrophy; effector; cathepsin; hypersensitive response; papain inhibitor; protease; soil-borne pathogen; sugar beetPublished in
International Journal of Molecular Sciences2020, volume: 21, number: 21, article number: 8070
Authors' information
Charova, Spyridoula N.
University of Crete
Swedish University of Agricultural Sciences, Department of Plant Biology
Holmquist, Louise
MariboHilleshög Research
Foundation for Research and Technology - Hellas (FORTH)
University of Crete
Swedish University of Agricultural Sciences, Department of Plant Biology
Swedish University of Agricultural Sciences, Department of Plant Biology
Swedish University of Agricultural Sciences, Department of Forest Mycology and Plant Pathology
Associated SLU-program
SLU Network Plant Protection
UKÄ Subject classification
Agricultural Science
Publication Identifiers
DOI: https://doi.org/10.3390/ijms21218070
URI (permanent link to this page)
https://res.slu.se/id/publ/108782