Disruption of the methionine cycle and reduced cellular gluthathione levels underlie potex-potyvirus synergism in Nicotiana benthamiana

Show full item record



Permalink

http://hdl.handle.net/10138/298271

Citation

De , S , Chavez-Calvillo , G , Wahlsten , M & Mäkinen , K 2018 , ' Disruption of the methionine cycle and reduced cellular gluthathione levels underlie potex-potyvirus synergism in Nicotiana benthamiana ' , Molecular Plant Pathology , vol. 19 , no. 8 , pp. 1820-1835 . https://doi.org/10.1111/mpp.12661

Title: Disruption of the methionine cycle and reduced cellular gluthathione levels underlie potex-potyvirus synergism in Nicotiana benthamiana
Author: De, Swarnalok; Chavez-Calvillo, Gabriela; Wahlsten, Matti; Mäkinen, Kristiina
Contributor: University of Helsinki, Plant-Virus Interactions
University of Helsinki, Department of Microbiology
University of Helsinki, Department of Microbiology
Date: 2018-08
Language: eng
Number of pages: 16
Belongs to series: Molecular Plant Pathology
ISSN: 1464-6722
URI: http://hdl.handle.net/10138/298271
Abstract: Infection caused by the synergistic interaction of two plant viruses is typically manifested by severe symptoms and increased accumulation of either virus. In potex-potyviral synergism, the potyviral RNA silencing suppressor helper component proteinase (HCPro) is known to enhance the pathogenicity of the potexvirus counterpart. In line with this, Potato virus X (PVX; genus Potexvirus) genomic RNA (gRNA) accumulation and gene expression from subgenomic RNA (sgRNA) are increased in Nicotiana benthamiana by Potato virus A (PVA; genus Potyvirus) HCPro expression. Recently, we have demonstrated that PVA HCPro interferes with the host cell methionine cycle by interacting with its key enzymes S-adenosyl-l-methionine synthetase (SAMS) and S-adenosyl-l-homocysteine hydrolase (SAHH). To study the involvement of methionine cycle enzymes in PVX infection, we knocked down SAMS and SAHH. Increased PVX sgRNA expression between 3 and 9 days post-infiltration (dpi) and upregulation of (-)-strand gRNA accumulation at 9 dpi were observed in the SAHH-silenced background. We found that SAMS and SAHH silencing also caused a significant reduction in glutathione (GSH) concentration, specifically in PVX-infected plants between 2 and 9 dpi. Interestingly, HCPro expression in PVX-infected plants caused an even stronger reduction in GSH levels than did SAMS+SAHH silencing and a similar level of reduction was also achieved by knocking down GSH synthetase. PVX sgRNA expression was increased in the GSH synthetase-silenced background. GSH is a major antioxidant of plant cells and therefore GSH shortage may explain the strong oxidative stress and severe symptoms observed during potex-potyvirus mixed infection.
Subject: glutathione
HCPro
methionine cycle
potexvirus
potyvirus
S-adenosyl-l-homocysteine hydrolase
silencing suppressor
POTATO-VIRUS-X
CUCURBITA-PEPO L.
MOSAIC-VIRUS
PLANT-VIRUSES
HC-PRO
COAT PROTEIN
INFECTION
RNA
SUPPRESSION
REPLICATION
1183 Plant biology, microbiology, virology
Rights:


Files in this item

Total number of downloads: Loading...

Files Size Format View
De_et_al_2017_submitted.pdf 2.340Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record