Hibiscus chlorotic ringspot virus Coat Protein Upregulates Sulfur Metabolism Genes for Enhanced Pathogen Defense

Abstract

In both Hibiscus chlorotic ringspot virus (HCRSV)-infected and HCRSV coat protein (CP) agroinfiltrated plant leaves, we showed that sulfur metabolism pathway related genes-namely, sulfite oxidase (SO), sulfite reductase, and adenosine 5'-phosphosulfate kinase-were upregulated. It led us to examine a plausible relationship between sulfur-enhanced resistance (SED) and HCRSV infection. We broadened an established method to include different concentrations of sulfur (0S, 1S, 2S, and 3S) to correlate them to symptom development of HCRSV-infected plants. We treated plants with glutathione and its inhibitor to verify the SED effect. Disease resistance was induced through elevated glutathione contents during HCRSV infection. The upregulation of SO was related to suppression of symptom development induced by sulfur treatment. In this study, we established that HCRSV-CP interacts with SO which, in turn, triggers SED and leads to enhanced plant resistance. Thus, we have discovered a new function of SO in the SED pathway. This is the first report to demonstrate that the interaction of a viral protein and host protein trigger SED in plants. It will be interesting if such interaction applies generally to other host-pathogen interactions that will lead to enhanced pathogen defense.

Plant Growth Retardation and Conserved miRNAs Are Correlated to Hibiscus Chlorotic Ringspot Virus Infection

“…Other symptoms include mosaic patterns, rings, vein-clearing and vein-banding [6]. Regarding the host-virus interaction, HCRSV coat protein (HCRSV-CP) interacts with sulfite oxidase (SO) [7] which in turn, triggers sulfur enhanced defense (SED) and leads to enhanced plant resistance [8]. …”

Multiple functions of capsid proteins in (+) stranded RNA viruses during plant–virus interactions

“…Viral infection can boost metabolic genes for enhanced anti-viral defense via CP contribution. For instance, the Hibiscus chlorotic ringspot carmovirus (HCRSV) CP upregulates sulfur metabolism genes in the infected kenaf plants (Gao et al, 2012). By treating plants with glutathione and its inhibitor, the disease resistance was induced during HCRSV infection.…”

Analyses of RNA-Seq and sRNA-Seq data reveal a complex network of anti-viral defense in TCV-infected Arabidopsis thaliana

“…Cold protein extraction buffer54 was added into the powder proportionally. The cell debris was removed by centrifuging samples at 12,000 ×  g for 20 min at 4 °C.…”