Comparative Analysis of the Expression Profiles of Pathogenesis-Related Genes in Tomato Systemically Infected with Tobacco Mosaic and Cucumber Mosaic Viruses

Abstract

In this study, we used RT-qPCR to examine how PR genes were expressed in model tomato (Solanum lycopersicum L.) plants that had been infected with TMV or CMV. Under greenhouse conditions, the indirect ELISA data showed that both viruses were detected for the first time at 6 dpi. Then, the levels of accumulation increased very quickly, reaching a peak of 15 dpi. During the course of the study (1–15 dpi), the Delta CT, NormFinder, BestKeeper, and GeNorm software tools revealed that the β-actin gene was the most informative reference gene in the virally infected tomato tissues. For both the TMV- and CMV-infected tomato plants, the transcriptional expression levels of most tested genes changed between activation and repression, especially in the first 12 dpi. Compared to mock-inoculated plants, the expression levels of PR-1 were induced at all time intervals except at 8 dpi for CMV and at 6, 7, and 8 dpi for TMV infection. Conversely, the greater activation and accumulation of both viruses were associated with the greater up-regulation of PR-2 at 8 dpi, with relative expression levels of 7.28- and 5.84-fold for TMV and CMV, respectively. The up-regulated expression of PR-3, PR-4, and PR-7 was shown at 4 dpi. In contrast, the PR-5 gene was inhibited in TMV at 1 dpi until 9 dpi, and the induction of this gene at 10 dpi increased by 1.72-fold, but PR-5 was observed to up-regulate the expression of CMV at 1 dpi. This study provides the first valuable information on the comparative transcriptional levels of these tomato genes between TMV and CMV infections.

Transcriptional responses and secondary metabolites variation of tomato plant in response to tobacco mosaic virus infestation

“…These changes result in cell damage, the generation of reactive oxidant species (ROS), and the initiation of pathogen-triggered defensive responses 18 . Biochemical defense processes including PRs proteins, phenylalanine ammonia-lyase (PAL), and ROS improve plant defense by producing secondary bioactive compounds 19 . Moreover, the viral infection was discovered to affect the host's gene expression pattern and responses, with gene silencing possibly associated with antiviral systems 4 .…”

Carboxypeptidase inhibitors from Solanaceae as a new subclass of pathogenesis related peptide aiming biotechnological targets for plant defense

“…citri ( Conti et al, 2020 ). In tomato, PR protein expression genes are associated with defense against insects such as Trialeurodes vaporariorum and Bemisia tabaci , as well as viruses like Tobacco mosaic virus and Cucumber mosaic virus ( Puthoff et al, 2010 ; Aseel et al, 2023 ). These findings underscore the significance of PR proteins in plant defense mechanisms, particularly in the context of Solanaceae plants.…”