Arsenal of elevated defense proteins fails to protect tomato against Verticillium dahliae

Abstract

Although the hypersensitive reaction in foliar plant diseases has been extensively described, little is clear regarding plant defense strategies in vascular wilt diseases affecting numerous economically important crops and trees. We have examined global genetic responses to Verticillium wilt in tomato (Lycopersicon esculentum Mill.) plants differing in Ve1 resistance alleles. Unexpectedly, mRNA analyses in the susceptible plant (Ve1-) based on the microarrays revealed a very heroic but unsuccessful systemic response involving many known plant defense genes. In contrast, the response is surprisingly low in plants expressing the Ve1+ R-gene and successfully resisting the pathogen. Similarly, whole-cell protein analyses, based on 2D gel electrophoresis and mass spectrometry, demonstrate large systemic increases in a variety of known plant defense proteins in the stems of susceptible plants but only modest changes in the resistant plant. Taken together, the results indicate that the large systemic increases in plant defense proteins do not protect the susceptible plant. Indeed, since a number of the highly elevated proteins are known to participate in the plant hypersensitive response as well as natural senescence, the results suggest that some or all of the disease symptoms, including ultimate plant death, actually may be the result of this exaggerated plant response.

Proteomics-based analysis reveals that Verticillium dahliae toxin induces cell death by modifying the synthesis of host proteins

“…3d, a deepbrown polymerization product was clearly seen in cotton roots 72 h after V. dahliae inoculation, but was absent in control plants (Fig. 3c), indication that cotton generated ROS, as the so-called oxidative burst, after infection with V. dahliae, consistent with the results of Robb et al (2012).…”

“…The fungus thus seems to regulate host protein synthesis to successfully infect cotton. Robb et al (2012) considered that Verticillium wilt actually may be the result of an exaggerated plant response induced by V. dahliae. Based on the present results, however, toxins play a crucial role of Verticillium wilt, but the effective molecule or effectors in the toxins remain a scientific puzzle.…”

Evaluation of Reference Genes for RT-qPCR Expression Studies in Hop (Humulus lupulus L.) during Infection with Vascular Pathogen Verticillium albo-atrum

“…Wye Target, which responded to stress only at 20 dpi. Higher induction of defense genes in susceptible than in resistant plants on infection with vascular wilt diseases such as Verticillium wilt has been previously reported [31].…”

Large-scale transcriptome comparison of sunflower genes responsive to Verticillium dahliae

“…Each seedling was inoculated with 50 mL of V. dahliae spore suspension with 2 × 10 6 spores/ml at the two-true-leaf growth stage [54]. Control plants were not inoculated but were treated and sampled with distilled water in the same manner.…”