The mechanism of graft transmission of sense and antisense gene silencing in tomato plants

Previous studies have shown that WRKY transcription factors play important roles in abiotic stress responses. Thus, virus-induced gene silencing (VIGS) was used to identify the function of SlWRKY79 in the salt tolerance of tomato plants by downregulating the expression of the SlWRKY79 gene. Under the same salt treatment conditions, the SlWRKY79-silenced plants showed faster stem wilting and more severe leaf shrinkage than the control plants, and the bending degree of the stem of the SlWRKY79-silenced plants was also greater than that of the control plants. Physiological analyses showed that considerably higher levels of hydrogen peroxide (H2O2), superoxide anion (O2−), and abscisic acid (ABA) accumulated in the leaves of the SlWRKY79-silenced plants than in those of the controls after salt treatment. Taken together, our results suggested that SlWRKY79 plays a positive regulatory role in salt tolerance in tomato plants.

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Host-induced gene silencing compromises Verticillium wilt in tomato and Arabidopsis

10.1101/076976 ◽

2016 ◽

Author(s):

Yin Song ◽

Bart P.H.J. Thomma

Keyword(s):

Gene Silencing ◽

Verticillium Wilt ◽

Host Plants ◽

Plant Protection ◽

Tobacco Rattle Virus ◽

Wilt Disease ◽

Tomato Plants ◽

Wide Range ◽

Soil Borne Fungi ◽

Important Disease

SUMMARYVerticillium wilt, caused by soil-borne fungi of the genus Verticillium, is an economically important disease that affects a wide range of host plants. Unfortunately, host resistance against Verticillium wilts is not available for many plant species, and the disease is notoriously difficult to combat. Host-induced gene silencing (HIGS) is an RNA interference (RNAi) based process in which small RNAs are produced by the host plant to target parasite transcripts. HIGS has emerged as a promising strategy for improving plant resistance against pathogens by silencing genes that are essential for these pathogens. Here, we assessed whether HIGS can be utilized to suppress Verticillium wilt disease by silencing previously identified virulence genes of V. dahliae through the host plants tomato and Arabidopsis. In transient assays, tomato plants were agroinfiltrated with Tobacco rattle virus (TRV) constructs to target V. dahliae transcripts. Subsequent V. dahliae inoculation revealed suppression of Verticillium wilt disease in some, but not all, cases. Next, expression of RNAi constructs targeting V. dahliae transcripts was pursued in stable transgenic Arabidopsis thaliana plants. Also in this host, V. dahliae inoculation revealed reduced Verticillium wilt disease in some cases. Thus, our study suggests that, depending on the target gene chosen, HIGS against V. dahliae is operational in tomato and A. thaliana plants and may act as a plant protection approach that may be used in Verticillium wilt-susceptible crops.

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Graft transmission of post-transcriptional gene silencing: target specificity for RNA degradation is transmissible between silenced and non-silenced plants, but not between silenced plants

The Plant Journal ◽

10.1046/j.1365-313x.2000.00645.x ◽

2000 ◽

Vol 21 (1) ◽

pp. 1-8 ◽

Cited By ~ 53

Author(s):

Shoji Sonoda ◽

Masamichi Nishiguchi

Keyword(s):

Gene Silencing ◽

Rna Degradation ◽

Transcriptional Gene Silencing ◽

Target Specificity ◽

Post Transcriptional Gene Silencing ◽

Graft Transmission

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Antisense Gene Silencing: Therapy for Neurodegenerative Disorders?

Genes ◽

10.3390/genes4030457 ◽

2013 ◽

Vol 4 (3) ◽

pp. 457-484 ◽

Cited By ~ 7

Author(s):

Troels Nielsen ◽

Jørgen Nielsen

Keyword(s):

Gene Silencing ◽

Neurodegenerative Disorders ◽

Antisense Gene

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Small RNA Profiling of Susceptible and Resistant Ty-1 Encoding Tomato Plants Upon Tomato Yellow Leaf Curl Virus Infection

Frontiers in Plant Science ◽

10.3389/fpls.2021.757165 ◽

2021 ◽

Vol 12 ◽

Author(s):

Corien M. Voorburg ◽

Yuling Bai ◽

Richard Kormelink

Keyword(s):

Gene Silencing ◽

Cytosine Methylation ◽

Tomato Yellow Leaf ◽

Transcriptional Gene Silencing ◽

Viral Gene ◽

Yellow Leaf ◽

Tomato Plants ◽

Susceptible Tomato ◽

Leaf Curl Virus ◽

Leaf Curl

Ty-1 presents an atypical dominant resistance gene that codes for an RNA-dependent RNA polymerase (RDR) of the gamma class and confers resistance to tomato yellow leaf curl virus (TYLCV) and other geminiviruses. Tomato lines bearing Ty-1 not only produce relatively higher amounts of viral small interfering (vsi)RNAs, but viral DNA also exhibits a higher amount of cytosine methylation. Whether Ty-1 specifically enhances posttranscriptional gene silencing (PTGS), leading to a degradation of RNA target molecules and primarily relying on 21–22 nucleotides (nts) siRNAs, and/or transcriptional gene silencing (TGS), leading to the methylation of cytosines within DNA target sequences and relying on 24-nts siRNAs, was unknown. In this study, small RNAs were isolated from systemically TYLCV-infected leaves of Ty-1 encoding tomato plants and susceptible tomato Moneymaker (MM) and sequence analyzed. While in susceptible tomato plants vsiRNAs of the 21-nt size class were predominant, their amount was drastically reduced in tomato containing Ty-1. The latter, instead, revealed elevated levels of vsiRNAs of the 22- and 24-nt size classes. In addition, the genomic distribution profiles of the vsiRNAs were changed in Ty-1 plants compared with those from susceptible MM. In MM three clear hotspots were seen, but these were less pronounced in Ty-1 plants, likely due to enhanced transitive silencing to neighboring viral genomic sequences. The largest increase in the amount of vsiRNAs was observed in the intergenic region and the V1 viral gene. The results suggest that Ty-1 enhances an antiviral TGS response. Whether the elevated levels of 22 nts vsiRNAs contribute to an enhanced PTGS response or an additional TGS response involving a noncanonical pathway of RNA dependent DNA methylation remains to be investigated.

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