Project description:We investigated the transcriptional response of invasive B. tabaci B biotype to tomato yellow leaf curl China virus (TYLCCNV) using Illumina sequencing technology. We found that 1,606 genes involved in 157 biochemical pathways were differentially expressed in the viruliferous whiteflies.
Project description:RNA interference (RNAi) is a widely-used approach to generate virus-resistant transgenic crops. However, durability of RNAi-mediated resistance under extreme field conditions and side-effects of stable RNAi expression have not been thoroughly investigated. Here we performed field trials and molecular characterization of two RNAi-transgenic Solanum lycopersicum lines resistant to Tomato yellow leaf curl virus (TYLCV) disease, the major constraint for tomato cultivation in Cuba and worldwide. In order to determine potential impact of the hairpin RNA transgene expression on tomato genome expression and development, differences in the phenotypes and the transcriptome profiles between the transgenic and non-transgenic plants were examined. Transcriptome profiling revealed a common set of up- and down-regulated tomato genes, which correlated with slight developmental abnormalities in both transgenic lines.
Project description:We investigated the transcriptional response of invasive B. tabaci B biotype to tomato yellow leaf curl China virus (TYLCCNV) using Illumina sequencing technology. We found that 1,606 genes involved in 157 biochemical pathways were differentially expressed in the viruliferous whiteflies. Culture of B biotype whitefly was maintained on cotton plants. Three thousands of newly emerged adults of whitefly on cotton were released onto the leaves of healthy and viruliferous tobacco plants. They were allowed to feed for 24 h. After that, non-viruliferous and viruliferous whiteflies were transferred respectively to cotton plants in different cages and allowed to feed for 120 h. Then approximately 1,000 non-viruliferous and viruliferous female adults of whitefly were collected, respectively. The RNA was extracted and sequenced using Illunima Analyzer II.
Project description:The whitefly, Bemisia tabaci MEAM1 is a devastating vector capable of transmitting hundreds of plant viruses, including Tomato yellow leaf curl virus (TYLCV), to important food and fiber crops. Here we performed genome-wide profiling of micro RNAs (miRNAs) and piwi-interacting RNAs (piRNAs) in whiteflies after feeding on TYLCV-infected tomato or uninfected tomato for 24, 48 and 72 h. Overall, 160 miRNAs were discovered, 68 of which were conserved and 92 were B. tabaci-specific miRNAs. Majority of the genes that were predicted to be targeted by miRNAs had gene ontologies related to metabolic processes. We identified two miRNAs that were differentially expressed in whiteflies when fed on TYLCV-infected tomato compared to whiteflies that fed on uninfected tomato. The identified piRNAs were expressed as clusters throughout the whitefly genome. A total of 53 piRNA clusters were expressed across all time points and treatments, while 5 piRNA clusters were exclusively expressed in whiteflies that fed on TYLCV-infected tomato, and 24 clusters were exclusively expressed in whiteflies that fed on uninfected tomato. Approximately 62% of all identified piRNAs were derived from non-coding sequences that included intergenic regions, introns, and UTRs with unknown functions. The remaining 38% of piRNAs were derived from coding sequences (CDS) and repeat elements. Transposable elements targeted by piRNA clusters included both class I retrotransposons such as Gypsy, Copia, and LINEs and class II DNA transposons such as MITE, hAT, and TcMar. Lastly, six protein coding genes were targeted in whiteflies that fed on TYLCV-infected tomato. Information on how TYLCV influences miRNA and piRNA expression in whiteflies provides a greater understanding of regulatory pathways involved in mediating whitefly-virus interactions, and will facilitate the identification of novel targets for RNAi control.
Project description:A comparative study to determine the pepper leaf curl virus resistance machanism between resistant and susceptible genotypes at three leaf stage. To study the molecular mechanism of pepper leaf curl virus (PepLCV) resistance, pepper plants were exposed to PepLCV through artificial inoculation and hybridization on Agilent tomato microarrays. The expression analysis of PepLCV resistant and susceptible genotypes after artificial inoculation at three leaf stage showed that the resistance against PepLCV is due to sum of expression of hundreds of genes at a particular stage.
