Project description:Several pathogens infect grapevine, including viruses and viroids. Considering that there are no effective plant protection treatments against these pathogens and vineyards are cultivated through decades usage of high quality and pathogen-free propagation material (rootstocks and scions) is essential. Although presence of regulated pests is routinely checked using ELISA or rarely RT-PCR, these diagnostics methods can detect only particular pathogens moreover can fail to detect variant strains. High-throughput sequencing of small RNAs can be an effective, alternative method to avoid these disadvantages. Since for production of grafts, pathogen free cultivars and rootstocks must be used, 17 grapevine rootstock plantations and 2 rootstock variety collections were selected for characterisation of their virom by high throughput sequencing of virus derived small RNAs.
Project description:Meristem culture and somatic embryogenesis is an effective tool for virus elimination of vegetatively propagated crops including grapevine. While they both are proved to be useful to eliminate the main grapevine viruses their efficiency differs according to the virus and the variety. In our work we investigated their efficiency using small RNA high-throughput sequencing as virus diagnostic method. Field grown mother plants of four clones representing three cultivars, infected with different viruses and viroids were selected for sanitation via somatic embryogenesis and meristem culture. Our results show that the sanitation with SE was efficient against all of the presenting viruses, including grapevine Pinot gris virus, grapevine rupestris vein feathering virus and grapevine Syrah virus 1, having no data using somatic embryogenesis for their elimination. In case of other viruses and viroids such as GFkV, GRSPaV, GYSVd-1, HSVd this study confirms the findings of earlier researches, that SE is a possible way for elimination. While the efficiency of the elimination of different viruses was high, in case of viroids this ratio was lower. Our work demonstrated that efficiency of SE is comparable to the technically difficult meristem culture technique, and show promising way for the high demand of the production of virus-free grapevine in the future.
Project description:As virus diseases cannot be controlled by traditional plant protection methods the risk of their spread have to be minimized on vegetatively propagated plants, such as grapevine. Metagenomics approaches used for virus diagnostics, offer a unique opportunity to reveal the presence of all viral pathogens in the investigated plant, why their usage can reduce the risk of using infected material for a new plantation. Here we used a special field, deep sequencing of virus derived small RNAs, of this high throughput method for virus diagnostics and determined viromes of vineyards in Hungary. With NGS of virus derived small RNAs we could detect not only the viruses tested routinely, but also new ones, which have never been described in Hungary before. Virus presence didn’t correlated with the age of the plantation, moreover phylogenetic analysis of the identified virus isolates suggests that infections mostly caused by the usage of infected propagating material. Our results, validated by other molecular methods, highlighted further questions to be answered before these method can be introduced as a routine, reliable test for grapevine virus diagnostics.
Project description:In order to analyze the production of small RNA (sRNA) by viroids upon infecting the plants, the tomato plants (Lycopersicum esculentum cv. Rutgers) were inoculated with the variants of Potato spindle tuber viroid (PSTVd). After 21-days of post inoculation, total RNA was extracted and subjected for deep-sequencing using Illumina platform. The primers were trimmed and only 21- to 24-nt long small RNAs were filtered after quality check of the raw data. The filtered 21- to 24-nt was mapped against the genomic and antigenomic strands of the respective PSTVd variants using standard pattern matching algorithm. The profiling of viroid derived sRNA (vd-sRNA) revealed that the viroids are susceptible to host RNA silencing mechanism. Evaluation of the vd-sRNA production in PSTVd infected tomato plants by high-throughput sequencing of small RNAs.
Project description:Implementation and evaluation of tests (PCR, ELISA, NGS) for the presence of viruses, viroids and phytoplasma in propagation materials of apple. Research and application of new sanitation techniques using promising antiviral substances, or cryo-knife. Confirmation of health status of sanitated cultivars including use of modern diagnostic methods such as high-throughput sequencing (NGS).
Project description:MicroRNAs (miRNAs) are a class of non-coding RNA molecules which have significant gene regulation roles in organisms. The advent of new high throughput sequencing technologies has enabled the revelation of novel miRNAs. Although there are two recent reports on high throughput sequencing analysis of small RNA libraries from different organs of two grapevine wine varieties, there were significant divergence in the number and kinds of miRNAs sequenced in these studies. More sequencing of small RNA libraries is still important for the discovery of novel miRNAs in grapevine. Here, we initially constructed a small RNA library of flower and fruit tissues of a table grapevine cultivar M-bM-^@M-^XSummer BlackM-bM-^@M-^Y and performed sequencing and analysis of sRNAs using the Illumina Solexa platform, expecting to discover more miRNAs related to the development of grapevine flowers and berries and the formation of dessert quality in grapevine berries. Totally, 130 conserved grapevine miRNA (Vv-miRNA) belonging to 28 Vv-miRNA families were validated, and 92 novel potential grapevine-specific ones representing 80 unique ones were first discovered. Forty-two (48.84%) of the novel miRNAs possessed differential semi-quantitative PCR expression profiles in various grapevine tissues that could further confirm their existence in the grapevine, among which twenty were expressed only in grapevine berries, indicating some fruit-specificity. 130 target genes for 46 novel miRNAs could be predicted. The locations of these potential target genes on grapevine chromosomes and their complementary levels with the corresponding miRNAs were also analyzed. Size fractionated small RNAs (16-30 bp) from total RNA extracts was ligated to 5' and 3' adapters, and reverse transcribed. After PCR amplification the sample was subjected to Solexa sequencing. The resultant 35nt sequence data were filtered according to base quality value. The remained sequences were used to trim 5' and 3' adaptors. The clean tags were used for further analysis.
Project description:As important roles of small RNA pathways, AGO proteins mediate interaction of incorporated small RNAs with their targets. The resolution of AGO associated small RNAs showed a significant landscape of AGO proteins and their binding small RNAs. To characterize small RNAs that associated with BmAGO2 protein in Bombyx mori, the small RNA population associated with BmAGO2 in BmN cells was extracted from the AGO immunoprecipitated complex and the small RNAs between 17nt to 50nt separated by a polyacrylamide gel electrophoresis were subjected to library construction and deep sequencing.The high throughput sequencing yielded a total of 11691441 reads, representing 813,702 unique reads with a abundance from 5731905 to 1. Small RNA associated with AGO2 of BmN cell infected with ie1-bacmid recombinant viruses were performed by high-throughput using Hiseq 2000.
Project description:MicroRNAs (miRNAs) are a class of non-coding RNA molecules which have significant gene regulation roles in organisms. The advent of new high throughput sequencing technologies has enabled the revelation of novel miRNAs. Although there are two recent reports on high throughput sequencing analysis of small RNA libraries from different organs of two grapevine wine varieties, there were significant divergence in the number and kinds of miRNAs sequenced in these studies. More sequencing of small RNA libraries is still important for the discovery of novel miRNAs in grapevine. Here, we initially constructed a small RNA library of flower and fruit tissues of a table grapevine cultivar ‘Summer Black’ and performed sequencing and analysis of sRNAs using the Illumina Solexa platform, expecting to discover more miRNAs related to the development of grapevine flowers and berries and the formation of dessert quality in grapevine berries. Totally, 130 conserved grapevine miRNA (Vv-miRNA) belonging to 28 Vv-miRNA families were validated, and 92 novel potential grapevine-specific ones representing 80 unique ones were first discovered. Forty-two (48.84%) of the novel miRNAs possessed differential semi-quantitative PCR expression profiles in various grapevine tissues that could further confirm their existence in the grapevine, among which twenty were expressed only in grapevine berries, indicating some fruit-specificity. 130 target genes for 46 novel miRNAs could be predicted. The locations of these potential target genes on grapevine chromosomes and their complementary levels with the corresponding miRNAs were also analyzed.
Project description:Background: MicroRNAs (miRNAs) are a class of single-stranded non-coding small RNAs (sRNAs) that are 20-24 nucleotides (nt) in length. Extensive studies have indicated that miRNAs play important roles in plant growth, development, and stress responses. With more copper (Cu) and copper-containing compounds used as bactericides and fungicides in viticulture, Cu stress has become one of the serious environmental problems that affect plant growth and development. In order to uncover the hidden response mechanisms of Cu stress, many Cu-responsive miRNAs have been detected in several plant species. However, there have been few reports about the grapevine miRNAs in response to Cu. Results: Here, two small RNA libraries were constructed from Cu-treated and water-treated (control) leaves of 'Summer Black' grapevine. Following high-throughput sequencing and filtering, 158 known vvi-miRNAs and 98 novel vvi-miRNAs were identified in the two libraries. Among these, 24 could only be detected in the treatment, and 63 were only detected in the control. Additionally, 100 known vvi-miRNAs were found to be clearly responsive to Cu, among which 96 were down-regulated and four were up-regulated; 47 novel vvi-miRNAs were found to be clearly responsive to Cu, among which 35 were down-regulated and 12 were up-regulated. Subsequently, expression patterns of a set of Cu-responsive vvi-miRNAs were validated by quantitative real-time PCR (qRT-PCR). There existed some consistency in expression levels of Cu-responsive vvi-miRNAs between high-throughput sequencing and qRT-PCR assays. In addition, 92 putative targets for 79 known vvi-miRNAs and 51 putative targets for 22 novel vvi-miRNAs were predicted, and most of the targets are involved in multiple biological processes including transcriptional regulation and response to biotic and abiotic stresses. Conclusions: In this study, 147 Cu-responsive vvi-miRNAs were identified using high-throughput sequencing, and their target genes were predicted, which will be helpful to understanding the molecular mechanisms of miRNAs in response to Cu stress. Furthermore, this work can also provide a foundation for further study of the networks of miRNAs involved in grapevine plant growth and breeding some Cu-tolerant grapevine cultivars. Mixed 'Summer Black' grapevine young leaves (2 weeks old), large leaves (5 weeks old), and old leaves (9 week old) in randomly-selected plants from both the Cu-treated and control groups were collected for high-throughput sequencing. Subsequently, we carried out the analysis of Solexa sequencing data, and performed the research of regulatory modes of grapevine miRNAs on their target genes during Cu stress.