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.
2018-04-05 | GSE106240 | GEO
Project description:Nanopore sequencing for rapid diagnostics of salmonid RNA viruses
Project description:The Virochip microarray (version 4.0) was used to detect viruses in patients from North America with unexplained influenza-like illness at the onset of the 2009 H1N1 pandemic. We used metagenomics-based technologies (the Virochip microarray) and deep sequencing to analyze nasal swab samples from individuals with 2009 H1N1 infection. This Series includes the Virochip microarray data only.
Project description:BACKGROUND. Lower respiratory tract infection (LRTI) is a leading cause of death in children worldwide. LRTI diagnosis is challenging since non-infectious respiratory illnesses appear clinically similar and existing microbiologic tests are often falsely negative or detect incidentally-carried microbes common in children. These challenges result in antimicrobial overuse and adverse patient outcomes. Lower airway metagenomics has the potential to detect host and microbial signatures of LRTI. Whether it can be applied at scale and in a pediatric population to enable improved diagnosis and precision treatment remains unclear. METHODS. We used tracheal aspirate RNA-sequencing to profile host gene expression and respiratory microbiota in 261 children with acute respiratory failure. We developed a random forest gene expression classifier for LRTI by training on patients with an established diagnosis of LRTI (n=117) or of non-infectious respiratory failure (n=50). We then developed a classifier that integrates the: i) host LRTI probability, ii) abundance of respiratory viruses, and iii) dominance in the lung microbiome of bacteria/fungi considered pathogenic by a rules-based algorithm. RESULTS. The host classifier achieved a median AUC of 0.967 by 5-fold cross-validation, driven by activation markers of T cells, alveolar macrophages and the interferon response. The integrated classifier achieved a median AUC of 0.986 and significantly increased the confidence of patient classifications. When applied to patients with an uncertain diagnosis (n=94), the integrated classifier indicated LRTI in 52% of cases and nominated likely causal pathogens in 98% of those. CONCLUSIONS. Lower airway metagenomics enables accurate LRTI diagnosis and pathogen identification in a heterogeneous cohort of critically ill children through integration of host, pathogen, and microbiome features.