Project description:A dissection of Genotype x Environment interactions in grapevine berry using a multi-layered -omics approach Grapevine, the most widely-cultivated perennial fruit crop, is also considered a very environmentally sensitive crop. It is characterized by remarkable phenotypic plasticity which in turn is believed to effectively buffer environmental extremes especially through transcriptomic and epigenomic reprogramming. Thus, the final phenotype (P) of a given vine is the result of the close interaction between its genetic composition (G) and the environment (E). Here we analyzed Genotype x Environment (GxE) interactions in two grapevine varieties by characterizing their transcriptome plasticity when cultivated in different environments. Specifically, two genotypes (Sangiovese and Cabernet Sauvignon) were cultivated in three different locations in Italy (Bolgheri -littoral Tuscany-, Montalcino – Appennine Tuscany- and Romagna -foothill area-), trained in an almost identical manner, and sampled at four developmental stages over two grapevine growing seasons, 2011 and 2012, for a total of 144 samples that were analyzed by hybridization to a whole-genome microarray and by Reduced Representation Bisulfite Sequencing (RRBS-seq). In order to study the relationships among differential gene expression profiles and environmental cues, we have developed a new statistical data mining tool based on data reduction approaches which allowed a dissection of the transcriptomic data into stage-specific, cultivar-related and GxE important clusters of gene expression. This deep inspection of inner relationships between the different dataset variables allowed the identification of several candidate genes that could represent putative markers of berry quality traits in grapevine GxE interactions. Moreover, the methods used to establish our model provide a framework for the analysis of transcriptome plasticity in other crops as they respond to diverse environments.
Project description:RAW264.7 cells were untreated or treated with CpG+/-Gf for 6 hours. Total RNA was analyzed via Illumina Mouse Ref-8 V2. CpG‐induced genes and their regulation by Gf were examined.
Project description:Grapevine red blotch is a recently identified viral disease that was first recognized in the Napa Valley of California. Infected plants showed foliar symptoms similar to leafroll, another grapevine viral disease, on vines testing negative for known grapevine leafroll-associated virus. Later, the Grapevine red blotch virus (GRBV) was independently discovered in the US states of California and New York and was demonstrated to be the causal agent of red blotch disease. Due to its wide occurrence in the US, vector transmission and impacts on grape industry, this virus has the potential to cause serious economic losses. Despite numerous attempts, it was not possible to isolate or visualize viral particles from GRBV infected plants. Consequently, this has hampered the development of a serological assay that would facilitate GRBV detection in grapevine. We therefore decided to explore mass spectrometry approaches in order to quantify GRBV in infected plants and to identify potential biomarkers for viral infection. We present for the first time the physical detection on the protein level of the two GRBV genes V1 (coat protein) and V2 in grapevine tissue lysates. The GRBV coat protein load in leaf petioles was determined to be in the range of 100 to 900 million copies per milligram wet weight by using three heavy isotope labeled reference peptides as internal standards. The V1 copy number per unit wet tissue weight in leaves appeared to be about six times lower, and about 200-times lower in terms of protein concentration in the extractable protein mass than in petioles. We found a consistent upregulation of several enzymes involved in flavonoid biosynthesis in leaf and petiole extracts of GRBV-infected plants by label-free shotgun proteomics, indicating the activation of a defense mechanism against GRBV, a plant response already described for grapevine leafroll associated virus infection on the transcriptome level. Last but not least, we identified some other microorganisms belonging to the grapevine leaf microbiota, two bacterial species (Novosphingobium sp. Rr 2-17 and Methylobacterium) and one virus, Grapevine rupestris stem pitting associated virus.