Project description:Toxicogenomic analyses of Ruditapes philippinarum by DNA microarray: new tools for anthropogenic impact assessment on the Venice Lagoon.
Project description:A manila clam oligo microarray platform (GPL10900) was used to profile gene expression in digestive gland of R. philippinarum sampled in four seasons in 4 different areas of Venice Lagoon. For each tissue, total RNA was extracted from four (4) independent biological replicates of digestive gland, each consisting of tissue pools of five (5) animals.
Project description:We examined gene expression profiling of native mussels that were sampled in early summer 2003 from sites of the Venice lagoon area known to be differently affected by chemical pollution: Sites 1 and 2 close to the industrial district of Marghera and Site 3 close to the Lido lagoon outlet. Site 4, a current mussel farm located offshore, has been chosen as source of reference targets for microarray hybridizations. We have limited the preliminary assessment to the digestive gland. Digestive gland total RNA of each Site was hybridized in competition with the offshore mussels (Site 4 - Reference) and the relative abundance of each gene was measured by directly comparing fluorescent signals for each probe. We carried out two separate hybridizations for each site of the Venice lagoon area.. Keywords = digestive gland Keywords = Venice lagoon Keywords = chemical pollution Keywords = native mussels Keywords = transcriptional profiling Keywords: ordered
Project description:A manila clam oligo microarray platform (GPL10900) was used to profile gene expression in digestive gland of R. philippinarum sampled in four seasons in 4 different areas of Venice Lagoon. For each tissue, total RNA was extracted from four (4) independent biological replicates of digestive gland, each consisting of tissue pools of five (5) animals. In this study, we analyzed 64 samples (pools of 5 digestive gland). Gene expression profiling was performed using the Agilent-027304 Ruditapes philippinarum Oligo Microarray platform (GPL10900) based on single-colour detection (Cyanine-3 only). Microarrays were scanned with Agilent scanner G2565BA (barcode on the left, DNA on the back surface, scanned through the glass) at a resolution of 5 microns; all slides were scanned twice at two different sensitivity settings (XDRHi 100% and XDRLo 10%); the scanner software created a unique ID for each pair of XDR scans and saved it to both scan image files. Feature Extraction (FE) 9.5 used XDR ID to link the pairs of scans together automatically when extracting data. The signal left after all the FE processing steps have been completed is ProcessedSignal that contains the Multiplicatively Detrended, Background-Subtracted Signal.
Project description:A Ruditapes philippinarum microarray platform was developed to assess variations on transcritpomic response to copper exposures in Manila clam colelctted in Venice lagoon areas subjected to different anthropogenic impact
Project description:DNA microarray analyses of Ruditapes philippinarum sampled in Venice lagoon areas subjected to different anthropogenic impact. A comparative analysis of gene expression was conducted between Manila clam from lowly-polluted Chioggia and Colmata area and polluted Marghera site.
Project description:To access the nutritional quality of the Ruditapes philippinarum, a comprehensive quality evaluation procedure is always important to be established. In this study, fifteen nutritional quality evaluation indicators of R. philippinarum from 7 months were analyzed, and the most important indicators were determined using a combination of multiple chemometric methods such as correlation analysis (CA), principal component analysis (PCA), and system cluster analysis (SCA). Significant differences in nutritional quality were observed across the 7 months, as per the ANOVA results (P < 0.05). The coefficient of variation values for the fifteen evaluation indicators for R. philippinarum across 7 months was 1.67-43.47%. The CA results revealed that some indicators were correlated to each other within a certain range. Four principal components with eigen-values > 1 were obtained with PCA, and a cumulative contribution of 92.11% was achieved. In addition, four essential quality indicators were extracted using SCA. Using these four indicators, a simple and efficient procedure can be applied for quality control in aquaculture.
Project description:The Manila clam Ruditapes philippinarum is the world's second most important bivalve mollusk commercially farmed, whose indigenous populations are mainly distributed in the coastal areas of East Asia. However, with the development of commercialization, mixture of populations and loss of local germplasm have become prominent problems. Here, genetic differentiation of seven Manila clam populations from East Asia was investigated through analyzing the polymorphism of the mitochondrial cytochrome C oxidase subunit I (COI) gene as well as 20 simple sequence repeat (SSR) molecular loci. In total, 40 haplotypes were identified, among which 31 were unique. Moreover, two main haplotypes were detected with several radiating derived haplotypes. Populations in Japan-North Korea shared haplotype Hap_31, and populations in China shared haplotype Hap_7, suggesting that the natural geographical isolation of the Yangtze River and the Yalu River might have divided the East Asian indigenous populations into three groups, which were located in South China, North China, and Japan-North Korea, respectively. The Aquaculture breeding activities from South to North in China might have promoted gene exchange among Manila clam populations. Population in Laizhou had the highest genetic diversity and therefore could be an excellent germplasm source.
Project description:The manila clam, Ruditapes philippinarum, is an important bivalve species in worldwide aquaculture including Korea. The aquaculture production of R. philippinarum is under threat from diverse environmental factors including viruses, microorganisms, parasites, and water conditions with subsequently declining production. In spite of its importance as a marine resource, the reference genome of R. philippinarum for comprehensive genetic studies is largely unexplored. Here, we report the de novo whole-genome and transcriptome assembly of R. philippinarum across three different tissues (foot, gill, and adductor muscle), and provide the basic data for advanced studies in selective breeding and disease control in order to obtain successful aquaculture systems. An approximately 2.56 Gb high quality whole-genome was assembled with various library construction methods. A total of 108,034 protein coding gene models were predicted and repetitive elements including simple sequence repeats and noncoding RNAs were identified to further understanding of the genetic background of R. philippinarum for genomics-assisted breeding. Comparative analysis with the bivalve marine invertebrates uncover that the gene family related to complement C1q was enriched. Furthermore, we performed transcriptome analysis with three different tissues in order to support genome annotation and then identified 41,275 transcripts which were annotated. The R. philippinarum genome resource will markedly advance a wide range of potential genetic studies, a reference genome for comparative analysis of bivalve species and unraveling mechanisms of biological processes in molluscs. We believe that the R. philippinarum genome will serve as an initial platform for breeding better-quality clams using a genomic approach.