Project description:We produced differentially sensitive-temperature phenotypes using genetically defined larval families of the bivalve Crassostrea gigas. Larval growth rates varied ~5-fold and reciprocal hybrids showed different genotype-dependent responses over a 15-25°C temperature range. Whole-genome expression analysis of ~24 million cDNAs from larvae identified 22,250 unique transcripts. Of these, ~15% showed a significant interaction between genotype and temperature and are associated with genotype-dependent differences in response to temperature. Examination of 2 genotypes of Pacific oyster larvae, grown at 3 temperatures
Project description:We produced differentially sensitive-temperature phenotypes using genetically defined larval families of the bivalve Crassostrea gigas. Larval growth rates varied ~5-fold and reciprocal hybrids showed different genotype-dependent responses over a 15-25°C temperature range. Whole-genome expression analysis of ~24 million cDNAs from larvae identified 22,250 unique transcripts. Of these, ~15% showed a significant interaction between genotype and temperature and are associated with genotype-dependent differences in response to temperature.
Project description:Mediterranean mussels are a worldwide spread bivalve species with extraordinary biological success. One of the reasons of this success could be the reproduction strategy of bivalves, characterized by the presence of trochophore larvae. Larval development in bivalves has been a topic of raising interest in the scientific community but it deserves much more attention. The principal objective of this work was to study the transcriptomic profile of the ontogeny of M. galloprovincialis analyzing the gene expression in different developmental stages, from oocytes to seed. For this purpose, after conducting a 454 sequencing of transcriptome of mussel hemocytes, adult tissues and larvae, a new DNA microarray comprising sequences of was designed and developed. The studied developmental stages: unfertilized oocytes, veliger (3 days post fertilization; dpf) and pediveliger (20dpf) larvae, settled juveniles (25dpf) and seed (30dpf), showed very different transcriptomic profiles and clustered in groups defining their characteristic gene expression along ontogeny.
Project description:Pacific geoduck (Panopea generosa) clams are found along the Northeast Pacific coast where they are significant components of coastal and estuarine ecosystems and the basis of a highly profitable aquaculture industry. The Pacific coastline, however, is also the sight of rapidly changing ocean habitat, including significant reductions in pH. To better understand the physiological impact of ocean acidification on geoduck clams, we characterized for the first time the proteomic profile of this bivalve during early larval development and compared it to that of larvae exposed to low pH.Geoduck larvae wer reared at pH 7.5 (ambient) or 7.1 in a commercial shellfish hatchery from day 6 to 19 post-fertilization , and sampled at six time points for an in-depth proteomics analysis using high-resolution data dependent analysis. We found that larvae reared at low pH were smaller than those reared at ambient pH, especially in the prodissoconch II phase of development, and displayed a delay in their competency for settlement. Proteomic profiles revealed that metabolic, cell cycle, and protein turnover pathways differed between the two pH, suggesting that differing phenotypic outcomes between pH 7.5 and 7.1 are likely due to environmental disruptions to the timing of molecular physiological events. In summary, ocean acidification likely caused an energetic stress on geoduck larvae, casuing a shift in physiological prioritization.
Project description:The Portuguese oyster Crassostrea angulata, a bivalve of significant economic and ecological importance, has faced a decline in both production and natural populations due to pathologies, climate change, and anthropogenic factors. To safeguard its genetic diversity and improve reproductive management, cryopreservation emerges as a valuable strategy. However, the cryopreservation methodologies lead to some damage in structures and functions of the cells and tissues that can affect post-thaw quality. Transcriptomics may help to understand the molecular consequences related to cryopreservation steps and therefore to identify different freezability biomarkers. This study investigates the molecular damage induced by cryopreservation in C. angulata D-larvae, focusing on two critical steps: exposure to cryoprotectant solution and the freezing/thawing process. Expression analysis revealed 3 differentially expressed genes between larvae exposed to cryoprotectant solution and fresh larvae and 511 differentially expressed genes in cryopreserved larvae against fresh larvae. The most significantly enriched gene ontology terms were “carbohydrate metabolic process”, “integral component of membrane” and “chitin binding” for biological processes, cellular components and molecular functions, respectively. Kyoto Encyclopedia of Genes and Genomes enrichment analysis identified the “neuroactive ligand receptor interaction”, “endocytosis” and “spliceosome” as the most enriched pathways. RNA sequencing results were validate by quantitative RT-PCR, once both techniques presented the same gene expression tendency and a group of 11 genes were considered important molecular biomarkers to be used in further studies for the evaluation of cryodamage. The current work provided valuable insights into the molecular repercussions of cryopreservation on D-larvae of Crassostrea angulata, revealing that the freezing process had a more pronounced impact on larval quality compared to any potential cryoprotectant-induced toxicity. Additionally, was identify 11 genes serving as biomarkers of freezability for D-larvae quality assessment. This research contributes to the development of more effective cryopreservation protocols and detection methods for cryodamage in this species.
Project description:The Manila clam (Ruditapes philippinarum) is a cultured bivalve species with high worldwide commercial importance. Nevertheless, diseases can cause high economical losses. For this reason, the study of immune genes in bivalve mollusks has increased in the last years. The present work describes the construction of the first R. philippinarum microarray containing immune-related hemocyte sequences and its application for the study of the gene transcription profiles of hemocytes from clams challenged with Vibrio alginolyticus through a time course.