Project description:As marine invertebrates, oysters lack adaptive immunity and employ innate immunity as the front line and lmost the solo defense mechanism to protect them against invaders. Accumulating research achievements demonstrated that exosomes could act as innate immune effectors that contribute to host defense mechanism. To better understand the immune functions of exosomes in Crassostrea gigas against bacterial stimulation, iTRAQ was applied to explore the global protein changes of exosomes in oyster after Staphylococcus aureus and Vibrio splendidus stimulation.
Project description:Deep sequencing of samples from different development stages, different adult organs and different stress treatments of Pacific oyster Crassostrea gigas Samples of 38 developmental stages from egg to juvenile were analyzed using single-end 49 bp RNA-seq. Two libraries mixed by RNAs from different developmental stages were analyzed using paired-end 90 bp RNA-seq. A total of 11 samples mainly from 8 organs (mantle, gill,adductor muscle, digestive gland, hemocyte, labial palp, female gonad and male gonad) were analyzed using paired-end 90 bp RNA-seq. At the same time, single-end 49 bp RNA-seq was conducted on 61 samples collected from adult oysters subjected to 9 types of environmental stressors (exposure to air, salinity, temperature, and exposure to metals).
Project description:Deep sequencing of mRNA from Pacific oyster Crassostrea gigas Competent larvae of Crassostrea gigas were treated with epinephrine solution, and then sampled at different time intervals. For shell damage experiment, shell were broken and then tissues were sampled at different time intervals.
Project description:Marine intertidal organisms commonly face hypoxic stress during low tide emersion; moreover, eutrophic conditions and sediment nearness could lead to hypoxic phenomena; it is indeed important to understand the molecular processes involved in the response to hypoxia. In this study the molecular response of the Pacific oyster Crassostrea gigas to prolonged hypoxia (2 mg O2 L-1 for 20 d) was investigated under experimental conditions. A transcriptomic approach was employed using a cDNA microarray of 9058 C. gigas clones to highlight the genetic expression patterns of the Pacific oyster under hypoxic conditions. Lines of oysters resistant (R) and susceptible (S) to summer mortality were used in this study. This is the first study employing microarrays to characterize the genetic markers and metabolic pathways responding to hypoxic stress in C. gigas.
Project description:Research using the oyster Crassostrea gigas as a model has experienced a rapid growth in recent years thanks to the development of high throughput molecular technologies. As many as 56,268 EST sequences have so far been sequenced, representing a genome-wide resource that can be used for microarray investigations. We have developed an oyster microarray containing cDNAs representing 31,918 unique transcribed sequences. The genes spotted on the array have been selected from the publicly accessible GigasDatabase established from cDNA libraries derived from a wide variety of tissues and different developmental stages. n this paper, we report the transcriptome of male and female gonads, mantle, gills, posterior adductor muscle, visceral ganglion, hemocytes, labial palps and digestive gland. Following validation of the microarray, statistical analyses were used to identify genes differentially expressed among tissues and define clusters of tissue-specific genes. These genes reflect well major tissue-specific functions at the molecular level. Analysis of hierarchical clustering data also predicted the involvement of un-annotated genes in selected functional pathways. In a second instance, microarray data were used to accurately select housekeeping genes common to all tissues. Their expression profiles was compared to common oyster standard genes used for quantitative RT-PCR calibration (actin, g3apdh and ef1α). The novel candidate housekeeping gene, adp-ribosylation factor 1 (arf1) and g3apdh gene seem to be more robust for normalizing gene expression data of tissues. This study provides a new source for annotating the oyster genome. It also identified new candidate housekeeping genes, a prerequisite for accurate quantitative RT-PCR expression profiling. Gene expression was measured in 9 tissues: Female gonad, male gonad, mantle, gills, posterior adductor muscle, visceral ganglion, hemocytes, labial palps, digestive gland.Three to four biological replicates were analysed per tissue. These were from distinct animals for female gonad, male gonad, mantle, gills, posterior adductor muscle, labial palps and digestive glands, or obtained from a pool of 6 individuals for hemocytes and visceral ganglion.
Project description:The mantle is a thin tissue from which proteins are secreted dictating the mollusk shell construction. As a conserved organ involved in shell formation throughout mollusks, the mantle is an excellent foundation from which to study biomineralization. A P. maxima mantle tissue specific cDNA microarray, termed PmaxArray 1.0, has been developed comprising 5000 cDNA transcripts derived from the mantle tissue of P. maxima. This tool has been used to investigate the spatial functional dynamics of the mantle tissue identifying over 2000 PmaxArray 1.0 spots as differentially expressed spatially within this organ. Gene expression profiles observed for these transcripts indicated 5 major spatial functions for the mantle, 3 of which have been putatively attributed to shell formation roles associated with nacre microstructure, calcite prismatic microstructure and periostracum. These transcripts are further examined with in situ expression localization and comparative sequence analyses in reference to potential shell formation roles. This spatial investigation has expedited the elucidation of functions within the dynamic mantle organ, paying particular attention to of shell biomineralization. Keywords: Spatial expression profiling by array
Project description:The experiment is for demonstrating the miRNA profiles in plasma exosomes derived from mild cognitive impairment and Alzheimer's disease patients and healthy donors.