Development of single nucleotide polymorphisms in key genes of taurine and betaine metabolism in Crassostrea hongkongensis and their association with content-related traits.

Background: Taurine and betaine are important nutrients in the Hong Kong oyster (Crassostrea hongkongensis) and have many important biological properties. To investigate the characteristics of taurine and betaine and identify single nucleotide polymorphisms (SNPs) associated with traits in C. hongkongensis, we cloned the full-length cDNA of key genes involved in taurine and betaine metabolism (unpublished data), determined taurine and betaine content and gene expression in different tissues and months of the oyster specimen collection, and developed SNPs in the gene coding region.

Development of single nucleotide polymorphisms in key genes of taurine and betaine metabolism in Crassostrea hongkongensis and their association with content-related traits.

Background: Taurine and betaine are important nutrients in and have many important biological properties. To investigate the characteristics of taurine and betaine contents and identify SNPs associated with traits in the , we cloned the full-length cDNA of key genes in taurine and betaine (unpublished data) metabolism, determined taurine and betaine content and gene expression in different tissues and months of specimen collection, and developed SNPs in the gene coding region.

Results: We cloned the full-length cDNA of cysteine dioxygenase () and cysteine sulfite decarboxylase (), which are key genes involved in taurine metabolism in , and found that betaine and taurine contents and the expression of key genes were regulated by seawater salinity.

Adaptive divergence and underlying mechanisms in response to salinity gradients between two oysters revealed by phenotypic and transcriptomic analyses.

Comparing the responses of closely related species to environmental changes is an efficient method to explore adaptive divergence, for a better understanding of the adaptive evolution of marine species under rapidly changing climates. Oysters are keystone species thrive in intertidal and estuarine areas where frequent environmental disturbance occurs including fluctuant salinity. The evolutionary divergence of two sister species of sympatric estuarine oysters, and , in response to euryhaline habitats on phenotypes and gene expression, and the relative contribution of species effect, environment effect, and their interaction to the divergence were explored.

Population resequencing reveals candidate genes associated with salinity adaptation of the Pacific oyster Crassostrea gigas.

The Pacific oyster Crassostrea gigas is an important cultivated shellfish. As a euryhaline species, it has evolved adaptive mechanisms responding to the complex and changeable intertidal environment that it inhabits. To investigate the genetic basis of this salinity adaptation mechanism, we conducted a genome-wide association study using phenotypically differentiated populations (hyposalinity and hypersalinity adaptation populations, and control population), and confirmed our results using an independent population, high-resolution melting, and mRNA expression analysis.

Candidate Gene Polymorphisms and their Association with Glycogen Content in the Pacific Oyster Crassostrea gigas.

Background: The Pacific oyster Crassostrea gigas is an important cultivated shellfish that is rich in nutrients. It contains high levels of glycogen, which is of high nutritional value. To investigate the genetic basis of this high glycogen content and its variation, we conducted a candidate gene association analysis using a wild population, and confirmed our results using an independent population, via targeted gene resequencing and mRNA expression analysis.

Genome and transcriptome analyses provide insight into the euryhaline adaptation mechanism of Crassostrea gigas.

Background: The Pacific oyster, Crassostrea gigas, has developed special mechanisms to regulate its osmotic balance to adapt to fluctuations of salinities in coastal zones. To understand the oyster's euryhaline adaptation, we analyzed salt stress effectors metabolism pathways under different salinities (salt 5, 10, 15, 20, 25, 30 and 40 for 7 days) using transcriptome data, physiology experiment and quantitative real-time PCR.

Results: Transcriptome data uncovered 189, 480, 207 and 80 marker genes for monitoring physiology status of oysters and the environment conditions.