New Insights into the Differences Between Triploid and Diploid Fujian Oyster By Integrated Gene Expression Profiling and Proteomic Analyses

The Fujian oyster, Crassostrea angulata, is the primary oyster species in southern China, which accounts for about 50% of the total oyster production in China. Many studies revealed that triploid oyster showed the significant advantages on the growth compared with the common diploid oyster. In this study, we compared the difference of physiological, gene expression profiling and proteomics on diploid and triploid C. angulata.

After 10 months grow-out, the mean shell height, body weight, adductor muscle weight and glycogen content in adductor muscle of triploids oyster were 10.0%, 29.6%, 40.0% and 189.8% more than diploids, respectively (P<0.05). Based on digital gene expression analysis, 814 DEGs were significantly up-regulated and 1231 DEGs were down-regulated in 2N in comparison with 3N. In addition, there were 24 DEGs specially expressed in 2N while 28 DEGs specially in 3N. Through the KEGG and GO results, functions and pathways related to growth-metabolism and growth-development were mostly found in 3N and 2N samples, respectively. iTRAQ proteomics analyses revealed that 77 differentially expressed proteins were significantly up-regulated and 45 were down-regulated in 2N in comparison with 3N. In addition, there were 5 differentially expressed proteins specially expressed in 2N while 7 specially in 3N.

This is the first report on genome-wide transcriptional and proteomics analysis of diploid and triploid Fujian oyster. This study provides a foundation for further analysis of the gene expression patterns and signaling pathways which regulate the molecular mechanisms of diploid and triploid oyster.