Key Laboratory for Sustainable Utilization of Marine Fisheries Resources, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China.
PLoS One. 2013 Dec 3;8(12):e82155. doi: 10.1371/journal.pone.0082155. eCollection 2013.
The swimming crab, Portunus trituberculatus, which is naturally distributed in the coastal waters of Asia-Pacific countries, is an important farmed species in China. Salinity is one of the most important abiotic factors that influence not only the distribution and abundance of crustaceans, it is also an important factor for artificial propagation of the crab. To better understand the interaction between salinity stress and osmoregulation, we performed a transcriptome analysis in the gills of Portunus trituberculatus challenged with salinity stress, using the Illumina Deep Sequencing technology.
We obtained 27,696,835, 28,268,353 and 33,901,271 qualified Illumina read pairs from low salinity challenged (LC), non-challenged (NC), and high salinity challenged (HC) Portunus trituberculatus cDNA libraries, respectively. The overall de novo assembly of cDNA sequence data generated 94,511 unigenes, with an average length of 644 bp. Comparative genomic analysis revealed that 1,705 genes differentially expressed in salinity stress compared to the controls, including 615 and 1,516 unigenes in NC vs LC and NC vs HC respectively. GO functional enrichment analysis results showed some differentially expressed genes were involved in crucial processes related to osmoregulation, such as ion transport processes, amino acid metabolism and synthesis processes, proteolysis process and chitin metabolic process.
This work represents the first report of the utilization of the next generation sequencing techniques for transcriptome analysis in Portunus trituberculatus and provides valuable information on salinity adaptation mechanism. Results reveal a substantial number of genes modified by salinity stress and a few important salinity acclimation pathways, which will serve as an invaluable resource for revealing the molecular basis of osmoregulation in Portunus trituberculatus. In addition, the most comprehensive sequences of transcripts reported in this study provide a rich source for identification of novel genes in the crab.
三疣梭子蟹（Portunus trituberculatus）自然分布于亚太国家的沿海水域，是中国重要的养殖品种。盐度是影响甲壳类动物分布和丰度的最重要非生物因素之一，也是蟹类人工繁殖的重要因素。为了更好地了解盐度胁迫与渗透调节之间的相互作用，我们使用 Illumina 高通量测序技术对三疣梭子蟹鳃组织进行了转录组分析。
我们从低盐胁迫（LC）、未胁迫（NC）和高盐胁迫（HC）三疣梭子蟹 cDNA 文库中分别获得了 27,696,835、28,268,353 和 33,901,271 条合格的 Illumina 读对。cDNA 序列数据的从头组装共生成了 94,511 条 unigenes，平均长度为 644bp。比较基因组分析显示，与对照组相比，盐胁迫下有 1,705 个基因差异表达，其中 NC 与 LC 相比有 615 个 unigenes，NC 与 HC 相比有 1,516 个 unigenes。GO 功能富集分析结果表明，一些差异表达基因参与了与渗透调节相关的关键过程，如离子转运过程、氨基酸代谢和合成过程、蛋白水解过程和几丁质代谢过程。
本研究首次利用下一代测序技术对三疣梭子蟹进行了转录组分析，为盐度适应机制提供了有价值的信息。结果显示，大量基因受到盐度胁迫的调节，一些重要的盐度适应途径也被揭示，这将为揭示三疣梭子蟹渗透调节的分子基础提供宝贵资源。此外，本研究中报道的最全面的转录本序列为鉴定蟹类中的新基因提供了丰富的资源。
