Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China.
Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.
Front Immunol. 2022 Sep 29;13:974604. doi: 10.3389/fimmu.2022.974604. eCollection 2022.
Infectious diseases have caused dramatic production decline and economic loss for fish aquaculture. However, the poor understanding of fish disease resistance severely hampered disease prevention. Chinese tongue sole () is an important economic flatfish suffering from vibriosis. Here we used genomic, transcriptomic and experimental approaches to investigate the molecular genetic mechanisms underlying fish vibriosis resistance. A genome-wide comparison revealed that the genes under selective sweeps were enriched for glycosaminoglycan (GAG) chondroitin sulfate (CS)/dermatan sulfate (DS) metabolism. Transcriptomic analyses prioritized synergic gene expression patterns in this pathway, which may lead to an increased CS/DS content in the resistant family. Further experimental evidence showed that carbohydrate sulfotransferases 12 (Chst12), a key enzyme for CS/DS biosynthesis, has a direct antibacterial activity. To the best of our knowledge, this is the first report that the gene has a bactericidal effect. In addition, CS/DS is a major component of the extracellular matrix (ECM) and the selection signatures and fine-tuned gene expressions of ECM-receptor interaction genes indicated a modification in the ECM structure with an enhancement of the barrier function. Furthermore, functional studies conducted on Col6a2, encoding a collagen gene which constitutes the ECM, pointed to that it may act as a cellular receptor for pathogens, thus plays an important role for the invasion. Taken together, these findings provide new insights into the molecular protective mechanism underlying vibriosis resistance in fish, which offers crucial genomic resources for the resistant germplasm breeding and infectious disease control in fish culturing.
传染病导致鱼类养殖产量大幅下降和经济损失。然而，对鱼类疾病抵抗力的认识不足严重阻碍了疾病的预防。中国牙鲆（）是一种重要的经济比目鱼，易患弧菌病。在这里，我们使用基因组、转录组和实验方法研究了鱼类抗弧菌病的分子遗传机制。全基因组比较表明，选择清除的基因富集了糖胺聚糖（GAG）硫酸软骨素（CS）/硫酸皮肤素（DS）代谢。转录组分析优先考虑了该途径中的协同基因表达模式，这可能导致抗性家系中 CS/DS 含量增加。进一步的实验证据表明，碳水化合物磺基转移酶 12（Chst12），CS/DS 生物合成的关键酶，具有直接的抗菌活性。据我们所知，这是第一个报道基因具有杀菌作用的报告。此外，CS/DS 是细胞外基质（ECM）的主要成分，ECM-受体相互作用基因的选择特征和精细调节的基因表达表明 ECM 结构发生了修饰，屏障功能得到了增强。此外，对构成 ECM 的胶原基因 Col6a2 进行的功能研究表明，它可能作为病原体的细胞受体发挥作用，因此在入侵过程中起着重要作用。总之，这些发现为鱼类抗弧菌病的分子保护机制提供了新的见解，为鱼类抗性种质资源的培育和水产养殖中传染病的控制提供了重要的基因组资源。
