Li Changping, Wang Fan, Aweya Jude Juventus, Yao Defu, Zheng Zhou, Huang He, Li Shengkang, Zhang Yueling
Department of Biology, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
Department of Biology, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
Dev Comp Immunol. 2018 Feb;79:95-104. doi: 10.1016/j.dci.2017.10.015. Epub 2017 Oct 24.
Hemocyanin is a copper containing respiratory glycoprotein in arthropods and mollusks, which also have multiple functions in vivo. Recent studies have shown that hemocyanin could generate several peptides, which play important roles in shrimp innate immunity. However, how these hemocyanin-derived peptides are generated is still largely unknown. In this study, we report for the first time that the generation of hemocyanin-derived peptides was closely correlated with trypsin expression in shrimp hepatopancreas following infection with different bacteria. RNA interference (RNAi) mediated knockdown of trypsin or treatment with the serine protease inhibitor, aprotinin, resulted in significant decrease in the levels of hemocyanin-derived peptides. Moreover, recombinant trypsin (rTrypsin) was able to hydrolyse hemocynin in vitro with the hydrolysate having a high bacterial agglutination activity while the denatured hemocynin untreated with rTrypsin lost its agglutination activity. Taken together, our current results showed that the generation of hemocyanin-derived peptides correlates with an increase trypsin expression.
血蓝蛋白是节肢动物和软体动物中一种含铜的呼吸糖蛋白，在体内也具有多种功能。最近的研究表明，血蓝蛋白可以产生几种肽，这些肽在虾的先天免疫中发挥重要作用。然而，这些血蓝蛋白衍生肽是如何产生的在很大程度上仍然未知。在本研究中，我们首次报道，在感染不同细菌后，虾肝胰腺中血蓝蛋白衍生肽的产生与胰蛋白酶表达密切相关。RNA干扰（RNAi）介导的胰蛋白酶敲低或用丝氨酸蛋白酶抑制剂抑肽酶处理，导致血蓝蛋白衍生肽水平显著降低。此外，重组胰蛋白酶（rTrypsin）能够在体外水解血蓝蛋白，水解产物具有高细菌凝集活性，而未经rTrypsin处理的变性血蓝蛋白失去其凝集活性。综上所述，我们目前的结果表明，血蓝蛋白衍生肽的产生与胰蛋白酶表达的增加相关。
