South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou 510300, China.
South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou 510300, China.
Fish Shellfish Immunol. 2018 Jan;72:117-123. doi: 10.1016/j.fsi.2017.10.051. Epub 2017 Oct 31.
Chitinases are crucial enzymes for crustaceans. Previous researches had already revealed that chitinases play important roles in digestion, molting and defense against viruses. In the present study, a chitinase cDNA was identified from black tiger shrimp (Penaeus monodon) and designated as PmChi-5. The full-length PmChi-5 cDNA was 2860 bp in size, containing an open reading frame (ORF) of 1731 bp that encoded a protein of 576 amino acids with a deduced molecular weight of 64.8 kDa. Expression of the PmChi-5 mRNA was ubiquitously detected in all selected tissues, with the highest level in the gill and hepatopancreas. PmChi-5 was expressed throughout the whole larvae stages, and the highest level at Mysis3 stage, which indicated that PmChi-5 may be involved in larval metamorphosis. After challenged with Streptococcus agalactiae and Vibrio harveyi, the transcripts of PmChi-5 were found to be up-regulated significantly both in hepatopancreas and gill. Besides, the ammonia nitrogen stress treatment was also carried out, PmChi-5 transcripts were significantly changed in hepatopancreas and gill. The results showed that PmChi-5 may be involved in molting, larval metamorphosis, the immune defenses to pathogens infection and ammonia-N stress.
几丁质酶是甲壳类动物的重要酶。先前的研究已经表明，几丁质酶在消化、蜕皮和抵抗病毒方面发挥着重要作用。在本研究中，从黑虎虾（Penaeus monodon）中鉴定出一种几丁质酶 cDNA，并将其命名为 PmChi-5。PmChi-5 的全长 cDNA 大小为 2860bp，包含一个 1731bp 的开放阅读框（ORF），编码 576 个氨基酸的蛋白质，推断分子量为 64.8kDa。PmChi-5 mRNA 在所有选定的组织中均广泛表达，在鳃和肝胰腺中的表达水平最高。PmChi-5 在整个幼虫阶段都有表达，在 Mysis3 阶段表达水平最高，这表明 PmChi-5 可能参与幼虫变态。在受到副溶血弧菌和哈维弧菌的刺激后，PmChi-5 的转录本在肝胰腺和鳃中均显著上调。此外，还进行了氨氮应激处理，PmChi-5 的转录本在肝胰腺和鳃中均发生显著变化。结果表明，PmChi-5 可能参与蜕皮、幼虫变态、对病原体感染和氨氮胁迫的免疫防御。
