Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China.
Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Marine Science and Engineering College, Qingdao Agricultural University, Qingdao 266109, China; Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China.
Fish Shellfish Immunol. 2018 Jan;72:658-669. doi: 10.1016/j.fsi.2017.11.017. Epub 2017 Nov 13.
Complement component C8, which mediates membrane attack complex formation and bacterial lysis, plays important roles in the complement system. The cDNA sequences of the C8α, C8β and C8γ genes were cloned from half-smooth tongue sole (Cynoglossus semilaevis). Full-length cDNA of CsC8α (C8α of C. semilaevis), CsC8β and CsC8γ was 1990, 2219 and 886 bp, respectively, which contained open reading frames of 1797, 1749 and 666 bp, encoding 598, 582 and 221 amino acids, respectively. The deduced proteins of CsC8α, CsC8β and CsC8γ showed the closest amino acid similarity to C8α (73%) of Siniperca chuatsi, C8β (76%) of Oryzias latipes and C8γ (72%) of Takifugu rubripes, respectively. The highest expression level of CsC8α, CsC8β and CsC8γ among the 13 normal tissues was observed in liver tissue, followed by much lower levels in other tissues. After infection with Vibrio anguillarum, CsC8α, CsC8β and CsC8γ were significantly up-regulated in all of the detected tissues, including the intestine, liver, gill, head kidney, blood and spleen. Then, a recombinant expression plasmid was constructed, and the recombinant CsC8α protein was expressed in GS115 pichia pastoris yeast. Furthermore, to investigate the biological functions of recombinant CsC8α, an antibacterial assay was performed, and the results showed that recombinant CsC8α obviously inhibited growth of V. anguillarum, Edwardsiella tarda and Vibrio parahaemolyticus. Taken together, these results suggest that CsC8α, CsC8β and CsC8γ may play important roles in the immune defense of C. semilaevis.
补体成分 C8 介导膜攻击复合物的形成和细菌裂解，在补体系统中发挥重要作用。从半滑舌鳎（Cynoglossus semilaevis）中克隆了 C8α、C8β 和 C8γ 基因的 cDNA 序列。全长 cDNA 的 CsC8α（C. semilaevis 的 C8α）、CsC8β 和 CsC8γ 分别为 1990、2219 和 886 bp，分别包含 1797、1749 和 666 bp 的开放阅读框，分别编码 598、582 和 221 个氨基酸。CsC8α、CsC8β 和 CsC8γ 的推导蛋白与 Siniperca chuatsi 的 C8α（73%）、Oryzias latipes 的 C8β（76%）和 Takifugu rubripes 的 C8γ（72%）的氨基酸最相似。在 13 种正常组织中，CsC8α、CsC8β 和 CsC8γ 的表达水平最高的组织是肝脏，其次是其他组织。感染鳗弧菌后，CsC8α、CsC8β 和 CsC8γ 在所有检测组织中均显著上调，包括肠、肝、鳃、头肾、血液和脾脏。然后，构建了一个重组表达质粒，并在 GS115 毕赤酵母中表达了重组 CsC8α 蛋白。此外，为了研究重组 CsC8α 的生物学功能，进行了抗菌测定，结果表明重组 CsC8α 明显抑制了鳗弧菌、迟缓爱德华氏菌和副溶血弧菌的生长。总之，这些结果表明 CsC8α、CsC8β 和 CsC8γ 可能在半滑舌鳎的免疫防御中发挥重要作用。
