Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China.
Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China.
Fish Shellfish Immunol. 2019 Jan;84:920-926. doi: 10.1016/j.fsi.2018.10.079. Epub 2018 Oct 29.
The globular C1q domain containing (C1qDC) proteins are a family of versatile pattern recognition receptors (PRRs) to bind various ligands by their globular C1q (gC1q) domain. In the present study, a novel globular C1qDC (CgC1qDC-7) was characterized from Pacific oyster Crassostrea gigas. The open reading frame of CgC1qDC-7 was of 555 bp, encoding a polypeptide of 185 amino acids. Phylogenetic analysis indicated that CgC1qDC-7 shared high homology with C1qDCs from Crassostrea virginica, Mytilus galloprovincialis, and Mizuhopecten yessoensis. The mRNA transcripts of CgC1qDC-7 were widely expressed in all the tested tissues including mantle, gonad, gills, adductor muscle, hemocytes, hepatopancreas and labial palps, with the highest expression level in hemocytes and gills. The recombinant protein of CgC1qDC-7 (rCgC1qDC-7) exhibited binding activity towards Gram-negative bacteria (Vibrio splendidus, V. anguillarum, Escherichia coli, V. alginolyticus, and Aeromonas hydrophila), Gram-positive bacteria (Micrococcus luteus and Staphylococcus aureus) and fungi (Pichia pastoris and Yarrowia lipolytica), and displayed strongest binding affinity towards Gram-negative bacteria V. splendidus and V. anguillarum. It also exhibited affinity to vital pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS), peptidoglycan (PGN), mannan (MAN) and Poly (I:C) with high affinity towards LPS and PGN, and low affinity to MAN and Poly (I:C). These results collectively indicated that CgC1qDC-7 was a novel PRR in C. gigas with high binding affinity towards LPS and PGN as well as Gram-negative bacteria.
球形 C1q 域包含蛋白（C1qDC）是一类多功能模式识别受体（PRR），通过其球形 C1q（gC1q）结构域结合各种配体。在本研究中，从太平洋牡蛎 Crassostrea gigas 中鉴定了一种新型球形 C1qDC（CgC1qDC-7）。CgC1qDC-7 的开放阅读框为 555bp，编码 185 个氨基酸的多肽。系统进化分析表明，CgC1qDC-7 与 Crassostrea virginica、Mytilus galloprovincialis 和 Mizuhopecten yessoensis 的 C1qDCs 具有高度同源性。CgC1qDC-7 的 mRNA 转录本广泛表达于所有检测组织，包括套膜、性腺、鳃、闭壳肌、血细胞、肝胰腺和唇瓣，在血细胞和鳃中的表达水平最高。CgC1qDC-7 的重组蛋白（rCgC1qDC-7）表现出对革兰氏阴性菌（灿烂弧菌、鳗弧菌、大肠杆菌、解藻酸弧菌和嗜水气单胞菌）、革兰氏阳性菌（藤黄微球菌和金黄色葡萄球菌）和真菌（巴氏毕赤酵母和解脂耶氏酵母）的结合活性，并且对革兰氏阴性菌灿烂弧菌和鳗弧菌表现出最强的结合亲和力。它还对重要的病原体相关分子模式（PAMPs）表现出亲和力，如脂多糖（LPS）、肽聚糖（PGN）、甘露聚糖（MAN）和聚肌苷酸：聚胞苷酸（Poly（I:C）），对 LPS 和 PGN 具有高亲和力，对 MAN 和 Poly（I:C）具有低亲和力。这些结果共同表明，CgC1qDC-7 是太平洋牡蛎 C. gigas 中的一种新型 PRR，对 LPS 和 PGN 以及革兰氏阴性菌具有高结合亲和力。
