Godahewa G I, Wickramaarachchi W D Niroshana, Whang Ilson, Bathige S D N K, Lim Bong-Soo, Choi Cheol Young, De Zoysa Mahanama, Noh Jae Koo, Lee Jehee
Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
Vet Immunol Immunopathol. 2014 Dec 15;162(3-4):180-91. doi: 10.1016/j.vetimm.2014.10.005. Epub 2014 Oct 22.
Carboxypeptidases (CPs) are proteases that hydrolyze C-terminal peptide bonds. They are involved in regulating the complement system of the immune system. Here, we report the molecular characterization and immune response of two carboxypeptidases, named carboxypeptidase A (Rb-CPA) and carboxypeptidase N1 (Rb-CPN1), from rock bream. The genomic sequence of Rb-CPA contains 12 exons interrupted by 11 introns, while the genomic sequence of Rb-CPN1 has 9 exons and 8 introns. The cDNA sequence of Rb-CPA encodes a 421-amino-acid (AA) polypeptide (48kDa), and the cDNA of Rb-CPN1 encodes a 448-AA polypeptide (51kDa). The amino acid sequences of Rb-CPA and Rb-CPN1 were found to harbor two characteristic Zn-binding signature domains and a peptidase-M14 Zn carboxypeptidase site. Pairwise analysis revealed that Rb-CPA and Rb-CPN1 had the highest identity with the corresponding proteins from Anoplopoma fimbria (87.6%) and Dicentrarchus labrax (96.9%), respectively. qPCR results indicated that Rb-CPA and Rb-CPN1 were constitutively expressed mainly in the kidney, heart, liver, and head kidney. Both genes were transcriptionally regulated in the liver upon challenge with pathogenic bacteria (Streptococcus iniae, Edwardsiella tarda), rock bream iridovirus (RBIV), and the immune modulators polyinosinic:polycytidylic acid and lipopolysaccharide. Taken together, our findings suggest that Rb-CPA and Rb-CPN1 have immune-related functions in rock bream.
羧肽酶（CPs）是一类能水解C端肽键的蛋白酶。它们参与免疫系统补体系统的调节。在此，我们报告了来自条石鲷的两种羧肽酶的分子特征和免疫反应，这两种羧肽酶分别命名为羧肽酶A（Rb-CPA）和羧肽酶N1（Rb-CPN1）。Rb-CPA的基因组序列包含12个外显子，被11个内含子打断，而Rb-CPN1的基因组序列有9个外显子和8个内含子。Rb-CPA的cDNA序列编码一个421个氨基酸（AA）的多肽（48kDa），Rb-CPN1的cDNA编码一个448个AA的多肽（51kDa）。发现Rb-CPA和Rb-CPN1的氨基酸序列含有两个特征性的锌结合签名结构域和一个肽酶-M14锌羧肽酶位点。成对分析表明，Rb-CPA和Rb-CPN1分别与黄线狭鳕和欧洲鲈鱼的相应蛋白质具有最高的同源性（分别为87.6%和96.9%）。qPCR结果表明，Rb-CPA和Rb-CPN1主要在肾脏、心脏、肝脏和头肾中组成性表达。在用病原菌（海豚链球菌、迟缓爱德华氏菌）、条石鲷虹彩病毒（RBIV）以及免疫调节剂聚肌苷酸:聚胞苷酸和脂多糖攻击后，这两个基因在肝脏中均受到转录调控。综上所述，我们的研究结果表明Rb-CPA和Rb-CPN1在条石鲷中具有免疫相关功能。
