Department of Marine Biology & Aquaculture, Institute of Marine Industry, College of Marine Science, Gyeongsang National University, Tongyeong, Republic of Korea.
Fish Shellfish Immunol. 2013 Jul;35(1):188-94. doi: 10.1016/j.fsi.2013.04.016. Epub 2013 Apr 28.
Cathepsins are lysosomal cysteine proteases belonging to the papain family, whose members play important roles in normal metabolism for the maintenance of cellular homeostasis. Rock bream (Oplegnathus fasciatus) cathepsin H (RbCTSH) cDNAs were identified by expressed sequence tag analysis of a lipopolysaccharide-stimulated rock bream liver cDNA library. The full-length RbCTSH cDNA (1326 bp) contained an open reading frame of 978 bp encoding 325 amino acids. The presence of an ERFNIN-like motif was predicted in the propeptide region of RbCTSH. Furthermore, multiple alignments showed that the EPQNCSAT region was well conserved among other cathepsin H sequences. Phylogenetic analysis revealed that RbCTSH is most closely related to Nile tilapia cathepsin H. RbCTSH was expressed significantly in the intestine, spleen, head kidney and stomach. RbCTSH mRNA expression was also examined in several tissues under conditions of bacterial and viral challenge. All examined tissues of fish infected with Edwardsiella tarda, Streptococcus iniae and red sea bream iridovirus (RSIV) showed significant increases in RbCTSH expression compared to the control. In the kidney and spleen, RbCTSH mRNA expression was upregulated markedly following infection with bacterial pathogens. These findings indicate that RbCTSH plays an important role in the innate immune response of rock bream. Furthermore, these results provide important information for the identification of other cathepsin H genes in various fish species.
组织蛋白酶是溶酶体半胱氨酸蛋白酶家族的成员，其成员在维持细胞内稳态的正常代谢中发挥重要作用。通过对脂多糖刺激的石斑鱼肝 cDNA 文库进行表达序列标签分析，鉴定了石斑鱼组织蛋白酶 H（RbCTSH）cDNA。RbCTSH 的全长 cDNA（1326bp）包含一个开放阅读框，长 978bp，编码 325 个氨基酸。在 RbCTSH 的前肽区预测存在一个 ERFNIN 样基序。此外，多重比对表明，EPQNCSAT 区域在其他组织蛋白酶 H 序列中高度保守。系统发育分析表明，RbCTSH 与尼罗罗非鱼组织蛋白酶 H 最为密切相关。RbCTSH 在肠道、脾脏、头肾和胃中表达显著。还检查了几种组织在细菌和病毒挑战条件下的 RbCTSH 表达。与对照组相比，感染迟钝爱德华氏菌、无乳链球菌和红鳍东方鲀虹彩病毒（RSIV）的所有检查组织的 RbCTSH 表达均显著增加。在肾脏和脾脏中，感染细菌病原体后 RbCTSH mRNA 表达明显上调。这些发现表明 RbCTSH 在石斑鱼的先天免疫反应中发挥重要作用。此外，这些结果为在各种鱼类中鉴定其他组织蛋白酶 H 基因提供了重要信息。
