Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China.
Fish Shellfish Immunol. 2012 Oct;33(4):916-25. doi: 10.1016/j.fsi.2012.08.001. Epub 2012 Aug 8.
Translationally controlled tumor protein (TCTP) is an important molecule involved in multiple biological processes, such as cell growth, cell cycle progression, malignant transformation, and enhancement of the anti-apoptotic activity. In this study, the TCTP from orange-spotted grouper Epinephelus coioides (Ec-TCTP) was cloned and characterized. The full-length cDNA of Ec-TCTP was comprised of 1057 bp with a 510 bp open reading frame that encodes a putative protein of 170 amino acids. Recombinant Ec-TCTP (rEc-TCTP) was expressed in Escherichia BL21 (DE3) and purified for mouse anti-Ec-TCTP serum preparation. The rEc-TCTP fusion protein was demonstrated to possess antioxidant activity, which conferred resistance to H(2)O(2) damage. Quantitative real-time PCR analysis revealed that Ec-TCTP mRNA is predominately expressed in the liver, and the expression was up-regulated in the liver of grouper after viral challenge with Singapore grouper iridovirus (SGIV). Intracellular localization revealed that Ec-TCTP expression was distributed predominantly in the cytoplasm. Although human TCTP has a role in apoptosis regulation, it is not known if grouper TCTP has any role in apoptosis regulation. Strikingly, grouper TCTP, when overexpressed in fathead minnow (FHM) cells, protected them from cell death induced by cycloheximide (CHX). In addition, overexpressed Ec-TCTP in grouper spleen (GS) cells inhibited the replication of SGIV. These results suggest that Ec-TCTP may play a critical role in their response to SGIV infection, through regulation of a cell death pathway that is common to fish and humans.
翻译控制肿瘤蛋白（TCTP）是一种参与多种生物学过程的重要分子，如细胞生长、细胞周期进程、恶性转化和增强抗细胞凋亡活性。本研究克隆并鉴定了卵形鲷（Epinephelus coioides）的 TCTP（Ec-TCTP）。Ec-TCTP 的全长 cDNA 由 1057bp 组成，其中 510bp 为开放阅读框，编码一个由 170 个氨基酸组成的假定蛋白。重组 Ec-TCTP（rEc-TCTP）在大肠杆菌 BL21（DE3）中表达并纯化，用于制备小鼠抗 Ec-TCTP 血清。rEc-TCTP 融合蛋白表现出抗氧化活性，可赋予其抵抗 H2O2 损伤的能力。定量实时 PCR 分析显示，Ec-TCTP mRNA 主要在肝脏中表达，在卵形鲷感染新加坡石斑鱼虹彩病毒（SGIV）后肝脏中表达上调。细胞内定位显示 Ec-TCTP 表达主要分布在细胞质中。尽管人类 TCTP 在凋亡调控中发挥作用，但尚不清楚鱼类 TCTP 是否在凋亡调控中发挥作用。值得注意的是，在胖头鲦（FHM）细胞中过表达鱼类 TCTP 可保护其免受环己酰亚胺（CHX）诱导的细胞死亡。此外，在卵形鲷脾脏（GS）细胞中过表达 Ec-TCTP 可抑制 SGIV 的复制。这些结果表明，Ec-TCTP 可能通过调节鱼类和人类共有的细胞死亡途径，在其对 SGIV 感染的反应中发挥关键作用。
