Tripartite motif (TRIM) family proteins are named by the presence of tripartite motifs in their amino terminal domains. Apart from the amino terminal, their carboxyl terminal contain variable domains which mediate diverse functions of the TRIM proteins. It had been found that TRIM proteins played important roles in distinct biological processes, such as innate immunity, anti-tumor immunity, cell cycle regulation and so on. In the present study, we cloned a TRIM32 (LvTRIM32) gene from Litopenaeus vannamei. LvTRIM32 was highly expressed in hemocytes, gills and epidermis, and subcellular localization analysis indicated that it was widely distributed in S2 cells. In vitro ubiquitination assays indicated that LvTRIM32 had E3 ubiquitin ligase activity. Results of real-time RT-PCR assay showed that LvTRIM32 was induced in shrimp hemocytes upon oxidative stress. It was also proved that the promoter activity of LvTRIM32 was enhanced by NF-E2-related factor, and knocked-down expression of LvTRIM32 depressed the expression of malic enzyme and epoxide hydrolase. Downregulated LvTRIM32 suppressed the cumulative mortality of shrimp under oxidative stress. Moreover, it was found that LvTRIM32 could be induced in shrimp hemocytes upon immunostimulation, and downregulated LvTRIM32 increased the cumulative mortality of shrimp infected with white spot syndrome virus (WSSV) or Vibrio alginolyticus. Collecting results suggested that LvTRIM32 was a member of shrimp antioxidant stress system, and it was also involved in WSSV- or V. alginolyticus-infection resistance.

三方基序（TRIM）家族蛋白的命名是在其氨基末端结构域中存在三方基序。除氨基末端外，它们的羧基末端还包含介导TRIM蛋白各种功能的可变域。已经发现TRIM蛋白在不同的生物学过程中起重要作用，例如先天免疫，抗肿瘤免疫，细胞周期调控等。在本研究中，我们从南美白对虾中克隆了一个TRIM32（LvTRIM32）基因。LvTRIM32在血细胞，腮和表皮中高表达，亚细胞定位分析表明它在S2细胞中广泛分布。体外泛素化试验表明LvTRIM32具有E3泛素连接酶活性。实时RT-PCR测定的结果表明，在氧化应激下，虾血细胞中诱导出LvTRIM32。它也证明了的启动子活性LvTRIM32通过NF-E2相关因子增强，并且被击倒的表达LvTRIM32压下的表达苹果酸酶和环氧化物水解酶。下调的LvTRIM32抑制了虾在氧化胁迫下的累积死亡率。此外，发现在免疫刺激下，虾血细胞中可诱导出LvTRIM32，而LvTRIM32被下调。增加了感染白斑综合症病毒（WSSV）或溶藻弧菌的虾的累积死亡率。收集结果表明，LvTRIM32是虾抗氧化应激系统的成员，并且还参与了WSSV或溶藻弧菌的感染抗性。