| 摘要: |
| 为了明确脊尾白虾维甲酸X受体基因在环境胁迫和蜕皮周期中的作用，本研究通过RACE技术克隆了脊尾白虾（Exopalaemon carinicauda）维甲酸X受体cDNA全长，命名为EcRXR基因，该cDNA序列全长为1323 bp，开放阅读框（ORF）为855 bp，编码一个284个氨基酸组成的蛋白质，分子量为30.918 kDa，理论等电点为PI为6.788；EcRXR基因推导氨基酸序列经Blastp在线比对分析显示，EcRXR与已知甲壳动物RXR的同源性为71%—90%；系统进化树分析结果显示，脊尾白虾EcRXR的氨基酸序列与日本沼虾RXR的氨基酸序列聚为一支。荧光定量RT-PCR分析表明，EcRXR基因在各组织中均有表达，而在眼柄相对表达量较高，血淋巴中最低。EcRXR基因在蜕皮周期中的表达规律表明，EcRXR基因表达在不同蜕皮时期存在明显变化，在眼柄、肝胰腺、胃和肠中整体呈现上升趋势，在鳃中呈现先下降后上升的趋势，在表皮中呈现逐渐降低的趋势。EcRXR基因在温度、盐度胁迫过程中的表达规律分析结果发现，温度、盐度胁迫均可显著改变EcRXR基因在鳃和肝胰腺中的表达模式，温度胁迫下EcRXR基因在鳃中呈先上升后下降的表达趋势，肝胰腺中整体呈先上升后下降再上升再下降的表达趋势；盐度对鳃和肝胰腺的调控模式相同，均呈先升高后下降的变化趋势。本研究结果表明EcRXR基因在脊尾白虾蜕皮发育、酶活性调控及渗透压调节中发挥重要作用，为深入研究甲壳动物维甲酸X受体基因的功能提供了重要的基础信息。 |
| 关键词: 脊尾白虾 RXR 温度 盐度 蜕皮 基因表达 |
| DOI：10.11693/hyhz20160300065 |
| 分类号: |
| 基金项目:国家虾产业技术体系，CARS-47号；山东省泰山产业领军人才工程项目，LJNY2015002号；国家自然科学基金项目，31472275号。 |
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| CLONING AND EXPRESSION OF RETIONID X RECEPTOR UNDER TEMPERATURE AND SALINITY STRESSES AND MOLTING CYCLES IN EXOPALAEMON CARINICAUDA |
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LIU Fei1,2, LI Jian1,3, LI Ji-Tao1, GE Qian-Qian1, LIAN Chun-Ang1,2, CHANG Zhi-Qiang1
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1.Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China;2.College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai 201306, China;3.Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266235, China
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| Abstract: |
| Retinoid X receptor is an important endogenous regulatory factor for the growth and reproduction of crustacean. We cloned full-length cDNA of a retinoid X receptor in Exopalaemon carinicauda by RACE (rapid amplification of cDNA ends). The full-length cDNA of EcRXR was 1323 bp, containing an open reading frame (ORF) in 855 bp, encoding a 284 amino-acid polypeptide; molecular weight was predicted for 30.918 kDa and isoelectric point estimated for 6.788. The predicted amino acid sequence of EcRXR shared 71%—90% identity with those of other crustaceans as showed in homologous analysis, and EcRXR is clustered with crustaceans RXRs in phylogenetic tree. Homologous analysis showed that EcRXR has the highest homology to RXR of Macrobrachium nipponensis. The quantitative real-time RT-PCR showed that EcRXR gene could be detected in all tested tissues of E. carinicauda. And the eyestalk is in highest expression level, hemolymph in lowest, and the other six tissues in-between. During the molting cycle, the expression of EcRXR gene in eyestalk, hepatopancreas, stomach and intestine, kept rising. However, in gill, fell first, then rose. Andin cuticle kept falling. After challenged by temperature and salinity, the expressions of EcRXR gene in gill and hepatopancreas of E. carinicauda showed different trends. The expressions of EcRXR gene in gill rose first, then fell under temperature stress; the expressions of EcRXR gene in hepatopancreas increased after the first drop rise again under salinity stress. Analysis of the moulting cycle, temperature and salinity stimulation provided further evidence that EcRXR played pivotal roles during molting in osmotic regulation. Future investigations should focus on the functions of RXR in E. carinicauda and other crustaceans. |
| Key words: Exopalaemon carinicauda retinoid X receptor (RXR) temperature salinity molting gene expression |
