罗氏沼虾TLRs基因表达差异分析

【目的】探究罗氏沼虾Toll样受体(TLRs)基因(MrToll1、MrToll2和MrToll3)在不同组织中及感染溶藻弧菌(Vibrio alginolyticus)后不同时间鳃组织的表达量差异变化,为揭示罗氏沼虾TLRs在应对病害等免疫方面的表现和作用机理提供参考依据。【方法】利用实时荧光定量RT-PCR分别检测MrToll1、MrToll2和MrToll3基因在罗氏沼虾肌肉、鳃、肝胰腺、心脏、胃、肠、血淋巴、神经节、眼柄等不同组织中的相对表达量,并以同样方法检测罗氏沼虾感染溶藻弧菌后TLRs基因的相对表达量变化情况。【结果】罗氏沼虾MrToll1、MrToll2和MrToll3基因在各组织中广泛表达,但存在组织表达差异性。MrToll1和MrToll2基因在鳃组织中的相对表达量最高,分别是在肝胰腺中相对表达量的19.26和20.03倍;MrToll3基因在神经节中的相对表达量最高,是在肝胰腺中的10.13倍。感染溶藻弧菌悬液后,罗氏沼虾死亡率随时间的推移不断升高,至注射感染72 h时死亡率达峰值(64%),随后不再出现死亡。感染溶藻弧菌后罗氏沼虾MrToll1基因表达量呈先升高后下降的变化趋势,注射感染后24 h的表达量达峰值;Mrtoll2基因表达量呈下降—升高—下降—升高的波动变化趋势,注射感染后24 h的表达量达峰值;MrToll3基因表达量急剧下降,且维持在较低水平。【结论】罗氏沼虾MrToll1基因是鳃组织抵御细菌感染的主要应答基因,MrToll2基因可能参与鳃组织的其他免疫活动,MrToll3基因的调控机制尚未清晰。

Differential expression of TLRs gene in Macrobrachium rosenbergii

Objective]By analyzing the differential expressions of three Toll-like receptor(TLRs) genes including Mr-Toll1, MrToll2, MrToll3 in different tissues of Macrobrachium rosenbergii and expression difference of gill at different times after infection with Vibrio alginolyticus, the present study provided reference for revealing immune function of M. rosen-bergii TLRs in fighting diseases. Method]Real-time fluorescence quantitative RT-PCR was applied to detect relative ex-pressions of MrToll1, MrToll2 and MrToll3 in muscle, gill, hepatopancreas, heart, stomach, gut, hemolymph, nerve gan-glion, and eyestalk. The same method was also used to test the expression changes of TLRs gene after infected by V. algi-nolyticus. Result]MrToll1, MrToll2 and MrToll3 genes were expressed in all of the tested tissues and there also existed differential expressions. MrToll1 and MrToll2 genes highly expressed in gill among these tissues while the relative expression of MrToll1 and MrToll2 in gill were as much as 19.26 times and 20.03 times as those in hepatopancreases respectively. The expression of MrToll3 gene was the highest in nerve ganglions, which was as 10.13 times as that in hepatopancreases. After infected by V. Alginolyticus, mortality rate of M. rosenbergii increased as time spent, and reached the peak at 72 post infection(64%). After 72 h post infection, no more mortality occurred. After infection with V. alginolyticus, the expression of MrToll1 gene rose first and then decreased, and reached the peak 24 h post infection. The expression of MrToll2 went through a down-up-down-up variation, and reached the maximum 24 h post infection. The expression of MrToll3 gene de-creased sharply and maintained at low level. Conclusion]MrToll1 gene is major response gene for gill resisting bacterial in-fection, MrToll2 gene may be involved in other immune activities of gill, and regulation mechanism of MrToll3 is unknown.