咪唑类物质KK-42对日本沼虾α2-巨球蛋白基因表达的影响  

Effect of imidazole derivative KK-42 on expression of α2-macroglobulin in Macrobrachium nipponense

作　　者：王佩[1] 吕黎[1] 张哲亮[1] 吕艳杰[1] 杨洪[1] 宁黔冀[1] 

机构地区：[1]河南师范大学生命科学学院,河南新乡453002

出　　处：《水产学报》2014年第7期913-919,共7页Journal of Fisheries of China

基　　金：国家自然科学基金(30940008);河南省基础与前沿技术研究项目(142300410021)

摘　　要：为探讨KK-42提高感染嗜水气单孢菌的日本沼虾幼虾成活率的机制，实验首次克隆了012M部分序列，研究了α2M基因的时空表达以及KK-42对其表达和活力的影响。将体长3．5-5．0cm的日本沼虾幼虾随机分为2组，分别用1．95×10^-4mol／L的KK-42溶液和不含KK_42的溶液浸泡处理1min，12h后，每组再分为2个亚组，分别向虾腹部注射嗜水气单胞菌菌悬液（菌攻毒实验组和菌攻毒对照组）或生理盐水（实验组-1和对照组-1），于不同时间点测定幼虾的成活率、α2M基因表达水平和活力的变化。结果显示，KK42预处理可显著提高感染嗜水气单胞菌的日本沼虾幼虾成活率。经BLAST比对，克隆的α2M部分mRNA序列与罗氏沼虾α2M具有90％以上同源性。实时荧光定量PCR实验显示，α2M基因表达水平在血细胞中最高，且以蜕皮前期最为显著。KK-42处理的幼虾血细胞012M基因的表达无显著性差异；嗜水气单胞菌刺激使血细胞α2MmRNA水平在3h比0h提高了580％，其活力在24h增幅为47．5％；而菌攻毒实验组mRNA水平在6-48h明显高于菌攻毒对照组，尤其在12h，增幅为511％，其活力水平也呈同样的变化趋势。研究表明，KK-42预处理能上调感染嗜水气单胞菌的幼虾血细胞α2M基因的转录水平，诱导α2M活力增强，这可能增强了幼虾的免疫水平，从而提高成活率。KK-42 pretreatment can promote the survival rate of Macrobrachium nipponense infected with Aeromonas hydrophila. In order to investigate the possible molecular mechanism of KK-42 action,the partial sequence of α2M gene was first cloned and the spatio-temporal expression of the gene as well as the effects of KK-42 on its gene expression and activity were measured. The prawns,3.5 - 5.0 cm long, were soaked for 1 rain in KK-42 solution at a concentration of 1. 95 × 10 ^-4 mol/L （ KK-42 treatment） or 0 （ KK-42 control） ,respectively. The KK-42 treatment group was injected individually with A. hydrophila suspension （KK-42 treatment-A, hydrophila）or saline（ treatment-1 ）into the ventral sinus at 12 h after KK-42 treatment and the KK-42 control group was divided into groups as control-A, hydrophila and control-1, according to the same way. Then the survival rate was surveyed at different time points, and the α2M mRNA level and activity derived from different tissues were measured. Results showed that the survival rate of KK-42 treatment-A, hydrophila dramatically increased by 133% than that of the control-A, hydrophila group. Sequence comparison indicated that the α2M deduced amino acid sequence of M. nipponense had an overall similarity of 90% to that of Macrobrachium rosenbergii. Real-time PCR analysis revealed that α2M was mainly expressed in haemocytes, and higher at premolt. Compared with the KK-42 control group, the changes of α2M mRNA level and activity from KK-42 treatment group were not statistically significant. In control-A. hydrophila group,the α2M gene mRNA level and its activity in haemocytes obviously increased by 580% and 47. 5% , respectively, only at 3 and 24 h post-injection compared to 0 h. In KK-42 treatment-A. hydrophila group, the a2M mRNA transcripts were significantly higher at 6 - 48 h and reached the maximum at 12 h with an increase of 511% than that of control-A, hydrophila group. The change trend of α2M activity was basically similar to that of its expression. In conc

关 键 词：日本沼虾 嗜水气单胞菌 KK-42 α2-巨球蛋白(α2M) 基因表达 

分 类 号：Q459[生物学—生理学] S966.1[农业科学—水产养殖]