东北七鳃鳗肠道应答气单胞菌免疫刺激相关蛋白的鉴定

动物肠道中寄生的微生物与宿主的营养、免疫及防御功能密切相关。本研究在东北七鳃鳗肠道中分离获得一株优势细菌，并鉴定为气单胞菌属（Aeromonads sp.）。建立了荧光定量PCR快速检测气单胞菌拷贝数的方法，经poly(I∶C)刺激后，气单胞菌数量下降115倍。因此，该肠道气单胞菌被认为是七鳃鳗肠道适应性免疫系统进化的关键菌群之一。为了进一步分析气单胞菌对东北七鳃鳗肠道适应性免疫影响的分子机制，将分离菌株腹腔注射七鳃鳗，利用双向电泳技术鉴定了七鳃鳗肠道应答气单胞菌免疫刺激的相关蛋白。共鉴定19个差异表达蛋白质，其中12个蛋白质表达上调，5个蛋白质表达下调，1个蛋白质刺激后消失，1个新增蛋白质，并对蛋白质功能进行分类。七鳃鳗肠道应答气单胞菌免疫刺激的差异表达蛋白分别参与了七鳃鳗适应性免疫调控、信号转导及能量代谢等。该研究可拓宽对七鳃鳗免疫研究的途径，为深入探讨适应性免疫系统发育提供理论基础和新的研究思路。

Identification of Protein Involved in Lamprey Gut Response of Aeromonas Immunostimulation

Microflora harboring in the digestive system play important role in the nutrition, immune response, and defense functions of animals. A bacteria strain was isolated from intestine of Lampetra morii. This strain was identified as Aeromonas sp. after sequencing its 16S rDNA fragment. The fluorescent quantitative PCR(qPCR) method for rapid detection of Aeromonas strain copy numbers was constructed. The copy number of Aeromonas strain decreased by 115 times after stimulation by poly(I:C) for 24 h compared with PBS treatment. Therefore, the isolated Aeromonas strain was considered to be one of the key intestinal symbiotic essential for evolution of the lamprey adaptive immune system. By using 2 D electrophoresis (2 DE) in the analysis of Aeromonas induced intestine proteome,thirteen up-regulated,three down regulated, two vanished, and one newly emerging protein were identified. All of the identified proteins could be classified into different groups according to their predicted functions. As one of the key microbes in lamprey intestine, Aeromonas could induce differential expression of protein involved in lamprey gut response. The characterized proteins were predicted to be involved in lamprey adaptive immunity regulation, signal transduction, and energy metabolism. This study could provide theoretical support for analyzing the interaction between the intestinal symbiotic bacteria and the intestinal immune system of lamprey.