斑点叉尾鮰免疫调控相关microRNA功能鉴定与分析

The immune system is fish important defense system which can resist pathogen invasion and infection in order to maintain their own health and stability. MicroRNAs ( miRNA) has been proved to be important regulatory molecules in recent years, and it has been confirmed in human and other animals that miRNAs play crucial roles in regulation of immune processes. These miRNAs also express in the tissues of the fish,but there are few studies on miRNA immune-regulated function in fish. Thus,it is an interesting point to explore miRNA involved in fish immunity regulation. In our finished study, we confirmed the expressions of 9 kinds of miRNA in the immune related tissues of Ictalurus punctatus, and they are most possibolly related to immunity regulation analyzed by bioinformatics methords. In this research, we plan to take the 9 miRNAs above as candidates, and to explore their functions and mechanisms in immunity regulation in Ictalurus punctatus via bioinformatical and miRNA molecular ways. The networks among miRNAs and/or between miRNAs and immunity regulators will also to be concerned. The results of this study will reveal the involvement and there roles of the miRNAs in immune regulation, which will add new and valuble informations for undstanding immune molecular-regulating mechanisms in fish.

免疫系统是鱼类重要的防御系统，能抵御病原生物入侵和感染以维护自身的健康和稳定。microRNAs（miRNA）是近年来发现的重要调控分子，已确证miRNA参与人类和动物的免疫功能调节，并且这些miRNA在鱼类体内同样有表达，但关于miRNA对鱼类免疫调控功能研究报道却较少。因此，揭示miRNA对鱼类免疫功能的调控作用具有重要的学术意义。 本课题组前期研究证实9种miRNA在斑点叉尾鮰免疫相关组织中有表达，初步的生物信息学分析显示它们可能与鱼类的免疫调控有关。本项目拟以上述9种miRNA为研究对象，采用生物信息学、miRNA分子生物学等研究方法，力争从分子、细胞等水平来阐明与鱼类免疫调控相关的9种miRNA作用及机制，以及各种相关分子的网络调控关系。研究的结果将会揭示参与免疫调控的miRNA及其作用，为丰富鱼类免疫调控的分子机制提供新的学术资料。

microRNAs（miRNA）在生命活动中发挥重要调控作用，为揭示miRNA是否参与鱼类免疫调控并鉴定其功能，本项目选择可作为硬骨鱼类免疫系统代表的斑点叉尾鮰为实验动物，采用生物信息学、miRNA分子生物学等研究方法，从分子、细胞和动物等不同层面研究了miRNA在鱼类中免疫调控功能。1.首先采用大肠杆菌脂多糖和β-葡聚糖作为免疫刺激剂处理斑点叉尾鮰，结果发现：免疫刺激剂处理后，9种miRNAs在鱼体主要免疫器官肝脏、脾脏和头肾中的表达均出现不同程度的变化，且相关免疫细胞因子在组织中同样呈现出差异表达。2.为了更全面深入的发掘体内参与免疫抗病相关的关键miRNA，本项目进一步采用大肠杆菌脂多糖和鱼拟态弧菌感染后，构建了斑点叉尾鮰头肾miRNA表达谱，发掘出了更多参与鱼类免疫抗病的miRNAs。3.依据上述的研究结果，筛选出差异显著的2种miRNAs（miR-155和miR-223）进一步进行靶基因预测及调控网络分析。选择miR-155的靶基因SOCS1进行靶基因验证。4. 探讨了miR-155和miR-223的功能，结果发现miR-155和miR-223参与调控鱼类多种免疫细胞因子的表达，表明其在鱼类的免疫调控过程中发挥作用。本研究从不同层面研究了miRNA在鱼类中免疫调控作用并初步探讨了miR-155的调控功能，研究的结果为鱼类miRNA的研究提供了丰富的资料，为深入研究鱼类miRNA的功能提供研究基础，完成了研究内容，达到了预定的研究目标。