不同品系肉鸡Gimap5基因的表达与功能

Expression and function characterization of Gimap5 gene from different breeds of broilers

摘要:

GTP酶免疫相关蛋白5 (GTPase immune-associated protein 5, Gimap5) 参与T细胞稳态调控，在免疫和炎性反应等过程中发挥重要作用，但其在禽类中的功能与特性研究未见报道。文中以AA+肉鸡和三黄鸡为模式动物，利用RT-PCR克隆Gimap5基因全长编码序列并进行生物信息学分析，RT-qPCR技术分析Gimap5基因的组织表达分布特性及其在炎症反应中的功能特性。AA+肉鸡和三黄鸡Gimap5基因全长编码序列均为771 bp，编码256个氨基酸，在不同物种间保守性较低。Gimap5蛋白N-末端AIG-1结构域和C-末端跨膜序列的α-螺旋结构分别在蛋白功能和细胞定位中可能发挥重要作用。Gimap5基因在AA+肉鸡和三黄鸡各组织中均有表达且变化规律相似，但两品系鸡之间或同一品系鸡不同组织间表达活性存在差异。在炎症反应中，Gimap5基因在血和肝脏中活性均显著下调 (P<0.05)，而在法氏囊中显著上调 (P<0.01)。推测Gimap5是一个参与机体发育和炎症免疫反应的多功能基因，并具有炎症反应诊断标记物的潜在应用价值。

Abstract:

GTPase immune-associated protein 5 (Gimap5), a key factor in maintaining T cell homeostasis, plays important roles in immune and inflammatory processes. However, its function and characteristics in poultry have not been reported. In this study, AA+ and Sanhuang broilers were used as models. The full-length coding sequence of the Gimap5 gene was cloned by RT-PCR and analyzed using bioinformatic methods. Tissue expression and distribution characteristics of the Gimap5 gene and its functional characteristics in inflammatory response were analyzed by RT-qPCR, respectively. The full-length coding sequences of the Gimap5 gene from AA+ and Sanhuang broilers were 771 bp, encoding 256 amino acids, and presented low conservative among different species. The AIG-1 domain of N-terminal and alpha-helix structure of C-terminal transmembrane sequence of might play important roles in the Gimap5 protein function and cell localization, respectively. The Gimap5 gene was widely distributed and expressed in various tissues and the pattern of its expression change was basically similar between AA+ and Sanhuang broilers. However, there were some differences in expression activity between the two breeds or various tissues of the same breed. In inflammatory response, the expression activities of the Gimap5 gene were down-regulated in blood and liver (P<0.05), but up-regulated in the bursa of Fabricius (P<0.01). It is speculated that Gimap5 is a multifunctional gene involved in the development of the body and inflammatory response, and has potential application value for diagnostic marker of inflammatory response.