Abstract

Myxovirus resistance (Mx) proteins belonging to the dynamin superfamily of high molecular weight GTPases exist in various isoforms and play crucial role in innate immunity. In addition to the isoforms, Mx1 also plays important role in exerting its anti-viral actions against a broad range of animal RNA viruses. In rohu (Labeo rohita), mx1 full-length cDNA sequence consists of 2440 nucleotides (nt) encoding 628 amino acids (aa) polypeptide of 71.289 kDa. Structurally, it belongs to the family of large GTPases with one DYNc domain (13-257aa) comprising of dynamin family motifs (LPRGSGIVTR) and the tripartite GTP-binding motifs (GDQSSGKS, DLPG and TKPD) at the N-terminal and one GED domain (537-628aa) at C-terminus. Rohu Mx1 is closely related to zebrafish Mx1 and is widely expressed in gill, liver, kidney, spleen and blood. In response to rhabdovirus vaccinations, poly I:C stimulation and bacterial infections, mx1 gene expression in rohu was significantly (p < 0.05) induced in majority of the tested organs/tissues. Stimulation of rohu gill cell line with bacterial RNA also induced mx1 gene expression. Together these data suggest the important role of Mx1 in innate immunity in rohu against wide spectrum of fish pathogens.

摘要

粘液病毒抗性 (Mx) 蛋白属于高分子量 GTP 酶的动力蛋白超家族，以多种亚型存在，在先天免疫中起关键作用。除了同种型之外，Mx1 在针对多种动物 RNA 病毒发挥其抗病毒作用方面也发挥着重要作用。在罗胡 ( Labeo rohita)中，mx1 个全长 cDNA 序列由 2440 个核苷酸 (nt) 组成，编码 628 个氨基酸 (aa) 的 71.289 kDa 多肽。在结构上，它属于大型 GTP 酶家族，具有一个 DYNc 结构域 (13-257aa)，由 N 端的动力蛋白家族基序 (LPRGSGIVTR) 和三方 GTP 结合基序 (GDQSSGKS、DLPG 和 TKPD) 和一个 GED 结构域组成(537-628aa) 在 C 端。Rohu Mx1与斑马鱼Mx1密切相关，广泛表达于鳃、肝、肾、脾和血液中。作为对弹状病毒疫苗接种、poly I:C 刺激和细菌感染的反应， 在大多数测试的器官/组织中，rohu 中的mx 1 基因表达被显着诱导 ( p < 0.05)。用细菌RNA刺激rohu鳃细胞系也诱导mx1 基因表达。这些数据共同表明 Mx1 在 rohu 对广谱鱼类病原体的先天免疫中的重要作用。