YXXM基序对J亚群禽白血病病毒复制的影响  

Effect of YXXM motif on viral replication of subgroup J avian leukosis virus

作　　者：冯少珍[1] 李娇[1] 曹伟胜[1] 廖明[1] 

机构地区：[1]华南农业大学兽医学院,农业部动物疫病防控重点开放实验室,广州510642

出　　处：《微生物学报》2011年第12期1663-1668,共6页Acta Microbiologica Sinica

基　　金：NSFC-广东联合基金(U0831002);国家博士后科学基金(20100470929);广东省自然科学基金(10451064201005432);广东省科技计划项目(2009A020101006);国家自然科学基金(30771612)~~

摘　　要：【目的】毒株NX0101是骨髓瘤病变型J亚群禽白血病病毒,其早期感染细胞能诱导PI3K/Akt信号转导通路的激活,本文针对NX0101毒株是否存在YXXM基序及其作用进行了探讨。【方法】利用TMpred软件对NX0101毒株囊膜蛋白(Env)的氨基酸序列进行生物信息学分析,通过搭桥PCR方法将YXXM基序相应的核苷酸序列突变后,构建突变质粒并转染DF-1细胞,拯救出YXXM突变体毒株NX0101mt(Y/F,M/A),利用real-time PCR和ELISA方法检测并比较YXXM突变前后毒株在RNA水平和蛋白水平的复制情况。【结果】NX0101毒株Env胞浆区554-557位氨基酸存在典型的PI3K结合基序YXXM。YXXM基序突变后,病毒RNA转录水平和病毒蛋白合成水平都显著下降。【结论】YXXM基序对NX0101毒株在体外宿主细胞中复制发挥重要的作用。[Objective] It was reported that subgroup J avian leukosis virus strain NX0101 activates PI3K/Akt pathway during early infection in DF-1 cells.Whether there is YXXM motif in the amino acid sequence of NX0101 and the function of YXXM motif were studied.[Methods] The presence of internal transmembrane domains in the envelope protein of NX0101 was analyzed by Tmpred.Point mutation was introduced to change the YXXM motif in the NX0101 strain to FXXA.The plasmid containing the full genome of NX0101 with mutation within the YXXM motif in pMD18-T vector was constructed and transfected into DF-1 cells.Viral replication levels of NX0101 strain and the mutation one were tested and compared by real-time PCR and ELISA.[Results] The amino acid sequence of NX0101 strain had one YXXM motif（amino acids 554-557） in the cytoplasmic tail of envelope protein.The mutated NX0101 strain（Y554F,M557A） was rescued by reverse genetics technique.Viral replication of the mutated NX0101 strain was significantly lower than that of NX0101 strain in the level of either RNA or protein synthesis.[Conclusion] The results revealed that the YXXM motif was important for virus NX0101 replication in DF-1 cells.

关 键 词：J亚群禽白血病病毒 病毒NX0101 YXXM基序 病毒复制 

分 类 号：S852.65[农业科学—基础兽医学]