禽网状内皮组织增生症病毒囊膜蛋白YxxL基序及其突变体病毒的拯救

YxxL Motif in Envelope Protein of Avian Reticuloendotheliosis Virus and Its Mutants Rescuing

禽网状内皮组织增生症病毒(REV)囊膜蛋白Env与病毒感染、复制、致病性密切相关,然其分子基础尚不清楚。本研究对NCBI中不同REV毒株Env序列分析发现,其胞浆区存在一个高保守且可能与病毒致病性有关的酪氨酸基序YxxL。通过定点突变以及分子传染性克隆技术,构建了REV Env蛋白YxxL基序2个突变体(Y突变为F,L突变为A)。通过转染DF1细胞,并经间接免疫荧光以及测序鉴定,拯救并获得了2个REV突变体病毒,分别命名为FxxL、YxxA。Env蛋白中YxxL保守基序的发现以及相应突变体病毒的拯救为研究REV Env蛋白及其YxxL基序在REV致病中分子作用基础提供了材料。

The envelope protein （Env）of avian reticuloendotheliosis virus （REV）plays vital roles in viral infection, replication and pathogenesis. In this study, we analyzed all Env sequences of REV deposited in NCBI and found that a highly conserved tyrosine-based motif YxxL was located in the cytoplasmic tail of Env. Two YxxL mutations （Y to F and L to A respectively） in infectious clone SNV were constructed by site mutation,and two mutants （named FxxL and YxxA respectively） were rescued by transfection with the corresponding SNV infectious clones in DF1 cells. The rescuing of REV mutants FxxL and YxxA were confirmed by indirect immunofluorescence assay and sequencing. The finding of YxxL motif in REV Env and the rescued two YxxL mutants could pave the way for further elucidation of the roles and molecular mechanism of Env in REV infection and pathogenesis.