【摘要】 NDV的P基因能够通过RNA编辑机制编码3种病毒蛋白P、V和W。为了初步确定新城疫病毒P、V和W的功能结构域及其在P基因中位置,对这3种具有相同N端不同C端的病毒蛋白进行生物信息学分析。分别设计针对基因Ⅱ、Ⅲ、Ⅳ和Ⅶ型以及class Ⅰ NDV毒株P基因的引物。RT-PCR获得5种基因型NDV P基因的正确序列。通过核苷酸序列预测P基因表达产物的氨基酸序列,并进行二级结构预测和三级结构模拟。将SV5 V蛋白空间结构作为模板,从而分析获得了NDVP/V/W基因编码产物的二级结构以及部分空间结构。综合各种分析数据,预测P蛋白辅助N蛋白折叠的结构域位于N端前50 aa内;介导P蛋白四聚体形成的coiled-coil结构位于221-290 aa范围内;介导P蛋白与基因组的作用的X结构域位于291-392 aa范围内。V蛋白的C端结构域的编码区域位于P蛋白132-239 aa编码区域内。更多还原

【Abstract】 Newcastle disease virus(NDV)P gene could encode three viral proteins,P,V and W by inserting one or two G residues at the conserved editing locus.In order to located the functional domains of the P,V and W protein of NDV,fragments of P gene from NDV strains belonging to genotype Ⅱ,Ⅲ,VIa,VIId and class Ⅰ were amplified with 5 pairs of specific primers.Based on sequencing results,the amino acid sequences of P gene-coded proteins were predicted,and sent to internet for second structure prediction and modeling.Structural investigations on the P gene-encoded proteins showed that an α-helix in the phosphoprotein N-terminal domain(PNT)from 20 to 29 aa was identified,which was reported to be a chaperone for newly synthesized N,and prevent it from bingding to non-viral RNA in the infected cells;the putative oligomerization domain(PMD)was in the region between 221 aa and 290 aa;the putative C-terminal sub-domain of X domain was found beween 291 aa and 392 aa,which was proved to be a N:RNA-binding domain of Paramyxovirus;the C-terminal domain(CTD)of V protein was found beween 132 aa and 239 aa,partially overlapping with PMD.更多还原