四种水稻蛋白与水稻黑条矮缩病毒编码非结构蛋白P7-2的互作分析

Interaction between four rice proteins and P7-2,an unstructural viral protein encoded by Rice black streaked dwarf virus S7

水稻黑条矮缩病毒(RBSDV)是斐济病毒属的成员之一,可侵染玉米和水稻等作物,给亚洲地区的田间生产带来严重的损失。RBSDV有10条双链RNA(double strand RNA,dsRNA)基因组,编码12个蛋白。其中6个蛋白是病毒粒子的结构成分(P1,P2,P3,P4,P8,P10),6个非结构蛋白分别为P5,P6,P7-1,P7-2,P9-1,P9-2。在非结构蛋白中,P5,P6和P9-1已被证实参与形成毒质结构,P7-1被认为可在细胞质中形成类似管状的结构作为病毒胞间扩散的通道,P7-2和P9-2的功能目前尚不明确。文章采用Pull-Down和液相色谱—质谱联用(LC-MS/MS)等技术来鉴定水稻蛋白(日本晴)与P7-2蛋白间可能存在的互作关系。通过Pull-Down实验分析,发现有4种水稻蛋白可与P7-2相结合,其中2个蛋白为转录相关蛋白,1个为氨基转移酶,还有1个为假定的分子伴侣60前体。实时荧光定量PCR分析显示,感病寄主中的转录相关蛋白和假定的分子伴侣60前体的表达量上调,而氨基转移酶的表达量降低。

Rice black streaked dwarf virus （RBSDV）, a member of the genus Fijivirus, infects maize and rice plants and causes significant yield losses in Asia .RBSDV has a genome of 10 dsRNAs and encodes 12 proteins.Six of these proteins （P1, P2, P3, P4, P8 and P10） are structural components of the viral particle .There are six non-structural proteins, P5, P6, P7-1, P7-2, P9-1, and P9-2.Among those non-structural proteins, P5, P6 and P9-1 have been shown to involve in viroplasm formation and P 7-1 has been identified to form the cytoplasmic tubular-like＆nbsp;structures that serve as a conduit for virion movement between cells .The function of P7-2 and P9-2 is still unknow . In this study , we utilized protein Pull-Down assay and liquid chromatography-tandem mass spectrometry （ LC-MS/MS） techniques to identify the proteins from rice （ Oryza sativa） that interact with P7-2.Four proteins were found to bind P7-2 by Pull-Down assay.Two of them are transcription-associated proteins, one is an aminotransferase and the other one is a putative chaperonin 60 beta precursor .Using real-time quantitative PCR , the transcript expression lev-els of transcription-associated protein and putative chaperonin 60 beta precursor were up-regulated by RBSDV infec-tion.In contrast , the transcript expression of aminotransferase protein was suppressed by RBSDV infection .