Jansen K A, Wolfs C J, Lohuis H, Goldbach R W, Verduin B J
Department of Virology, Wageningen Agricultural University, Binnenhaven, The Netherlands.
Virology. 1998 Mar 15;242(2):387-94. doi: 10.1006/viro.1997.9000.
The biochemical and functional properties of the movement protein (MP) of brome mosaic virus (BMV) were investigated. Expression and purification of the BMV MP from Escherichia coli resulted in a pure and soluble protein preparation. Sucrose gradient centrifugation revealed that BMV MP forms oligomers consisting of two or more copies but no higher order multimers even when different ionic strengths and pHs were applied. Nitro-cellulose filter binding and gel retardation studies showed that in vitro the BMV MP preferentially bound to ss nucleic acids (RNA and DNA); the affinity to ssRNA was lower compared to BMV coat protein. The binding to ss nucleic acid was cooperative and not sequence specific and the hypothetical binding site was calculated to be around three to six nucleotides per MP monomer. The nucleic acid binding properties of the BMV MP are discussed in relation to the recent finding that this protein is also able to form tubular structures in infected protoplasts.
对雀麦花叶病毒（BMV）运动蛋白（MP）的生化和功能特性进行了研究。从大肠杆菌中表达并纯化BMV MP，得到了一种纯的可溶性蛋白制剂。蔗糖梯度离心显示，即使应用不同的离子强度和pH值，BMV MP也形成由两个或更多拷贝组成的寡聚体，但没有更高阶的多聚体。硝酸纤维素滤膜结合和凝胶阻滞研究表明，在体外BMV MP优先结合单链核酸（RNA和DNA）；与BMV外壳蛋白相比，其对单链RNA的亲和力较低。与单链核酸的结合是协同性的且不具有序列特异性，据计算每个MP单体的假设结合位点约为三到六个核苷酸。结合最近发现该蛋白在受感染的原生质体中也能形成管状结构，对BMV MP的核酸结合特性进行了讨论。
