Kosukegawa A, Arisaka F, Takayama M, Yajima H, Kaidow A, Handa H
Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Midori-ku-Yokohama, Japan.
Biochim Biophys Acta. 1996 May 21;1290(1):37-45.
Three capsid proteins of SV40 (VP1, VP2, and VP3) were expressed in insect cells using recombinant baculoviruses. When the VP1 capsid protein was expressed alone or co-expressed with VP2 and VP3, virus-like particles (VLP) were produced. In the latter case, the minor capsid proteins, VP2 and VP3, were incorporated into the VLP. VLPs with and without VP2 and VP3, and the wild type SV40 virions were indistinguishable under electron microscope. The sedimentation coefficient, S20,w' obtained for the VLP consisting of VP1 alone (VP1-VLP) was 170 S, and that for the VLP consisting of all of the capsid proteins (VP1/2/3-VLP) was 174 S. Treatment of the VP1-VLP with a calcium ion chelating agent and a reducing agent caused dissociation of the VP1-VLP. The dissociated and purified VP1 proteins were identified as pentamers of VP1 based on the molecular weight determination by sedimentation equilibrium. The pentamers were shown to possess the ability to re-assemble into VLP which had the S20,w of 141S. The results are discussed in relation to the morphogenesis of SV40.
使用重组杆状病毒在昆虫细胞中表达了猴空泡病毒40（SV40）的三种衣壳蛋白（VP1、VP2和VP3）。当单独表达VP1衣壳蛋白或与VP2和VP3共表达时，会产生病毒样颗粒（VLP）。在后一种情况下，次要衣壳蛋白VP2和VP3被整合到VLP中。在电子显微镜下，含有和不含有VP2和VP3的VLP以及野生型SV40病毒粒子无法区分。仅由VP1组成的VLP（VP1-VLP）的沉降系数S20,w'为170 S，而由所有衣壳蛋白组成的VLP（VP1/2/3-VLP）的沉降系数为174 S。用钙离子螯合剂和还原剂处理VP1-VLP会导致VP1-VLP解离。基于沉降平衡法测定的分子量，解离并纯化的VP1蛋白被鉴定为VP1五聚体。这些五聚体显示出重新组装成沉降系数为141S的VLP的能力。结合SV40的形态发生对结果进行了讨论。
