Polyomavirus VP1 phosphorylation: coexpression with the VP2 capsid protein modulates VP1 phosphorylation in Sf9 insect cells.
Polyomavirus VP1 phosphorylation: coexpression with the VP2 capsid protein modulates VP1 phosphorylation in Sf9 insect cells.
复制标题
多瘤病毒 VP1 磷酸化：与 VP2 衣壳蛋白共表达可调节 Sf9 昆虫细胞中的 VP1 磷酸化。
DOI：
10.1073/pnas.92.13.5992
复制
发表时间：
1995
影响因子：
11.1
通讯作者：
Garcea,RL
中科院分区：
文献类型：
--
作者：
Li,M;Delos,SE;Montross,L;Garcea,RL
多瘤病毒病毒粒子有一个由72个五聚体VP1蛋白组成的外衣壳，VP1蛋白与次要病毒粒子蛋白VP2和VP3以及病毒小染色体相关。为了研究VP1与VP2/VP3之间的相互作用，我们绘制了VP1磷酸化位点，并利用重组杆状病毒载体将VP1与VP2或VP3共表达后，检测了抗肽抗体对VP1的识别。单独表达或与VP3一起表达的VP1，在多瘤病毒感染小鼠细胞时，其丝氨酸残基不会被修饰。当VP1与VP2共表达时，VP1的非生理性丝氨酸磷酸化降低，含有病毒感染小鼠细胞时修饰的位点Thr-63的色氨酸被磷酸化。一种针对含有Thr-63的VP1 BC环域的抗肽抗体识别了单独表达的VP1，而不是与VP2或VP3共表达的VP1。两种结构蛋白共表达导致的磷酸化变化确定了杆状病毒系统研究蛋白-蛋白相互作用的潜力，并确定了VP1-VP2相互作用的功能作用。
The polyomavirus virion has an outer capsid comprised of 72 pentamers of the VP1 protein associated with the minor virion proteins, VP2 and VP3, and the viral minichromosome. To investigate the interaction between VP1 and VP2/VP3, we mapped VP1 phosphorylation sites and assayed VP1 recognition by anti-peptide antibodies after coexpression of VP1 with VP2 or VP3 by using recombinant baculovirus vectors. VP1, expressed either alone or with VP3, was phosphorylated on serine residues, which are not modified during polyomavirus infection of mouse cells. When VP1 was coexpressed with VP2, the nonphysiologic serine phosphorylation of VP1 was decreased, and a tryptic peptide containing Thr-63, a site modified during virus infection of mouse cells, was phosphorylated. An anti-peptide antibody directed against the VP1 BC loop domain containing Thr-63 recognized VP1 expressed alone but not VP1 coexpressed with VP2 or VP3. The change in phosphorylation resulting from coexpression of two structural proteins identifies the potential of the baculovirus system for studying protein-protein interactions and defines a functional role for the VP1-VP2 interaction.