Lusa S, Garoff H, Liljeström P
Department of Molecular Biology, Karolinska Institute, Huddinge, Sweden.
Virology. 1991 Dec;185(2):843-6. doi: 10.1016/0042-6822(91)90556-q.
The Semliki Forest virus directs the synthesis of three virus-specific transmembrane proteins p62, 6K, and E1, which all are made in equimolar amounts from a polyprotein precursor molecule. The p62 and E1 spike proteins form heterodimeric complexes in the endoplasmic reticulum before being transported to the cell surface where virus budding occurs. In this study we show that the 6K protein becomes associated to the p62E1 complex in the endoplasmic reticulum and transported with the complex to the cell surface. During virus budding, E1 and p62 (which has matured into the E2 protein) are incorporated into new virions whereas the 6K is mostly excluded. Virus particles released from infected BHK cells contain only about 3% of 6K in their membrane as compared to the spike protein content. The relevance of these findings for the mechanism of SFV assembly is discussed.
Semliki森林病毒指导合成三种病毒特异性跨膜蛋白p62、6K和E1，它们均由一个多蛋白前体分子以等摩尔量合成。p62和E1刺突蛋白在内质网中形成异二聚体复合物，然后被转运到发生病毒出芽的细胞表面。在本研究中，我们表明6K蛋白在内质网中与p62E1复合物结合，并与该复合物一起转运到细胞表面。在病毒出芽过程中，E1和p62（已成熟为E2蛋白）被整合到新的病毒粒子中，而6K大多被排除在外。与刺突蛋白含量相比，从感染的BHK细胞释放的病毒颗粒在其膜中仅含有约3%的6K。讨论了这些发现与SFV组装机制的相关性。
