Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Insel Riems, Germany.
Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Insel Riems, Germany.
Virology. 2018 Mar;516:46-54. doi: 10.1016/j.virol.2017.12.034. Epub 2018 Jan 9.
Schmallenberg virus (SBV) induces fetal malformation, abortions and stillbirth in ruminants. While the non-structural protein NSs is a major virulence factor, the biological function of NSm, the second non-structural protein which consists of three hydrophobic transmembrane (I, III, V) and two non-hydrophobic regions (II, IV), is still unknown. Here, a series of NSm mutants displaying deletions of nearly the entire NSm or of the non-hydrophobic domains was generated and the intracellular distribution of NSm was assessed. SBV-NSm is dispensable for the generation of infectious virus and mutants lacking domains II - V showed growth properties similar to the wild-type virus. In addition, a comparable intracellular distribution of SBV-NSm was observed in mammalian cells infected with domain II mutants or wild-type virus. In both cases, NSm co-localized with the glycoprotein Gc in the Golgi compartment. However, domain IV-deletion mutants showed an altered distribution pattern and no co-localization of NSm and Gc.
舍姆贝赫病毒（SBV）可引起反刍动物胎儿畸形、流产和死产。虽然非结构蛋白 NSs 是主要的毒力因子，但由三个疏水性跨膜（I、III、V）和两个非疏水性区域（II、IV）组成的第二非结构蛋白 NSm 的生物学功能仍然未知。在这里，生成了一系列显示几乎整个 NSm 或非疏水性结构域缺失的 NSm 突变体，并评估了 NSm 的细胞内分布。SBV-NSm 对于产生感染性病毒不是必需的，并且缺乏结构域 II-V 的突变体表现出与野生型病毒相似的生长特性。此外，在用结构域 II 突变体或野生型病毒感染的哺乳动物细胞中观察到 SBV-NSm 具有可比的细胞内分布。在这两种情况下，NSm 与糖蛋白 Gc 一起定位于高尔基体区室。然而，结构域 IV 缺失突变体显示出改变的分布模式，并且 NSm 和 Gc 没有共定位。
