1Department of Plant and Environmental Science, Clemson University, Clemson, SC, USA.
2Department of Biological Sciences, Clemson University, Clemson, SC, USA.
J Gen Virol. 2018 Oct;99(10):1444-1452. doi: 10.1099/jgv.0.001132. Epub 2018 Aug 9.
Certain parasitoid wasps are associated with Polydnaviruses, symbiotic viruses that encode virulence factors which are essential to successful parasitization by the wasp of a caterpillar host. Members of one group of Polydnaviruses, the Ichnoviruses, encode a multi-gene family known as Vinnexins. Vinnexins are homologues of insect gap junction genes, and form functional gap junctions that may affect host cell physiology. However, the role of Vinnexins in host pathology and the mechanism by which these affect their caterpillar host are largely unknown. In this article, we generated recombinant baculoviruses to express vinnexins in Spodoptera frugiperda (Sf9) cells. To measure cell physiological changes caused by Vinnexins, cells were probed with a membrane potential-sensitive probe, DiBac4(3), and a pH indicator, carboxyfluorescein diacetate (CFDA). In addition, we utilized carbenoxolone and ouabain, respectively, to probe the role of gap junctions and hemi-channels, and Na+/K+-ATPase in establishing membrane potential in studied cells. Our results indicate that Vinnexins induce cell membrane depolarization and cytoplasmic alkalization to a degree specific to each tested Vinnexin, and that neither Vinnexin hemi-channels nor Na+/K+-ATPase appear to underlie these effects directly. These results hint that members of the Vinnexin protein family may affect host bio-electrical phenomena to disrupt host cell physiology, and that the individual proteins of the family may differentially affect host physiology.
某些寄生蜂与共生病毒 Polydnaviruses 有关，共生病毒编码毒力因子，这些因子对于寄生蜂成功寄生毛毛虫宿主至关重要。Polydnaviruses 中的一组成员，即 Ichnoviruses，编码一个称为 Vinnexins 的多基因家族。Vinnexins 是昆虫间隙连接基因的同源物，形成功能性间隙连接，可能影响宿主细胞的生理学。然而，Vinnexins 在宿主病理学中的作用以及这些因素如何影响它们的毛毛虫宿主在很大程度上尚不清楚。在本文中，我们生成了重组杆状病毒，以在 Spodoptera frugiperda (Sf9) 细胞中表达 vinnexins。为了测量 Vinnexins 引起的细胞生理变化，用膜电位敏感探针 DiBac4(3)和 pH 指示剂羧基荧光素二乙酸酯 (CFDA) 探测细胞。此外，我们分别利用 carbenoxolone 和 ouabain 来探测间隙连接和半通道以及 Na+/K+-ATPase 在研究细胞中建立膜电位的作用。我们的结果表明，Vinnexins 诱导细胞膜去极化和细胞质碱化，程度取决于每个测试的 Vinnexin，并且 Vinnexin 半通道和 Na+/K+-ATPase 似乎都不是这些影响的直接原因。这些结果表明，Vinnexin 蛋白家族的成员可能会影响宿主的生物电现象，从而破坏宿主细胞的生理学，并且该家族的个别蛋白质可能会对宿主生理学产生不同的影响。
