Bauer Anja, Neumann Sebastian, Karger Axel, Henning Ann-Kristin, Maisner Andrea, Lamp Boris, Dietzel Erik, Kwasnitschka Linda, Balkema-Buschmann Anne, Keil Günther M, Finke Stefan
Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Molecular Biology, Greifswald - Insel Riems, Germany.
Institute of Virology, Philipps-University Marburg, Marburg, Germany.
PLoS One. 2014 May 13;9(5):e97233. doi: 10.1371/journal.pone.0097233. eCollection 2014.
Membrane envelopment and budding of negative strand RNA viruses (NSVs) is mainly driven by viral matrix proteins (M). In addition, several M proteins are also known to be involved in host cell manipulation. Knowledge about the cellular targets and detailed molecular mechanisms, however, is poor for many M proteins. For instance, Nipah Virus (NiV) M protein trafficking through the nucleus is essential for virus release, but nuclear targets of NiV M remain unknown. To identify cellular interactors of henipavirus M proteins, tagged Hendra Virus (HeV) M proteins were expressed and M-containing protein complexes were isolated and analysed. Presence of acidic leucine-rich nuclear phosphoprotein 32 family member B (ANP32B) in the complex suggested that this protein represents a direct or indirect interactor of the viral matrix protein. Over-expression of ANP32B led to specific nuclear accumulation of HeV M, providing a functional link between ANP32B and M protein. ANP32B-dependent nuclear accumulation was observed after plasmid-driven expression of HeV and NiV matrix proteins and also in NiV infected cells. The latter indicated that an interaction of henipavirus M protein with ANP32B also occurs in the context of virus replication. From these data we conclude that ANP32B is a nuclear target of henipavirus M that may contribute to virus replication. Potential effects of ANP32B on HeV nuclear shuttling and host cell manipulation by HeV M affecting ANP32B functions in host cell survival and gene expression regulation are discussed.
负链RNA病毒（NSV）的膜包裹和出芽主要由病毒基质蛋白（M）驱动。此外，已知几种M蛋白也参与宿主细胞调控。然而，对于许多M蛋白，其细胞靶点和详细分子机制尚不清楚。例如，尼帕病毒（NiV）的M蛋白通过细胞核运输对于病毒释放至关重要，但NiV M的核靶点仍然未知。为了鉴定亨尼帕病毒M蛋白的细胞相互作用分子，表达了带有标签的亨德拉病毒（HeV）M蛋白，并分离和分析了含M的蛋白复合物。复合物中存在富含酸性亮氨酸的核磷蛋白32家族成员B（ANP32B），表明该蛋白代表病毒基质蛋白的直接或间接相互作用分子。ANP32B的过表达导致HeV M在细胞核中特异性积累，为ANP32B与M蛋白之间提供了功能联系。在质粒驱动表达HeV和NiV基质蛋白后以及在NiV感染的细胞中均观察到了ANP32B依赖性的核积累。后者表明亨尼帕病毒M蛋白与ANP32B的相互作用也发生在病毒复制过程中。从这些数据我们得出结论，ANP32B是亨尼帕病毒M的核靶点，可能有助于病毒复制。文中还讨论了ANP32B对HeV核穿梭的潜在影响以及HeV M通过影响ANP32B在宿主细胞存活和基因表达调控中的功能对宿主细胞的调控作用。
