Mézeth Kjersti B, Nylund Stian, Henriksen Håvard, Patel Sonal, Nerland Audun H, Szilvay Anne Marie
Department of Molecular Biology, University of Bergen, Norway.
Virus Res. 2007 Dec;130(1-2):43-52. doi: 10.1016/j.virusres.2007.05.014. Epub 2007 Jun 28.
Nodaviruses encode an RNA-dependent RNA polymerase called Protein A that is responsible for replication of the viral RNA segments. The intracellular localization of Protein A from a betanodavirus isolated from Atlantic halibut (AHNV) was studied in infected fish cells and in transfected mammalian cells expressing Myc-tagged wild type Protein A and mutants. In infected cells Protein A localized to cytoplasmic structures resembling mitochondria and in transfected mammalian cells the AHNV Protein A was found to co-localize with mitochondrial proteins. Two independent mitochondrial targeting signals, one N-terminal comprising residues 1-40 and one internal consisting of residues 225-246 were sufficient to target both Protein A deletion mutants and enhanced green fluorescent protein (EGFP) to the mitochondria. The N-terminal signal corresponds to the mitochondrial targeting sequence of the Flock House Virus (FHV) Protein A while the internal signal is similar to the single targeting signal previously found in Greasy Grouper Nervous Necrosis Virus (GGNNV) Protein A.
诺达病毒编码一种名为蛋白质A的依赖RNA的RNA聚合酶，该酶负责病毒RNA片段的复制。在感染的鱼类细胞以及表达Myc标签野生型蛋白质A和突变体的转染哺乳动物细胞中，研究了从大西洋大比目鱼中分离出的一种β诺达病毒的蛋白质A的细胞内定位。在感染的细胞中，蛋白质A定位于类似于线粒体的细胞质结构中，而在转染的哺乳动物细胞中，发现AHNV蛋白质A与线粒体蛋白共定位。两个独立的线粒体靶向信号，一个是包含1-40位残基的N端信号，另一个是由225-246位残基组成的内部信号，足以将蛋白质A缺失突变体和增强型绿色荧光蛋白（EGFP）靶向到线粒体。N端信号对应于禽舍病毒（FHV）蛋白质A的线粒体靶向序列，而内部信号类似于先前在脂点黄斑病毒（GGNNV）蛋白质A中发现的单一靶向信号。
