Qiu Jianming, Cheng Fang, Yoto Yuko, Zádori Zoltán, Pintel David
Department of Molecular Microbiology and Immunology, Life Sciences Center, University of Missouri--Columbia, 65211, USA.
J Virol. 2005 Sep;79(17):11035-44. doi: 10.1128/JVI.79.17.11035-11044.2005.
The RNA transcription profile of the goose parvovirus (GPV) was determined, and it is a surprising hybrid of features of the Parvovirus and Dependovirus genera of the Parvovirinae subfamily of the Parvoviridae. Similar to the Dependovirus adeno-associated virus type 5, RNAs transcribed from the GPV upstream P9 promoter, which encode the viral nonstructural proteins, were polyadenylated at a high efficiency at a polyadenylation site [(pA)p] located within an intron in the center of the genome. Efficient usage of (pA)p required a downstream element that overlaps with the polypyrimidine tract of the A2 3' splice site of the central intron. An upstream element required for efficient use of (pA)p was also identified. RNAs transcribed from the P42 promoter, presumed to encode the viral capsid proteins, primarily extended through (pA)p and were polyadenylated at a site, (pA)d, located at the right end of the genome and ultimately spliced at a high efficiency. No promoter analogous to the Dependovirus P19 promoter was detected; however, similar to minute virus of mice and other members of the Parvovirus genus, a significant portion of pre-mRNAs generated from the P9 promoter were additionally spliced within the putative GPV Rep1 coding region and likely encode an additional, smaller, nonstructural protein. Also similar to members of the Parvovirus genus, detectable activity of the GPV P42 promoter was highly dependent on transactivation by the GPV Rep1 protein in a manner dependent on binding to a cis-element located in the P42 promoter.
测定了鹅细小病毒(GPV)的RNA转录谱,它是细小病毒科细小病毒亚科细小病毒属和依赖病毒属特征的惊人混合体。与依赖病毒5型腺相关病毒相似,从GPV上游P9启动子转录的RNA编码病毒非结构蛋白,这些RNA在位于基因组中心一个内含子内的聚腺苷酸化位点[(pA)p]处高效聚腺苷酸化。有效利用(pA)p需要一个下游元件,该元件与中心内含子A2 3'剪接位点的多嘧啶序列重叠。还鉴定了有效利用(pA)p所需的上游元件。从P42启动子转录的RNA推测编码病毒衣壳蛋白,主要延伸通过(pA)p,并在位于基因组右端的一个位点(pA)d处聚腺苷酸化,最终高效剪接。未检测到类似于依赖病毒P19启动子的启动子;然而,与小鼠微小病毒和细小病毒属的其他成员相似,从P9启动子产生的大部分前体mRNA在假定的GPV Rep1编码区内额外剪接,并可能编码一种额外的、较小的非结构蛋白。同样与细小病毒属的成员相似,GPV P42启动子的可检测活性高度依赖于GPV Rep1蛋白的反式激活,其方式依赖于与位于P42启动子中的顺式元件结合。