• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >The phiX174 Protein J Mediates DNA Packaging and Viral Attachment to Host Cells.
【24h】

The phiX174 Protein J Mediates DNA Packaging and Viral Attachment to Host Cells.

机译：phiX174 Protein J介导DNA包装和病毒附着在宿主细胞上。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Packaging of viral genomes into their respective capsids requires partial neutralization of the highly negatively charged RNA or DNA. Many viruses, including the Microviridae bacteriophages phiX174, G4, and alpha3, have solved this problem by coding for a highly positively charged nucleic acid-binding protein that is packaged along with the genome. The phiX174 DNA-binding protein, J, is 13 amino acid residues longer than the alpha3 and G4 J proteins by virtue of an additional nucleic acid-binding domain at the amino terminus. Chimeric phiX174 particles containing the smaller DNA-binding protein cannot be generated due to procapsid instability during DNA packaging. However, chimeric alpha3 and G4 phages, containing the phiX174 DNA-binding protein in place of the endogenous J protein, assemble and are infectious, but are less dense than the respective wild-type species. In addition, host cell attachment and native gel migration assays indicate surface variations of these viruses that are controlled by the nature of the J protein. The structure of alpha3 packaged with phiX174 J protein was determined to 3.5A resolution and compared with the previously determined structures of phiX174 and alpha3. The structures of the capsid and spike proteins in the chimeric particle remain unchanged within experimental error when compared to the wild-type alpha3 virion proteins. The amino-terminal region of the phiX174 J protein, which is missing from wild-type alpha3 virions, is mostly disordered in the alpha3 chimera. The differences observed between solution properties of wild-type phiX174, wild-type alpha3, and alpha3 chimera, including their ability to attach to host cells, correlates with the degree of order in the amino-terminal domain of the J protein. When ordered, this domain binds to the interior of the viral capsid and, thus, might control the flexibility of the capsid. In addition, the properties of the phiX174 J protein in the chimera and the results of mutational analyses suggest that an evolutionary correlation may exist between the size of the J protein and the stoichiometry of the DNA pilot protein H, required in the initial stages of infection. Hence, the function of the J protein is to facilitate DNA packaging, as well as to mediate surface properties such as cell attachment and infection.
机译：将病毒基因组包装到它们各自的衣壳中需要部分中和高度带负电荷的RNA或DNA。许多病毒，包括Microviridae噬菌体phiX174，G4和alpha3，都通过编码与基因组包装在一起的带高度正电荷的核酸结合蛋白来解决此问题。 phiX174 DNA结合蛋白J比氨基3和G4 J蛋白长13个氨基酸残基，这是因为在氨基末端有一个额外的核酸结合结构域。由于DNA包装过程中衣壳的不稳定性，无法生成包含较小DNA结合蛋白的嵌合phiX174颗粒。但是，含有phiX174 DNA结合蛋白代替内源性J蛋白的嵌合alpha3和G4噬菌体可以组装并具有传染性，但密度不如相应的野生型物种。此外，宿主细胞附着和天然凝胶迁移试验表明这些病毒的表面变异受J蛋白的性质控制。确定用phiX174 J蛋白包装的alpha3的结构分辨率为3.5A，并与先前确定的phiX174和alpha3的结构进行比较。与野生型α3病毒体蛋白相比，嵌合颗粒中衣壳蛋白和突突蛋白的结构在实验误差范围内保持不变。 phiX174 J蛋白的氨基末端区域在野生型alpha3病毒体中缺失，大部分在alpha3嵌合体中无序。在野生型phiX174，野生型alpha3和alpha3嵌合体的溶液性质之间观察到的差异（包括它们与宿主细胞的附着能力）与J蛋白氨基末端结构域的有序度相关。订购时，该结构域与病毒衣壳内部结合，因此可以控制衣壳的柔性。此外，phiX174 J蛋白在嵌合体中的特性和突变分析结果表明，在感染初期，J蛋白的大小与DNA引导蛋白H的化学计量之间可能存在进化相关性。 。因此，J蛋白的功能是促进DNA包装以及介导诸如细胞附着和感染的表面特性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号