Erlandson Karl J, Bisht Himani, Weisberg Andrea S, Hyun Seong-In, Hansen Bryan T, Fischer Elizabeth R, Hinshaw Jenny E, Moss Bernard
Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA.
Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, NIH, Hamilton, MT 59840, USA.
Cell Rep. 2016 Mar 8;14(9):2084-2091. doi: 10.1016/j.celrep.2016.01.075. Epub 2016 Feb 25.
Poxviruses are enveloped DNA viruses that replicate within the cytoplasm. The first viral structures are crescents and spherical particles, with a lipoprotein membrane bilayer, that are thought to be derived from the ER. We determined that A17, a conserved viral transmembrane protein essential for crescent formation, forms homo-oligomers and shares topological features with cellular reticulon-like proteins. The latter cell proteins promote membrane curvature and contribute to the tubular structure of the ER. When the purified A17 protein was incorporated into liposomes, 25 nm diameter vesicles and tubules formed at low and high A17 concentrations, respectively. In addition, intracellular expression of A17 in the absence of other viral structural proteins transformed the ER into aggregated three-dimensional (3D) tubular networks. We suggest that A17 is a viral reticulon-like protein that contributes to curvature during biogenesis of the poxvirus membrane.
痘病毒是在细胞质内复制的有包膜DNA病毒。最初的病毒结构是新月形和球形颗粒，具有脂蛋白膜双层，被认为源自内质网。我们确定A17是一种对新月形形成至关重要的保守病毒跨膜蛋白，它形成同源寡聚体，并与细胞类网质蛋白具有拓扑学特征。后者这些细胞蛋白促进膜曲率，并有助于内质网的管状结构。当将纯化的A17蛋白掺入脂质体时，分别在低A17浓度和高A17浓度下形成直径25nm的囊泡和小管。此外，在没有其他病毒结构蛋白的情况下，A17在细胞内的表达将内质网转化为聚集的三维（3D）管状网络。我们认为A17是一种病毒类网质蛋白，在痘病毒膜生物发生过程中有助于曲率形成。
