Formation of Sindbis virus capsid protein in mammalian cell-free extracts programmed with viral messenger RNA.
Formation of Sindbis virus capsid protein in mammalian cell-free extracts programmed with viral messenger RNA.
复制标题
在用病毒信使 RNA 编程的哺乳动物无细胞提取物中形成辛德比斯病毒衣壳蛋白。
DOI：
10.1073/pnas.71.5.1843
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发表时间：
1974
影响因子：
11.1
通讯作者：
M. Schlesinger
中科院分区：
文献类型：
--
作者：
R. Cancedda;M. Schlesinger
Extracts from Krebs II ascites cells and rabbit reticulocytes effectively synthesize viral proteins with Sindbis viral mRNA isolated from Sindbis-infected BHK cells. The major product is identical to Sindbis capsid protein on the basis of its electrophoretic mobility in sodium dodecyl sulfate-acrylamide gels and two-dimensional tryptic-peptide fingerprints. Various amounts of several additional discrete polypeptides are formed, depending on the components of the cell-free extracts. One of these polypeptides may be a prematurely terminated part of the viral-capsid protein, while another is larger in molecular weight than capsid protein but contains the capsid tryptic peptides. Several of the proteins formed in vitro also are detected in extracts of Sindbis-infected BHK cells labeled with [(35)S]methionine. The three proteins found in Sindbis virions are postulated to originate by proteolytic cleavage from a larger molecular weight polypeptide precursor that is translated from a polycistronic mRNA presumed to contain a single site for initiation of protein synthesis. The two in vitro systems appear to translate this polycistronic viral mRNA to yield specific viral capsid although no evidence was found for post-translational proteolysis. Other mechanisms for production of the capsid protein in the cell-free extracts are considered, and some of these may function in the viral-infected cell where unusually large amounts of viral capsid proteins are frequently detected.
