Abstract
Flaviviruses are enveloped viruses which accumulate in cellular vacuoles prior to release. The membrane of cell-associated virus contains the proteins pre-M and E. During release of virus the pre-M protein is cleaved, and only its carboxy-terminal segment remains associated with the virus as M protein. Studies of the association of membrane proteins of intracellular and extracellular particles of West Nile virus show that in cell-associated virus the pre-M and E proteins are present as E+pre-M heterodimers. Cleavage of pre-M during release leads to dissociation of the heterodimers: the amino-terminal region of the pre-M protein is lost from the virus, whereas the proteins M and E remain associated with the viral membrane as separate molecules. The E protein of extracellular virus has a tendency to oligomerize into trimers, and both E-protein monomers and trimers are present on extracellular virions. We have prepared partially purified extracellular virus without loss of viral infectivity. These preparations contain approximately 600 physical particles for each PFU. Since purification of cell-associated virus results in significant loss of PFU, an inactivation of virus may occur during this procedure. Preparations of cell-associated virus contained approximately 40,000 physical particles for each PFU.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Castle E., Nowak T., Leidner U., Wengler G., Wengler G. Sequence analysis of the viral core protein and the membrane-associated proteins V1 and NV2 of the flavivirus West Nile virus and of the genome sequence for these proteins. Virology. 1985 Sep;145(2):227–236. doi: 10.1016/0042-6822(85)90156-4. [DOI] [PubMed] [Google Scholar]
- Heinz F. X., Kunz C. Chemical crosslinking of tick-borne encephalitis virus and its subunits. J Gen Virol. 1980 Feb;46(2):301–309. doi: 10.1099/0022-1317-46-2-301. [DOI] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Nowak T., Wengler G. Analysis of disulfides present in the membrane proteins of the West Nile flavivirus. Virology. 1987 Jan;156(1):127–137. doi: 10.1016/0042-6822(87)90443-0. [DOI] [PubMed] [Google Scholar]
- Obijeski J. F., Marchenko A. T., Bishop D. H., Cann B. W., Murphy F. A. Comparative electrophoretic analysis of the virus proteins of four rhabdoviruses. J Gen Virol. 1974 Jan;22(1):21–33. doi: 10.1099/0022-1317-22-1-21. [DOI] [PubMed] [Google Scholar]
- Shapiro D., Brandt W. E., Russell P. K. Change involving a viral membrane glycoprotein during morphogenesis of group B arboviruses. Virology. 1972 Dec;50(3):906–911. doi: 10.1016/0042-6822(72)90445-x. [DOI] [PubMed] [Google Scholar]
- Staros J. V. N-hydroxysulfosuccinimide active esters: bis(N-hydroxysulfosuccinimide) esters of two dicarboxylic acids are hydrophilic, membrane-impermeant, protein cross-linkers. Biochemistry. 1982 Aug 17;21(17):3950–3955. doi: 10.1021/bi00260a008. [DOI] [PubMed] [Google Scholar]
- Wengler G., Beato M., Wengler G. In vitro translation of 42 S virus-specific RNA from cells infected with the flavivirus West Nile virus. Virology. 1979 Jul 30;96(2):516–529. doi: 10.1016/0042-6822(79)90108-9. [DOI] [PubMed] [Google Scholar]
- Wengler G., Castle E., Leidner U., Nowak T., Wengler G. Sequence analysis of the membrane protein V3 of the flavivirus West Nile virus and of its gene. Virology. 1985 Dec;147(2):264–274. doi: 10.1016/0042-6822(85)90129-1. [DOI] [PubMed] [Google Scholar]
- Wengler G., Wengler G., Nowak T., Wahn K. Analysis of the influence of proteolytic cleavage on the structural organization of the surface of the West Nile flavivirus leads to the isolation of a protease-resistant E protein oligomer from the viral surface. Virology. 1987 Sep;160(1):210–219. doi: 10.1016/0042-6822(87)90062-6. [DOI] [PubMed] [Google Scholar]
- Westaway E. G., Brinton M. A., Gaidamovich SYa, Horzinek M. C., Igarashi A., Käriäinen L., Lvov D. K., Porterfield J. S., Russell P. K., Trent D. W. Flaviviridae. Intervirology. 1985;24(4):183–192. doi: 10.1159/000149642. [DOI] [PubMed] [Google Scholar]
- Westaway E. G. Flavivirus replication strategy. Adv Virus Res. 1987;33:45–90. doi: 10.1016/s0065-3527(08)60316-4. [DOI] [PubMed] [Google Scholar]