The Structure and Replication of a Parainfluenza Virus
type: CreativeWork
description: The simian parainfluenza virus SV5 is a member of myxovirus subgroup II, which includes parainfluenza, mumps, and Newcastle disease viruses. These viruses are 120-500 mμ in diameter, and consist of an envelope covered with surface projections and an internal ribonucleoprotein component which is a single-stranded helix, 150-180 A in diameter, A high yield of infective SV5 is produced by primary cultures of rhesus monkey kidney (MK) cells, and the virus-cell interaction is moderate: infected cells divide normally, exhibit little cyctopathic effect, and cellular macromolecular synthesis is not inhibited. An electron microscopic study of SV5 replication in MK cells was undertaken. Virus adsorbs to the cell surface and is then taken into cells by phagocytosis. Virus-induced morphological changes appear only in the cytoplasm of infected cells. The helical nucleocapsid of the virus appears to form in the cytoplasmic matrix and align under regions of the cell membrane which acquire viral surface projections. Assembly and release of virus particles at the cell surface occur by a budding process involving incorporation into the viral envelope of a unit membrane, which is continuous with and morphologically identical to that of the host cell. Both spherical and filamentous virus particles are formed. Filaments frequently contain nucleocapsid in a regular spiral which extends throughout their length. SV5 causes minimal cytopathic changes in MK cells, and there appears to be a balance between the rate of synthesis of nucleocapsid and its continuous release within mature virus particles. Under certain conditions, a gradual accumulation of nucleocapsid is seen in the cytoplasm of infected cells. This observation suggested an approach to the isolation of SV5 nucleocapsid. Equilibrium sedimentation in cesium chloride gradients was used to purify nucleocapsid released from cells by osmotic shock. The length distribution of the released nucleocapsid shows a sharp peak with a mean of 1…
abstract: The simian parainfluenza virus SV5 is a member of myxovirus subgroup II, which includes parainfluenza, mumps, and Newcastle disease viruses. These viruses are 120-500 mμ in diameter, and consist of an envelope covered with surface projections and an internal ribonucleoprotein component which is a single-stranded helix, 150-180 A in diameter, A high yield of infective SV5 is produced by primary cultures of rhesus monkey kidney (MK) cells, and the virus-cell interaction is moderate: infected cells divide normally, exhibit little cyctopathic effect, and cellular macromolecular synthesis is not inhibited. An electron microscopic study of SV5 replication in MK cells was undertaken. Virus adsorbs to the cell surface and is then taken into cells by phagocytosis. Virus-induced morphological changes appear only in the cytoplasm of infected cells. The helical nucleocapsid of the virus appears to form in the cytoplasmic matrix and align under regions of the cell membrane which acquire viral surface projections. Assembly and release of virus particles at the cell surface occur by a budding process involving incorporation into the viral envelope of a unit membrane, which is continuous with and morphologically identical to that of the host cell. Both spherical and filamentous virus particles are formed. Filaments frequently contain nucleocapsid in a regular spiral which extends throughout their length. SV5 causes minimal cytopathic changes in MK cells, and there appears to be a balance between the rate of synthesis of nucleocapsid and its continuous release within mature virus particles. Under certain conditions, a gradual accumulation of nucleocapsid is seen in the cytoplasm of infected cells. This observation suggested an approach to the isolation of SV5 nucleocapsid. Equilibrium sedimentation in cesium chloride gradients was used to purify nucleocapsid released from cells by osmotic shock. The length distribution of the released nucleocapsid shows a sharp peak with a mean of 1…
author: Compans, Richard W
keywords: SV5 replication, myxovirus morphology, nucleocapsid isolation, ribonucleoprotein structure, virus budding, pneumonia virus of mice, Life Sciences
date published: 1968-01-01T08:00:00Z
date modified: 2026-07-24T04:11:21Z
provider: Rockefeller
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Rockefeller