Defective interfering Semliki Forest virus populations are biologically and physically heterogeneous

Alan Barrett, C. F. Crouch, N. J. Dimmock

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

This study demonstrates that populations of defective interfering Semliki Forest virus (DI SFV) are heterogeneous particularly in respect of their interference properties. Interference was quantified by two assays, one measuring inhibition of the yield of infectious progeny virus, and the other measuring reduction in virus-directed RNA synthesis; for 11 different DI SFV preparations a ratio of the two interference titres was calculated. These ratios varied up to 46-fold indicating that each DI virus preparation contained an interference activity that varied independently of the other. However, sister stocks made from the same parental inoculum had similar properties. The effects of different DI virus preparations on other parameters (virus polypeptide synthesis, yield of DI virus and yield of infectious virus) were investigated using inocula with interference titres standardized by either assay. Co-inoculation of L929 cells with 50 p.f.u. SFV showed that these parameters varied independently of each other and of the DI virus inoculum. There was no correlation with the number of undiluted passages each DI stock had received. Direct evidence of physical heterogeneity was demonstrated by metrizamide density gradient centrifugation. Although infecting virus sedimented as a narrow band, DI SFV was distributed over a broad region of the gradient. Its position on the gradient indicated that DI SFV has a higher nucleic acid:protein ratio than standard virus. DI virus progeny obtained by using fractions of the gradient as inoculum were as heterogeneous as the unfractionated parent, confirming that DI viruses retain heterogeneity on passage.

Original languageEnglish (US)
Pages (from-to)1273-1283
Number of pages11
JournalJournal of General Virology
Volume65
Issue number8
StatePublished - 1984
Externally publishedYes

Fingerprint

Semliki forest virus
Viruses
Population
Metrizamide
Density Gradient Centrifugation
RNA Viruses
Nucleic Acids

ASJC Scopus subject areas

  • Immunology
  • Virology

Cite this

Defective interfering Semliki Forest virus populations are biologically and physically heterogeneous. / Barrett, Alan; Crouch, C. F.; Dimmock, N. J.

In: Journal of General Virology, Vol. 65, No. 8, 1984, p. 1273-1283.

Research output: Contribution to journalArticle

@article{0e8f7b54f0e444d48cb58a5f889d8059,
title = "Defective interfering Semliki Forest virus populations are biologically and physically heterogeneous",
abstract = "This study demonstrates that populations of defective interfering Semliki Forest virus (DI SFV) are heterogeneous particularly in respect of their interference properties. Interference was quantified by two assays, one measuring inhibition of the yield of infectious progeny virus, and the other measuring reduction in virus-directed RNA synthesis; for 11 different DI SFV preparations a ratio of the two interference titres was calculated. These ratios varied up to 46-fold indicating that each DI virus preparation contained an interference activity that varied independently of the other. However, sister stocks made from the same parental inoculum had similar properties. The effects of different DI virus preparations on other parameters (virus polypeptide synthesis, yield of DI virus and yield of infectious virus) were investigated using inocula with interference titres standardized by either assay. Co-inoculation of L929 cells with 50 p.f.u. SFV showed that these parameters varied independently of each other and of the DI virus inoculum. There was no correlation with the number of undiluted passages each DI stock had received. Direct evidence of physical heterogeneity was demonstrated by metrizamide density gradient centrifugation. Although infecting virus sedimented as a narrow band, DI SFV was distributed over a broad region of the gradient. Its position on the gradient indicated that DI SFV has a higher nucleic acid:protein ratio than standard virus. DI virus progeny obtained by using fractions of the gradient as inoculum were as heterogeneous as the unfractionated parent, confirming that DI viruses retain heterogeneity on passage.",
author = "Alan Barrett and Crouch, {C. F.} and Dimmock, {N. J.}",
year = "1984",
language = "English (US)",
volume = "65",
pages = "1273--1283",
journal = "Journal of General Virology",
issn = "0022-1317",
publisher = "Society for General Microbiology",
number = "8",

}

TY - JOUR

T1 - Defective interfering Semliki Forest virus populations are biologically and physically heterogeneous

AU - Barrett, Alan

AU - Crouch, C. F.

AU - Dimmock, N. J.

PY - 1984

Y1 - 1984

N2 - This study demonstrates that populations of defective interfering Semliki Forest virus (DI SFV) are heterogeneous particularly in respect of their interference properties. Interference was quantified by two assays, one measuring inhibition of the yield of infectious progeny virus, and the other measuring reduction in virus-directed RNA synthesis; for 11 different DI SFV preparations a ratio of the two interference titres was calculated. These ratios varied up to 46-fold indicating that each DI virus preparation contained an interference activity that varied independently of the other. However, sister stocks made from the same parental inoculum had similar properties. The effects of different DI virus preparations on other parameters (virus polypeptide synthesis, yield of DI virus and yield of infectious virus) were investigated using inocula with interference titres standardized by either assay. Co-inoculation of L929 cells with 50 p.f.u. SFV showed that these parameters varied independently of each other and of the DI virus inoculum. There was no correlation with the number of undiluted passages each DI stock had received. Direct evidence of physical heterogeneity was demonstrated by metrizamide density gradient centrifugation. Although infecting virus sedimented as a narrow band, DI SFV was distributed over a broad region of the gradient. Its position on the gradient indicated that DI SFV has a higher nucleic acid:protein ratio than standard virus. DI virus progeny obtained by using fractions of the gradient as inoculum were as heterogeneous as the unfractionated parent, confirming that DI viruses retain heterogeneity on passage.

AB - This study demonstrates that populations of defective interfering Semliki Forest virus (DI SFV) are heterogeneous particularly in respect of their interference properties. Interference was quantified by two assays, one measuring inhibition of the yield of infectious progeny virus, and the other measuring reduction in virus-directed RNA synthesis; for 11 different DI SFV preparations a ratio of the two interference titres was calculated. These ratios varied up to 46-fold indicating that each DI virus preparation contained an interference activity that varied independently of the other. However, sister stocks made from the same parental inoculum had similar properties. The effects of different DI virus preparations on other parameters (virus polypeptide synthesis, yield of DI virus and yield of infectious virus) were investigated using inocula with interference titres standardized by either assay. Co-inoculation of L929 cells with 50 p.f.u. SFV showed that these parameters varied independently of each other and of the DI virus inoculum. There was no correlation with the number of undiluted passages each DI stock had received. Direct evidence of physical heterogeneity was demonstrated by metrizamide density gradient centrifugation. Although infecting virus sedimented as a narrow band, DI SFV was distributed over a broad region of the gradient. Its position on the gradient indicated that DI SFV has a higher nucleic acid:protein ratio than standard virus. DI virus progeny obtained by using fractions of the gradient as inoculum were as heterogeneous as the unfractionated parent, confirming that DI viruses retain heterogeneity on passage.

UR - http://www.scopus.com/inward/record.url?scp=0021261864&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021261864&partnerID=8YFLogxK

M3 - Article

C2 - 6747604

AN - SCOPUS:0021261864

VL - 65

SP - 1273

EP - 1283

JO - Journal of General Virology

JF - Journal of General Virology

SN - 0022-1317

IS - 8

ER -