Complex dynamics of defective interfering baculoviruses during serial passage in insect cells

M.P. Zwart, G.P. Pijlman, J. Sardanyes, J. Duarte, C. Januario, S.F. Elena

Research output: Contribution to journalArticleAcademicpeer-review

9 Citations (Scopus)

Abstract

Defective interfering (DI) viruses are thought to cause oscillations in virus levels, known as the ‘Von Magnus effect’. Interference by DI viruses has been proposed to underlie these dynamics, although experimental tests of this idea have not been forthcoming. For the baculoviruses, insect viruses commonly used for the expression of heterologous proteins in insect cells, the molecular mechanisms underlying DI generation have been investigated. However, the dynamics of baculovirus populations harboring DIs have not been studied in detail. In order to address this issue, we used quantitative real-time PCR to determine the levels of helper and DI viruses during 50 serial passages of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) in Sf21 cells. Unexpectedly, the helper and DI viruses changed levels largely in phase, and oscillations were highly irregular, suggesting the presence of chaos. We therefore developed a simple mathematical model of baculovirus-DI dynamics. This theoretical model reproduced patterns qualitatively similar to the experimental data. Although we cannot exclude that experimental variation (noise) plays an important role in generating the observed patterns, the presence of chaos in the model dynamics was confirmed with the computation of the maximal Lyapunov exponent, and a Ruelle-Takens-Newhouse route to chaos was identified at decreasing production of DI viruses, using mutation as a control parameter. Our results contribute to a better understanding of the dynamics of DI baculoviruses, and suggest that changes in virus levels over passages may exhibit chaos
Original languageEnglish
Pages (from-to)327-342
JournalJournal of Biological Physics
Volume39
Issue number2
DOIs
Publication statusPublished - 2013

Keywords

  • nuclear polyhedrosis-virus
  • non-hr origin
  • dna-replication
  • double scroll
  • particles
  • infection
  • chaos
  • protein
  • fluctuations
  • multiplicity

Fingerprint Dive into the research topics of 'Complex dynamics of defective interfering baculoviruses during serial passage in insect cells'. Together they form a unique fingerprint.

Cite this