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Characterization of Temperature-sensitive (ts) Mutants of Coronavirus Infectious Bronchitis Virus (IBV)

  • Shuo Shen
  • Ding Xiang Liu
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 494)

Abstract

Coronavirus infectious bronchitis virus is a positive-stranded RNA virus, which synthesises a 3’-coterminal nested set of six subgenomic RNAs. Subgenomic RNA transcription and genome replication are directed by the viral replicase, which is expressed in the form of polyproteins 1a and la/b and subsequently processed into smaller nonstructural proteins by the virusencoded proteinases. Major structural proteins S (spike protein), E (envelope protein), M (membrane protein) and N (nucleoprotein) are translated from subgenomic RNAs 2, 3, 4 and 6 and involved in nucleocapsid and virion assembling (Lai & Cavanagh 1998). Previous studies demonstrated that mutations and deletions on the structural proteins conferred the Coronavirus mouse hepatitis virus ts phenotypes (Masters et al 1994 & Luytjes et al 1997). However, little is known about the mechanisms involved. In this study, ts mutants were generated by growing wild type virus at progressively lower temperatures from 35°C to 28°C on Vero cells. Two ts mutants were isolated from passages grown at 29°C (ts291602) and 28°C (ts282902). Sequence analysis reveals that mutations emerged in the S protein and an insertion occurred in the N protein. Biological and biochemical properties of ts mutants were characterised.

Keywords

Vero Cell Infectious Bronchitis Virus Wild Type Virus Spike Protein Viral Structural Protein 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • Shuo Shen
    • 1
  • Ding Xiang Liu
    • 1
  1. 1.Institute of Molecular Agrobiology, 1 Research LinkeNational University of SingaporeSingapore

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