Infection with Strains of Citrus Tristeza Virus Does Not Exclude Superinfection by Other Strains of the Virus
- 1 February 2010
- journal article
- Published by American Society for Microbiology in Journal of Virology
- Vol. 84 (3), 1314-1325
- https://doi.org/10.1128/jvi.02075-09
Abstract
Superinfection exclusion or homologous interference, a phenomenon in which a primary viral infection prevents a secondary infection with the same or closely related virus, has been observed commonly for viruses in various systems, including viruses of bacteria, plants, and animals. With plant viruses, homologous interference initially was used as a test of virus relatedness to define whether two virus isolates were “strains” of the same virus or represented different viruses, and subsequently purposeful infection with a mild isolate was implemented as a protective measure against isolates of the virus causing severe disease. In this study we examined superinfection exclusion of Citrus tristeza virus (CTV), a positive-sense RNA closterovirus. Thirteen naturally occurring isolates of CTV representing five different virus strains and a set of isolates originated from virus constructs engineered based on an infectious cDNA clone of T36 isolate of CTV, including hybrids containing sequences from different isolates, were examined for their ability to prevent superinfection by another isolate of the virus. We show that superinfection exclusion occurred only between isolates of the same strain and not between isolates of different strains. When isolates of the same strain were used for sequential plant inoculation, the primary infection provided complete exclusion of the challenge isolate, whereas isolates from heterologous strains appeared to have no effect on replication, movement or systemic infection by the challenge virus. Surprisingly, substitution of extended cognate sequences from isolates of the T68 or T30 strains into T36 did not confer the ability of resulting hybrid viruses to exclude superinfection by those donor strains. Overall, these results do not appear to be explained by mechanisms proposed previously for other viruses. Moreover, these observations bring an understanding of some previously unexplained fundamental features of CTV biology and, most importantly, build a foundation for the strategy of selecting mild isolates that would efficiently exclude severe virus isolates as a practical means to control CTV diseases.Keywords
This publication has 87 references indexed in Scilit:
- Citrus Tristeza Virus : Survival at the Edge of the Movement ContinuumJournal of Virology, 2008
- Persistent Infection and Promiscuous Recombination of Multiple Genotypes of an RNA Virus within a Single Host Generate Extensive DiversityPLOS ONE, 2007
- Analysis of Hepatitis C Virus Superinfection Exclusion by Using Novel Fluorochrome Gene-Tagged Viral GenomesJournal of Virology, 2007
- Contribution of Vpu, Env, and Nef to CD4 Down-Modulation and Resistance of Human Immunodeficiency Virus Type 1-Infected T Cells to SuperinfectionJournal of Virology, 2006
- Comparative and functional genomics of closterovirusesVirus Research, 2006
- Assessment of sequence diversity in the 5′-terminal region of Citrus tristeza virus from IndiaVirus Research, 2005
- RNA silencing in plantsNature, 2004
- Citrus Tristeza Virus and Its Aphid VectorToxoptera citmicida: Threats to Citrus Production in the Caribbean and Central and North AmericaPlant Disease, 1995
- Evaluation of Citrus Tristeza Virus Isolates for Cross Protection of Grapefruit in South AfricaPlant Disease, 1993
- A Monoclonal Antibody That Discriminates Strains of Citrus Tristeza VirusPhytopathology®, 1990