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Updated: Aug 9, 2026
11:28
Dissecting Host-virus Interaction in Lytic Replication of a Model Herpesvirus
Published on: October 7, 2011
Bipartite geminivirus host adaptation determined cooperatively by coding and noncoding sequences of the genome
I T Petty1, S C Carter, M R Morra
1Department of Microbiology, North Carolina State University, Raleigh, North Carolina 27695-7615, USA. tim_petty@ncsu.edu
Virology
|November 18, 2000
Summary
Researchers engineered hybrid bipartite geminiviruses (plant viruses) to study host adaptation. Combining all exchangeable genes and noncoding regions from tomato golden mosaic virus (TGMV) into bean golden mosaic virus (BGMV) fully transferred TGMV
Area of Science:
- Plant virology
- Molecular biology
- Genetics
Background:
- Bipartite geminiviruses are single-stranded DNA viruses that infect plants.
- These viruses exhibit host-specific adaptation despite genetic relatedness.
- Bean golden mosaic virus (BGMV) and tomato golden mosaic virus (TGMV) show distinct host preferences.
Purpose of the Study:
- To investigate the genetic determinants of host-specific adaptation in bipartite geminiviruses.
- To analyze the roles of open reading frames (ORFs) and noncoding regions (NCRs) in viral host adaptation.
- To construct and characterize hybrid viruses with exchanged genetic elements between BGMV and TGMV.
Main Methods:
- Construction of BGMV-TGMV hybrid viruses with specific genetic element exchanges (ORFs, NCRs).
- Analysis of hybrid virus infectivity and phenotype in different plant hosts (e.g., Nicotiana benthamiana, Phaseolus vulgaris).
- Evaluation of the contribution of individual genetic components to host-adapted traits.
Main Results:
- Hybrid viruses with exchanged ORFs (excluding AL1) showed partial host adaptation transfer.
- Exchange of NCRs alone did not confer host-specific adaptation.
- A BGMV-based hybrid with combined TGMV ORFs and NCRs achieved complete TGMV-like adaptation in N. benthamiana.
- The reciprocal TGMV-based hybrid showed only partial adaptation in bean, suggesting complex interactions.
Conclusions:
- Both ORFs and NCRs contribute to the host-specific adaptation of bipartite geminiviruses.
- Complete host adaptation can be achieved by combining multiple genetic elements.
- Interactions between viral components and host factors are crucial for viral adaptation and may involve sequence-specific interactions.
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