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Sobemoviruses possess a common CfMV-like genomic organization
1Department of Gene Technology, Tallinn University of Technology, Tallinn, Estonia. merike.meier@ttu.ee
Archives of Virology
|November 23, 2006
Summary
Sobemoviruses were previously classified into two types based on genome structure. This study reveals these sobemoviruses share a common genome organization, challenging existing classifications.
Area of Science:
- Plant Virology
- Molecular Biology
- Genomics
Background:
- Sobemoviruses exhibit distinct genome organizations, primarily differing in the ORF2 region, leading to classifications like southern cowpea mosaic virus (SCPMV)-like and cocksfoot mottle virus (CfMV)-like.
- Despite structural differences, ORF2 encodes nearly identical amino acid sequences in different reading frames, suggesting potential for conserved genomic organization.
Purpose of the Study:
- To re-examine the genomic organization of four SCPMV-like sobemoviruses.
- To determine if nucleotide sequence variations account for the observed differences in genome structure.
- To reassess the classification of these sobemoviruses based on molecular evidence.
Main Methods:
- Resequencing of specific inconsistency regions within the ORF2 of four SCPMV-like sobemovirus isolates: lucerne transient streak virus, ryegrass mottle virus, southern bean mosaic virus, and SCPMV.
- Comparative analysis of the newly obtained nucleic acid sequences with previously published data.
- Bioinformatic analysis to compare nucleotide composition and infer genomic organization.
Main Results:
- Crucial differences in nucleic acid composition were identified in the resequenced regions.
- These differences indicate that the analyzed SCPMV-like sobemoviruses actually possess a CfMV-like genomic organization.
- The findings suggest that simple nucleotide insertions or deletions could explain the previously perceived structural variations.
Conclusions:
- The structural differences in ORF2 previously used for sobemovirus classification are likely due to nucleotide variations rather than fundamental differences in genome organization.
- Four SCPMV-like sobemoviruses (lucerne transient streak virus, ryegrass mottle virus, southern bean mosaic virus, and SCPMV) exhibit a common CfMV-like genomic organization.
- This study necessitates a revision of sobemovirus classification based on molecular data, highlighting conserved genomic features.
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