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Alphaflexiviridae in Focus: Genomic Signatures, Conserved Elements and Viral-Driven Cellular Remodeling
Jesús R Úbeda1, Miguel A Aranda1, Livia Donaire1
1Centro de Edafología y Biología Aplicada del Segura (CEBAS)-CSIC, Department of Stress Biology and Plant Pathology, P.O. Box 164, Espinardo, 30100 Murcia, Spain.
Viruses
|May 28, 2025
Summary
Alphaflexiviridae viruses infect plants and fungi, featuring filamentous RNA genomes. This review details their genomic structure, phylogeny, and the role of triple gene block proteins in virus movement and host interactions.
Area of Science:
- Virology
- Plant Pathology
- Fungal Virology
Background:
- The family Alphaflexiviridae encompasses plant- and fungus-infecting viruses with single-stranded, positive-sense RNA genomes.
- Virions are flexuous and filamentous, with 72 species classified into six genera, including the large genus Potexvirus.
- Potexvirus ecspotati (potato virus X) is a significant crop pathogen and a model organism in plant virology.
Purpose of the Study:
- To review current knowledge on the genomic structure, conserved genes, and phylogenetic relationships within Alphaflexiviridae.
- To focus on replicase and coat protein genes as key markers for species differentiation.
- To update the understanding of cellular remodeling mediated by triple gene block proteins essential for virus functions.
Main Methods:
- Review and synthesis of existing literature on Alphaflexiviridae.
- Analysis of genomic structure, conserved genes, and phylogenetic data.
- Focus on sequence identity thresholds for species classification.
Main Results:
- Detailed summary of genomic organization and conserved genes across Alphaflexiviridae genera.
- Identification of replicase and coat protein genes as crucial for phylogenetic analysis and species demarcation.
- Updated model of cellular remodeling by triple gene block proteins, highlighting their role in virus movement.
Conclusions:
- Alphaflexiviridae viruses exhibit diverse host ranges and genomic features, with clear phylogenetic distinctions.
- Triple gene block proteins play a critical role in virus replication, movement, and host interaction.
- Alphaflexiviruses are valuable models for virus-host dynamics, with potential applications in crop protection and biotechnology.
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