Plant viruses cause extensive remodeling of infected cells. These structural alterations include reshaping organelles, proliferation of membranes and membranous vesicles and modification of the plasmodesmata. Virus-induced sub-cellular structures, often containing host membranes, function for the production of progeny viral genome and/or for intra- and inter-cellular trafficking of viral genome-protein complexes, whose movement ultimately leads to the infection of the whole plant. In addition, host defense responses are associated with the formation of discrete sub-cellular structures (e.g. RNA processing bodies or stress granules) thought to be the site of translational repression.
In 2013, we launched in Frontiers in Plant Science Research Topic on Plant Virus Infection – a Cell Biology Perspective. Its aim was to provide the latest information on the molecular and cellular requirements that underlie the biogenesis of virus-induced structures and their function. Thirteen research and review articles presented key findings and syntheses enhancing our understanding of this topic. For example, how viral proteins induce membrane proliferation and alter membrane structure (e.g., curvature) as well as the roles of particular movement proteins in viral RNA replication, virus cell-to-cell and systemic spread and RNA silencing suppression. Additional subjects included a) the complex involvement of the cytoskeleton in virus movement and b) recruitment of host proteins, such as chaperones, and involvement of the unfolded protein response during virus infections.
As much has occurred since that Research Topic, we believe that it is the right time for an update on this topic. For example, more refined information on the architecture of viral factories and other subcellular structures (e.g. identification of host and lipid components) has been published. Determinants within viral proteins needed for membrane alterations have been characterized. Mechanisms for viral complex intracellular trafficking are better understood, as well as the viral entity(ies) involved in cell-to-cell or systemic movement. However, there are still many questions that have not been answered. Although the composition and cellular location of viral factories may vary greatly depending on the virus, the transition between these initially formed structures and the passage of the viral nucleic acid-protein complex through plasmodesmata is not well characterized. Furthermore, the nature of the viral nucleic acid-protein complexes observed in the phloem during systemic infection is not known, and the roles of RNA processing bodies and the cellular localization of RNA silencing components are not well understood.
It is with these issues in mind that we encourage individuals to contribute their expertise for an update of this Research Topic. All types of contributions are welcome. We cordially invite Original Research Articles and “State-of-the-Art” reviews on the diverse aspects of the topic, for instance on what plant viruses do to the host cell interior and how they do it. Comparisons of findings with those from studies on other plant pathogens or animal viruses are encouraged. We applaud commentaries on important questions that remain unaddressed and how they can be answered. Technology is also an important component for these investigations and we welcome “Technical Advances” articles describing tools for studying viruses from a cell biology perspective.
Plant viruses cause extensive remodeling of infected cells. These structural alterations include reshaping organelles, proliferation of membranes and membranous vesicles and modification of the plasmodesmata. Virus-induced sub-cellular structures, often containing host membranes, function for the production of progeny viral genome and/or for intra- and inter-cellular trafficking of viral genome-protein complexes, whose movement ultimately leads to the infection of the whole plant. In addition, host defense responses are associated with the formation of discrete sub-cellular structures (e.g. RNA processing bodies or stress granules) thought to be the site of translational repression.
In 2013, we launched in Frontiers in Plant Science Research Topic on Plant Virus Infection – a Cell Biology Perspective. Its aim was to provide the latest information on the molecular and cellular requirements that underlie the biogenesis of virus-induced structures and their function. Thirteen research and review articles presented key findings and syntheses enhancing our understanding of this topic. For example, how viral proteins induce membrane proliferation and alter membrane structure (e.g., curvature) as well as the roles of particular movement proteins in viral RNA replication, virus cell-to-cell and systemic spread and RNA silencing suppression. Additional subjects included a) the complex involvement of the cytoskeleton in virus movement and b) recruitment of host proteins, such as chaperones, and involvement of the unfolded protein response during virus infections.
As much has occurred since that Research Topic, we believe that it is the right time for an update on this topic. For example, more refined information on the architecture of viral factories and other subcellular structures (e.g. identification of host and lipid components) has been published. Determinants within viral proteins needed for membrane alterations have been characterized. Mechanisms for viral complex intracellular trafficking are better understood, as well as the viral entity(ies) involved in cell-to-cell or systemic movement. However, there are still many questions that have not been answered. Although the composition and cellular location of viral factories may vary greatly depending on the virus, the transition between these initially formed structures and the passage of the viral nucleic acid-protein complex through plasmodesmata is not well characterized. Furthermore, the nature of the viral nucleic acid-protein complexes observed in the phloem during systemic infection is not known, and the roles of RNA processing bodies and the cellular localization of RNA silencing components are not well understood.
It is with these issues in mind that we encourage individuals to contribute their expertise for an update of this Research Topic. All types of contributions are welcome. We cordially invite Original Research Articles and “State-of-the-Art” reviews on the diverse aspects of the topic, for instance on what plant viruses do to the host cell interior and how they do it. Comparisons of findings with those from studies on other plant pathogens or animal viruses are encouraged. We applaud commentaries on important questions that remain unaddressed and how they can be answered. Technology is also an important component for these investigations and we welcome “Technical Advances” articles describing tools for studying viruses from a cell biology perspective.
