Leveraging plant virus-vector molecular interactions for innovative vector and disease control.

Plant Viruses as Master Manipulators: Exploiting Host Plants and Insect Vectors for Enhanced Transmission.

Plant viruses are evolutionarily endowed with traits that enhance their survival and dissemination attributes both in host plants and insect vectors. This review highlights current understanding of these multifaceted interactions, positioning plant viruses as master regulators of the intricate tripartite interactions. Direct viral effects on vector physiology and behaviour, highlighting evidence that viral infection may contribute to changes in olfactory systems, epigenetic modifications, involvement of salivary effectors, and horizontal gene transfer events that may vary vector competence, were summarised. The indirect mechanisms mediated through virus-induced alterations in host plant responses, including changes in volatile emissions, the development of visually and chemically attractive symptoms, and modulation of host immune defences that may influence vector attraction and feeding behaviour, were discussed. These viral infections have profound ecological and agricultural consequences, reflecting the fine balance these pathogens maintain between preserving host viability and maximising transmission. In intensively managed agro-ecosystems, environmental and biological conditions can strengthen these interactions, potentially promoting epidemic spread and altering vector behaviour. Deciphering these evolutionary strategies deepens our understanding of the dynamics governing pathogen-host-vector systems and opens new possibilities for designing targeted, sustainable interventions to disrupt viral transmission in crops.

Virus-induced gene silencing as a tool for functional genomics in weeds: Challenges and future directions.

Virus-induced gene silencing (VIGS) has evolved from a conceptual demonstration of antiviral defense into a pivotal reverse-genetics platform for plant functional genomics. By exploiting engineered DNA- or RNA-based viral vectors, VIGS enables rapid, sequence-specific transcript knockdown through RNA-mediated degradation of target transcripts. Recent refinements in vector design, inoculation strategies, and viral species selection, such as TRV, BSMV, and FoMV, have expanded its application to previously recalcitrant plants, including major crops and emerging weed models. In weeds, functional genomics remains particularly challenging due to high genetic variability, limited genomic resources, and incompatibility with conventional viral vectors and transformation systems. In this context, VIGS provides a tractable approach to investigate genes associated with herbicide resistance, metabolic adaptation, and stress tolerance. Beyond weed biology, its application to studies of immune signaling, hormonal crosstalk, and secondary metabolism highlights VIGS as a versatile biotechnology for elucidating gene function and supporting next-generation strategies in plant improvement and integrated pest management.

Reduced risk of a next-generation recombinant viral vector engineered from a plant rhabdovirus genome

A Novel Approach to Engineering Tomato Spotted Wilt Virus Infectious Clones by Disarming Key Nodes in Anti-Viral Defenses.

Tomato spotted wilt virus (TSWV) is an economically devastating pathogen that rapidly overcomes genetic resistance in major crops. Reverse genetic systems are crucial for investigating plant-virus interactions and resistance breaking mechanisms, and developing these tools for segmented ambisense RNA viruses remains a crucial challenge. Current TSWV-clones rely on extensively modified Asian isolates requiring co-delivery of multiple replication helpers and viral silencing suppressors. Streamlining these systems for regionally significant strains with minimal genetic alterations is essential. Here we developed the first infectious clone of a USA TSWV isolate (PA01). Three binary plasmids contain cDNAs for the antigenomic L and S segments, and the genomic M segment, with enhanced GFP replacing NSs on the S segment. Co-delivery of the cucumovirus 2b alone or in combination with tombusvirus P19 or begomovirus AL2, achieved a high proportion of systemically infected Nicotiana benthamiana and Capsicum annuum plants. In N. tabacum, co-delivering the Caenorhabditis elegans cell death suppressor CED-9, or using NahG transgenic plants produced 20 to 62% systemically infected plants. These data indicate that in addition to the anti-viral RNA silencing machinery, additional host defense pathways influence TSWV rescue and systemic infection from cDNA.

Advances in the application of recombinant herpesvirus-vectored vaccines in animal disease control

Recombinant herpesvirus vectors have emerged as highly potent platforms for next-generation vaccine development, distinguished by their genomic capacity and their unique ability to elicit durable, long-lasting immunity through persistent latent infections. In this review, we trace the evolutionary trajectory of herpesvirus vector engineering—transitioning from traditional homologous recombination to advanced bacterial artificial chromosome (BAC) systems and precise, scarless CRISPR/Cas9 gene editing. We comprehensively evaluate the rational design of classical animal herpesvirus vectors, including pseudorabies virus (PRV), herpesvirus of turkeys (HVT), and feline herpesvirus type 1 (FHV-1). Specifically, we highlight their distinct advantages in molecular attenuation, the optimization of non-essential insertion loci, and the application of tissue-specific promoters for multiplexed antigen presentation. Furthermore, we discuss the strategic deployment of multivalent herpesvirus vaccines within the “One Health” framework, emphasizing their critical role in simplifying immunization protocols and interrupting the transmission chains of zoonotic diseases. Finally, we address the prevailing translational bottlenecks, including scalable manufacturing challenges and stringent regulatory frameworks regarding environmental release, providing perspectives on how continuous biotechnological innovations will empower herpesvirus vectors to serve as formidable prophylactic tools against emerging and re-emerging infectious diseases.

Molecular dialogues in plant rhabdovirus-host interactions.

Plant rhabdoviruses comprise a group of economically important pathogens that exhibit a complex dual-host infection cycle across plants and insect vectors, relying on exquisitely adapted cross-kingdom infection and survival strategies. In this review, we summarize recent advances in understanding plant rhabdovirus-host interactions, with a focus on the molecular basis underlying viral manipulation of host functions. We highlight key host factors or subcellular structures hijacked by plant rhabdoviruses to support robust viral replication and intracellular transport. We further explore the diverse counter-defense mechanisms deployed by plant rhabdoviruses to evade or suppress host immunity, including RNA silencing, phytohormone signaling cascades, and autophagy-mediated degradation. Finally, we discuss the intimate insect-virus interfaces, detailing how viral effectors modulate vector feeding behaviors, physiology, and innate immune responses to facilitate persistent, propagative transmission. Collectively, these advances establish an integrated framework for understanding the cross-kingdom pathogenesis of plant rhabdoviruses and provide insights for developing innovative crop protection strategies.