PlantView Supports Plant Antiviral Immunity Research: Far-red light orchestrates antiviral defense in plants

New progress has been made in understanding how far-red light regulates antiviral immunity in plants.

Professor Yule Liu’ s team from the School of Life Sciences, Tsinghua University, in collaboration with Researcher Qian Gong’ s team from the College of Advanced Agricultural Sciences, Peking University, published their findings in “ Science Advances” (IF = 12.5, Q1 journal).

This study uncovers a novel molecular mechanism by which far-red light enhances plant antiviral defense and reveals the counter-defense strategies evolved by plant viruses, providing new insights into environmentally friendly crop disease management.

Light is a key environmental signal governing plant growth and development. Its spectral composition changes significantly at dawn and dusk, when far-red light (FR) becomes enriched. Notably, these periods also coincide with peak activity of insect vectors such as aphids and whiteflies, thereby increasing the risk of viral infection in plants. Although light signaling has long been known to regulate plant growth, development, and certain immune responses, and the far-red light receptor phytochrome A (phyA) has been implicated in immune regulation, whether and how far-red light influences plant antiviral defense has remained largely unknown. In addition, phloem-feeding insects transmit approximately 80% of plant viruses, causing substantial agricultural losses. The mechanisms by which plants coordinate defenses against both insect attack and viral infection in response to fluctuating light environments, as well as the potential counter-defense strategies employed by viruses, have remained poorly understood.

To address these questions, the researchers elucidated a complete molecular mechanism underlying far-red light–mediated antiviral defense and the corresponding viral counter-defense strategy. Far-red light, enriched at dawn and dusk, activates phytochrome A (phyA), which promotes the degradation of Phytochrome-Interacting Factor 1 (PIF1). This relieves the repression of the transcription factor RVE7, leading to the activation of EDS1 expression. Through the salicylic acid (SA) signaling pathway, this mechanism enhances plant resistance to viruses such as Cucumber mosaic virus (CMV) and Potato virus Y (PVY), while simultaneously increasing resistance to aphids, thereby establishing a dual defense system against both viruses and their insect vectors. The core components of this pathway—phyA, RVE7, and EDS1—are all indispensable for effective defense. In response, several plant viruses, including CMV, PVY, and Tobacco mosaic virus (TMV), have evolved a conserved countermeasure. Their encoded RNA-dependent RNA polymerases (RdRPs) competitively disrupt the interaction between phyA and the nuclear transport factor FHY1, thereby blocking phyA nuclear translocation, suppressing activation of downstream defense pathways, and weakening plant resistance. These findings not only reveal the molecular logic by which plants utilize light signals to combat insect-transmitted viruses but also provide an important theoretical foundation for the precise application of far-red LED supplemental lighting in greenhouse horticulture and the development of environmentally friendly crop protection technologies.

Experiments using Plantview

In this study, the researchers employed the PlantView Plant In Vivo Imaging System developed by Guangzhou Biolight Biotechnology to perform a series of luciferase reporter gene assays.

DOI: 10.1126/sciadv.adz7663