Flower power: Lily's genetic arsenal against devastating fungus
image: Working model of LlWRKY33-LlHSFA4-LlCAT2 module under Botrytis cinerea attack. When lily is infected with B. cinerea, LlWRKY33 is rapidly induced and directly activate the expression of LlHSFA4 and LlCAT2 by binding to their promoters. Notably, LlHSFA4 could also directly bind to the HSE on the promoter of LlCAT2 and activate its expression. LlCAT2, a ROS scavenging enzyme, acts as a common target of LlWRKY33 and LlHSFA4 to prevent cell death caused by ROS accumulation to confer resistance to B. cinerea in lily.
Credit: Horticulture Research
A pivotal study has uncovered a genetic defense mechanism in lily plants against Botrytis cinerea, the fungus behind gray mold disease. Central to this defense is LlHSFA4, a transcription factor that, when activated, initiates a robust response against the pathogen. This discovery could transform strategies for protecting horticultural crops from severe fungal infections.
Gray mold, caused by Botrytis cinerea, is a significant threat to lily cultivation worldwide, thriving in high-humidity and moderate temperatures. The pathogen attacks by releasing toxins and enzymes that lead to cell death and nutrient depletion in plant tissues. Plants have evolved complex defense responses, including transcription factors that regulate immunity. Given these challenges, delving into plant immune mechanisms and genetic interactions is crucial for cultivating crops with enhanced pathogen resistance.
Led by the College of Horticulture at Nanjing Agricultural University, this research, published (DOI: 10.1093/hr/uhad254) in Horticulture Research on November 27, 2024, details how the LlWRKY33-LlHSFA4-LlCAT2 gene module strengthens lilies against B. cinerea infection. Results show that these transcription factors work in concert to limit cell death and control reactive oxygen species (ROS) accumulation, two crucial elements in plant immune response.
The study reveals LlHSFA4’s essential role in lily’s defense against B. cinerea. When exposed to the fungus, LlHSFA4 expression increases, enhancing the plant's ability to manage ROS and prevent cell death. LlWRKY33 supports this defense by directly activating both LlHSFA4 and LlCAT2, creating a synchronized genetic defense network. This regulatory module enables LlHSFA4 and LlCAT2 to efficiently manage ROS levels, protecting plant cells from damage and restricting infection spread. Silencing LlHSFA4 heightened lily’s susceptibility, while overexpressing it in Arabidopsis improved resistance, highlighting the LlWRKY33-LlHSFA4-LlCAT2 pathway as a promising target for disease-resistant breeding.
Dr. Nianjun Teng, lead researcher at Nanjing Agricultural University, notes, "Our findings on LlWRKY33-LlHSFA4-LlCAT2 interactions offer a compelling natural strategy to combat plant pathogens. By leveraging this transcriptional module, we could develop resistant crop varieties, addressing global agricultural challenges caused by fungal diseases. Such insights are key to advancing sustainable crop management."
This gene module provides a promising blueprint for breeding disease-resistant lilies and potentially other crops. Enhancing natural plant immune responses through transcription factors like LlWRKY33 and LlHSFA4 reduces chemical dependence, fostering sustainable agricultural practices. Future research could extend this approach across species, broadening crop protection options against diverse pathogens.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhad254
Funding information
This research was supported by the National Key R&D Program of China (2023YFD2300900), the Project for Crop Germplasm Resources Conservation of Jiangsu (2021-SJ-011), and the Modern Agricultural Industry Technology System in Jiangsu [JATS (2023) 007].
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.