A Novel Flavonoid Biosynthesis Gene Cluster Involved in Regulating High-Altitude Adaptability in Fagopyrum

Recently, the Team for Exploration and Innovative Utilization of Superior Germplasm Resources of Characteristic Crops at the Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (ICS-CAAS), identified a novel flavonoid biosynthetic gene cluster, UFGT3, in Fagopyrum. They also elucidated the mechanism by which this gene cluster regulates adaptation to high-altitude environments. This research provides a foundation for exploring the relationship between flavonoids and the environmental adaptability of buckwheat. The related findings have been published in the journal Advanced Science.

China is recognized as the center of origin and diversity for buckwheat. Buckwheat is distinguished by its short growth cycle, exceptional environmental adaptability, and high levels of bioactive flavonoids, particularly rutin. Extensive research indicates that the content of flavonoids is not only an important quality trait of buckwheat but is also closely related to its strong environmental adaptability. Therefore, identifying key genes that regulate the biosynthesis of flavonoids and elucidating their molecular regulatory pathways is crucial for future molecular breeding and the development of breakthrough buckwheat varieties.

Based on buckwheat germplasm resources from around the world, the research team conducted a whole-genome association analysis and discovered that a specific nucleotide variation in the promoter region of a glucosyltransferase gene in Tartary buckwheat is closely associated with the content of various flavonoids. Further analysis of genes neighboring this locus led to the identification of a unique biosynthesis gene cluster, UFGT3. This cluster includes a kinase gene (PAK), two transcription factor genes (MADS1/2), and a glucosyltransferase gene (UFGT3). These four components interact to form a molecular module that regulates flavonoid biosynthesis. Further studies revealed that in wild relatives, the anthocyanin glucosyltransferase gene (AGT) is regulated by this molecular module, catalyzing the production of flavonoids that protect plants from UV damage, thus enhancing high-altitude adaptability. Additionally, the study found that the UFGT3 gene cluster is widely present in buckwheat species and maintains structural and functional conservation in cultivated buckwheat. This research offers new insights into the molecular mechanisms underlying flavonoid biosynthesis and plant ecological adaptation in buckwheat.

The Regulatory Mechanism of the UFGT3 Gene Cluster Mediating Differences in High-Altitude Adaptability Between Wild and Cultivated Buckwheat 

Dr. Huang Xu, Associate Researchers He Yuqi and Zhang Kaixuan are the co-first authors of the paper, with Researcher Zhou Meiliang serving as the corresponding author. Academician Liu Xu of the Chinese Academy of Engineering provided guidance for this research. Collaborators from Chungbuk National University, Université Catholique de Louvain, the Bulgarian Academy of Sciences, and the Max Planck Institute of Molecular Plant Physiology provided local buckwheat genetic resources.

The study was supported by the National Key R&D Program of China, the Chinese Academy of Agricultural Sciences' Youth Innovation Project, and the European Union's Horizon 2020 program.

Original link: https://onlinelibrary.wiley.com/doi/10.1002/advs.202403603