HuLBD1 Promotes Flavonoid Biosynthesis Involved in Senescence of Hylocereus undatus by Negatively Regulating HuCHS  

作　　者：Xinxin Chen Fuxin Li Jingyu Jia Yajing Tian Xin Li 

机构地区：[1]College of Food and Bioengineering,Henan University of Science and Technology,Luoyang,471023,China [2]Henan Engineering Research Center of Food Microbiology,Luoyang,471023,China [3]The National and Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology of Characteristic Fruit Trees in South Xinjiang,Tarim University,Alar,843300,China

出　　处：《Phyton-International Journal of Experimental Botany》2025年第3期825-842,共18页国际实验植物学杂志(英文)

基　　金：supported by the National Key Research and Development Program of China(2017YFC1600802);Henan Provincial Science and Technology Research Project,China(No.232102110134);the National and Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology of Characteristic Fruit Trees in South Xinjiang of China(No.FE202303).

摘　　要：In plants, transcription factor (TF) family LATERAL ORGAN BOUNDARIES DOMAIN (LBD) has been identified to be involved in the ripening and senescence processes of fruits. However, the function of LBD in Hylocereus undatus (Haw.) Britton & Rose (H. undatus) has not been reported yet. Through transcriptomic analysis, virus-induced gene silencing (VIGS) technology, and RT-qPCR validation, we investigated the role of the LBD TFs in the senescence of H. undatus. Transcriptomic analysis revealed that HuLBD1 is a key transcription factor of the LBD family regulating H. undatus senescence. After silencing HuLBD1, 5075 differentially expressed genes (DEGs) were identified. GSEA results showed that these DEGs were mainly enriched in the phenylpropanoids and flavonoid biosynthesis pathway. The leading subset of genes in these two pathways included 16 DEGs, with four upregulated genes, HuCHS1-2, HuFLS1, HuCYP75B2, and HuCHS5-2 being central in the Protein-Protein Interaction (PPI) network. H. undatus phenotypic experiments confirmed that silencing HuLBD1 significantly increased the flavonoid content in the fruit peel, and RT-qPCR validation showed that the gene expression trends were consistent with the RNA-seq data. The study indicated that HuLBD1 likely delays the fruit senescence process by negatively regulating the expression of four key genes, including HuCHS1-2, thus promoting the synthesis of phenylpropanoids such as flavonoids. In conclusion, our findings suggest that the HuLBD1 TF plays an important role in the senescence of H. undatus fruit, providing a theoretical basis for postharvest senescence control.

关 键 词：HuLBD1 Hylocereus undatus flavonoid biosynthesis VIGS TRANSCRIPTOMICS 

分 类 号：Q94[生物学—植物学]