文献类型： 外文期刊

作者： Liu, Xinya ¹ ; Chen, Beibei ⁴ ; Luo, Ling ¹ ; Zhong, Qi ¹ ; Teo, Chee How ⁴ ; Huang, Shengjia ⁵ ;

作者机构： 1.Sichuan Acad Agr Sci, Hort Res Inst, Chengdu 610023, Peoples R China

2.Minist Agr & Rural Affairs, Key Lab Crop Ecophysiol & Farming Syst Southwest, Chengdu 611130, Peoples R China

3.Key Lab Germplasm Innovat & Utilizat Hort Crops Si, Chengdu 610066, Peoples R China

4.Univ Malaya, Ctr Res Biotechnol Agr, Kuala Lumpur 50603, Malaysia

5.Sichuan Acad Forestry, Inst Econ Forest Res, Chengdu 610081, Peoples R China

关键词： citrus; hairy roots; CitFNSII-1; flavonoid

期刊名称：PLANTS-BASEL （ 影响因子：4.1； 五年影响因子：4.5 ）

ISSN： 2223-7747

年卷期： 2025 年 14 卷 13 期

页码：

收录情况： SCI

摘要： Flavonoid synthases (FNSs) are key enzymes catalyzing the conversion of flavanones to flavonoids, yet their functions in citrus remain functionally uncharacterized. In this study, we identified three FNSII genes in the citrus genome. Phylogenetic analysis revealed that citrus FNSII genes share the closest evolutionary distance with apple FNSII genes. Chromosomal localization demonstrated that the three FNSII genes are distributed across two out of nine chromosomes. Gene structure analysis indicated that the majority of motifs within these three FNSII genes are highly conserved. We cloned a gene called CitFNSII-1 from citrus. Transient overexpression of CitFNSII-1 in citrus leaves significantly increased flavonoid content, while simultaneous virus-induced silencing of CitFNSII-1 led to synchronously and significantly reduced gene expression levels and flavonoid content in citrus seedlings. Through the Agrobacterium rhizogenes-mediated genetic transformation system, overexpression of CitFNSII-1 was found to markedly enhance flavonoid accumulation in hairy roots, whereas knockout of CitFNSII-1 resulted in a significant decrease in flavonoid content in hairy roots. Further experiments verified an interaction between CitFNSII-1 and the Chalcone isomerase-1 (CHI-1) protein. The results demonstrated that the flavonoid accumulation patterns of CHI-1 and CitFNSII-1 are highly similar. In conclusion, this study advances the understanding of the flavonoid biosynthesis pathway in citrus and provides a theoretical foundation for molecular breeding strategies in citrus.