文献类型： 外文期刊

作者： Gao, Xiao-ru ¹ ; Zhang, Huan ¹ ; Li, Xu ¹ ; Bai, Yi-wei ¹ ; Peng, Kui ¹ ; Wang, Zhen ¹ ; Dai, Zhuo-ru ¹ ; Bian, Xiao-feng ¹ ; Zhang, Qian ¹ ; Jia, Li-cong ¹ ; Li, Yan ¹ ; Liu, Qing-chang ¹ ; Zhai, Hong ¹ ; Gao, Shao-pei ¹ ; Zhao, Ning ¹ ; He, Shao-zhen ¹ ;

作者机构： 1.China Agr Univ, Key Lab Sweet Potato Biol & Biotechnol, Beijing Key Lab Crop Genet Improvement, Coll Agron & Biotechnol,Minist Agr & Rural Affairs, Beijing 100193, Peoples R China

2.China Agr Univ, Sanya Inst, Hainan 572025, Peoples R China

3.Jiangsu Acad Agr Sci, Inst Food Crops, Prov Key Lab Agrobiol, Nanjing 210000, Peoples R China

4.Yantai Acad Agr Sci, Inst Grain & Oil Crops, Yantai 265500, Peoples R China

5.Southwest Univ, Coll Agron & Biotechnol, Chongqing 400715, Peoples R China

期刊名称：PLANT PHYSIOLOGY （ 影响因子：8.005； 五年影响因子：9.115 ）

ISSN： 0032-0889

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收录情况： SCI

摘要： A B-box (BBX) family transcription factor regulates auxin-mediated leaf development and flavonoid accumulation in sweet potato by targeting specific genes and via protein-protein interactions. Plant flavonoids are valuable natural antioxidants. Sweet potato (Ipomoea batatas) leaves are rich in flavonoids, regenerate rapidly, and can adapt to harsh environments, making them an ideal material for flavonoid biofortification. Here, we demonstrate that the B-box (BBX) family transcription factor IbBBX29 regulates the flavonoid contents and development of sweet potato leaves. IbBBX29 was highly expressed in sweet potato leaves and significantly induced by auxin (IAA). Overexpression of IbBBX29 contributed to a 21.37%-70.94% increase in leaf biomass, a 12.08%-21.85% increase in IAA levels, and a 31.33%-63.03% increase in flavonoid accumulation in sweet potato, whereas silencing this gene produced opposite effects. Heterologous expression of IbBBX29 in Arabidopsis (Arabidopsis thaliana) led to a dwarfed phenotype, along with enhanced IAA and flavonoid accumulation. RNA-seq analysis revealed that IbBBX29 modulates the expression of genes involved in the IAA signaling and flavonoid biosynthesis pathways. Chromatin immunoprecipitation-quantitative polymerase chain reaction and electrophoretic mobility shift assay indicated that IbBBX29 targets key genes of IAA signaling and flavonoid biosynthesis to activate their expression by binding to specific T/G-boxes in their promoters, especially those adjacent to the transcription start site. Moreover, IbBBX29 physically interacted with developmental and phenylpropanoid biosynthesis-related proteins, such as AGAMOUS-LIKE 21 protein IbAGL21 and MYB308-like protein IbMYB308L. Finally, overexpressing IbBBX29 also increased flavonoid contents in sweet potato storage roots. These findings indicate that IbBBX29 plays a pivotal role in regulating IAA-mediated leaf development and flavonoid biosynthesis in sweet potato and Arabidopsis, providing a candidate gene for flavonoid biofortification in plants.