Deng Yuan-Jie, Duan Ao-Qi, Li Tong, Tan Shan-Shan, Liu Shan-Shan, Wang Ya-Hui, Ma Jing, Li Jing-Wen, Liu Hui, Xu Zhi-Sheng, Liang Yi, Zhou Jian-Hua, Xiong Ai-Sheng
State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East China, College of Horticulture, Nanjing Agricultural University, Nanjing, China.
Beijing Vegetable Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.
Plant Cell Environ. 2025 May;48(5):3118-3135. doi: 10.1111/pce.15331. Epub 2024 Dec 18.
CYP97C1 as a haem-containing cytochrome P450 hydroxylase (P450-type) is important for carotene hydroxylation and xanthophyll biosynthesis. Research about this type of hydroxylase was mainly reported in several model plant species which have no specialized tissues accumulating massive carotenoids. The function of CYP97C1 in the horticultural plant, like carrots, was not fully studied. In this study, we focused on the role of DcCYP97C1 in carotenoid flux and colour formation in carrot. DcCYP97C1 was found highly expressed in the 'turning stage' of carrot taproot. Using stable transformation and CRISPR/Cas9-mediated gene knockout technology, DcCYP97C1 was confirmed the rate-limiting enzyme for lutein biosynthesis and important for taproot colour formation. Overexpression of DcCYP97C1 in an orange carrot KRD (Kurodagosun) resulted in five times overproduction of lutein accompanied by dramatic reduction of carotenes. Knockout of DcCYP97C1 in orange KRD and yellow carrot QTH (Qitouhuang) reduced all kinds of carotenoids including lutein, α-carotene and β-carotene reflecting the key role of DcCYP97C1 for total carotenoid accumulation in taproot 'turning stage'. Our study demonstrated that manipulation of DcCYP97C1 was sufficient to influence carotenoid flux, change carrot colour and for high lutein production. The uncovered role of DcCYP97C1 may be helpful for understanding plant carotenoid metabolism and breeding colourful carrot cultivars.
CYP97C1作为一种含血红素的细胞色素P450羟化酶（P450类型），对胡萝卜素羟化和叶黄素生物合成至关重要。关于这类羟化酶的研究主要在几种没有专门组织积累大量类胡萝卜素的模式植物物种中报道。CYP97C1在园艺植物如胡萝卜中的功能尚未得到充分研究。在本研究中，我们聚焦于DcCYP97C1在胡萝卜类胡萝卜素通量和颜色形成中的作用。发现DcCYP97C1在胡萝卜主根的“转变期”高度表达。利用稳定转化和CRISPR/Cas9介导的基因敲除技术，证实DcCYP97C1是叶黄素生物合成的限速酶，对主根颜色形成很重要。在橙色胡萝卜KRD（黑田五寸）中过表达DcCYP97C1导致叶黄素产量增加五倍，同时胡萝卜素显著减少。在橙色KRD和黄色胡萝卜QTH（齐头黄）中敲除DcCYP97C1会减少包括叶黄素、α-胡萝卜素和β-胡萝卜素在内的各种类胡萝卜素，这反映了DcCYP97C1在主根“转变期”类胡萝卜素总积累中的关键作用。我们的研究表明，对DcCYP97C1的调控足以影响类胡萝卜素通量、改变胡萝卜颜色并用于高叶黄素生产。DcCYP97C1所揭示的作用可能有助于理解植物类胡萝卜素代谢以及培育彩色胡萝卜品种。
