Chlorogenic acids (CGA; including 5-caffeoylquinic acid and its regio-isomers) in Taraxacum antungense Kitag. have antioxidant and anti-inflammatory properties and exert other pharmacological effects. T. antungense hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (TaHQT)1 and TaHQT2, which belong to the BAHD acyltransferase family, are candidates for synthesizing 5-caffeoylquinic acid and that have not been extensively characterized. In this study, we cloned the TaHQT1 and TaHQT2 genes and analysed the properties of the expressed enzymes both in vitro and in vivo. Quantitative reverse transcription PCR analysis revealed that TaHQT1 was highly expressed in the root, whereas the strongest TaHQT2 expression was observed in T. antungense leaves. In Nicotiana benthamiana leaf cells, TaHQT1 and TaHQT2 were localized at the cell periphery as well as in the cytoplasm and nucleus. The 5-caffeoylquinic acid concentrations in T. antungense calli were reduced by TaHQT1 and TaHQT2 knockdown relative to the control. Conversely, inoculation of T. antungense plants tissues with recombinant TaHQT1 and TaHQT2 increased 5-caffeoylquinic acid levels in situ. These in vitro and in vivo findings demonstrate that both HQTs are involved in regulating 5-caffeoylquinic acid biosynthesis in T. antungense, which can be exploited to increase 5-caffeoylquinic acid production in plants for medicinal or other beneficial purposes.

中文翻译：

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羟基肉桂酰辅酶A的体外评价：与5-咖啡酰奎宁酸生产相关的蒲公英中奎宁羟基肉桂酰转移酶的表达和调控

Taraxacum antungense Kitag 中的绿原酸（CGA；包括 5-咖啡酰奎宁酸及其区域异构体）。具有抗氧化和抗炎特性，并发挥其他药理作用。T.antungense hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (TaHQT)1 和 TaHQT2 属于 BAHD 酰基转移酶家族，是合成 5-咖啡酰奎宁酸的候选物，尚未得到广泛表征。在这项研究中，我们克隆了 TaHQT1 和 TaHQT2 基因，并在体外和体内分析了表达的酶的特性。定量逆转录 PCR 分析显示 TaHQT1 在根中高表达，而在 T. antungense 叶中观察到最强的 TaHQT2 表达。在本氏烟草叶细胞中，TaHQT1 和 TaHQT2 位于细胞外围以及细胞质和细胞核中。相对于对照，TaHQT1 和 TaHQT2 敲低使 T.antungense 愈伤组织中的 5-咖啡酰奎宁酸浓度降低。相反，用重组 TaHQT1 和 TaHQT2 接种 T.antungense 植物组织原位增加了 5-咖啡酰奎宁酸水平。这些体外和体内研究结果表明，这两种 HQT 都参与调节 T.antungense 中 5-咖啡酰奎宁酸的生物合成，可用于增加植物中 5-咖啡酰奎宁酸的产量，用于药用或其他有益目的。具有重组 TaHQT1 和 TaHQT2 的反义植物组织原位增加 5-咖啡酰奎宁酸水平。这些体外和体内研究结果表明，这两种 HQT 都参与调节 T.antungense 中 5-咖啡酰奎宁酸的生物合成，可用于增加植物中 5-咖啡酰奎宁酸的产量，用于药用或其他有益目的。具有重组 TaHQT1 和 TaHQT2 的反义植物组织原位增加 5-咖啡酰奎宁酸水平。这些体外和体内研究结果表明，这两种 HQT 都参与调节 T.antungense 中 5-咖啡酰奎宁酸的生物合成，可用于增加植物中 5-咖啡酰奎宁酸的产量，用于药用或其他有益目的。