叶酸(folates)是一类水溶性B族维生素, 包括四氢叶酸(THF)及其衍生物, 是植物体中参与C1转移反应的重要辅酶。其在嘌呤、胸苷酸、DNA、氨基酸和蛋白质的生物合成以及甲基循环中发挥重要作用。近年来, 人们对叶酸在植物体内的功能又有了新发现。例如, 叶酸可通过结合核糖开关实现基因表达调控; 叶酸在苯丙氨酸转化为酪氨酸过程中可作为电子供体; 光裂合酶和植物隐花色素的叶酸辅酶可捕获光能; 此外, 叶酸还参与叶绿素的生物合成以及种子抗氧化胁迫等过程。该文详细综述了上述新发现, 并对植物体内叶酸功能的主要研究方向进行了展望。

Folates are water-soluble B-vitamins that contain tetrahydrofolate (THF) and its derivatives. In plants, they are essential cofactors in C1 metabolism, being involved in the formation of purines and thymidylates for DNA synthesis, production of amino acids and proteins. They play a central role in the methyl cycle. Novel functions of folates in plants have been discovered recently. For example, folates regulate gene expression by the riboswitch, work as the electron donor when phenylalanine is converted to tyrosine, and harvest light as the coenzyme of photolyase and plant cryptochrome. Moreover, folate is involved in chlorophyll biosynthesis and oxidative tolerance of seeds, for example. We review these discoveries and give prospects for plant folate research.