College of Horticulture , Nanjing Agricultural University , Nanjing , Jiangsu 210095 , People's Republic of China.
J Agric Food Chem. 2019 May 29;67(21):5997-6006. doi: 10.1021/acs.jafc.9b00509. Epub 2019 May 14.
A fluoride export gene ( CsFEX) was newly found and isolated from Camellia sinensis, and its functions in detoxifying F were investigated in transgenic Escherichia coli and Arabidopsis thaliana. CsFEX contains two crcB domains, which is the typical structure in plants. The expression of CsFEX in C. sinensis is tissue-specific and related to maturity of leaves, and its expression is significantly induced by F treatments in different tissues of C. sinensis, particularly in leaves. Additionally, the growth of C. sinensis, E. coli, and A. thaliana can all be inhibited by F treatment. However, the growth of CsFEX-overexpression E. coli was increased with lower F content under F treatment compared to the control. Similarly, the germination and growth of CsFEX-overexpression A. thaliana were enhanced with lower F content under F treatment compared to the wild type. CsFEX relieves F toxicity in the transgenic E. coli and A. thaliana by alleviating F accumulation.
从茶树中发现并分离出一种氟化物外排基因（CsFEX），并在转基因大肠杆菌和拟南芥中研究了其解毒 F 的功能。CsFEX 含有两个 crcB 结构域，这是植物中典型的结构。CsFEX 在茶树中的表达具有组织特异性，与叶片成熟度有关，并且在茶树不同组织中受到 F 处理的显著诱导，特别是在叶片中。此外，茶树、大肠杆菌和拟南芥的生长都会受到 F 处理的抑制。然而，与对照相比，在 F 处理下，CsFEX 过表达大肠杆菌中较低的 F 含量下的生长增加。同样，与野生型相比，在 F 处理下，CsFEX 过表达拟南芥的萌发和生长增强。CsFEX 通过减轻 F 积累来缓解 F 毒性，从而减轻 F 毒性在转基因大肠杆菌和拟南芥中的毒性。
