Functional analysis of novel transporter involved in intra-cellular transport of nicotine biosynthetic intermediates.

植物产生大量的次生代谢物。一些代谢物往往在药用植物的特定器官中高度积累。生物合成中间体在细胞内细胞器内的运动也被提出。然而，人们对代谢物如何跨膜运输以及这些运动如何参与代谢物的产生知之甚少。烟草T408是一种叶绿体定位的转运蛋白，可能调节细胞内的中间转运。我们通过获得烟草植株和培养细胞的稳定转化子来改变T408的表达水平。在茉莉酸处理下，转基因培养细胞比对照细胞产生更高水平的生物碱。这些数据表明，通过调节细胞中特定转运蛋白的表达水平，次生代谢物的产量增加。

Plants produce a large number of secondary metabolites. Some metabolites are often highly accumulated in particular organs of medicinal plants. The movement of biosynthetic intermediates within the organelles in a cell is also suggested. However, little is known how metabolites are transported across membranes and how these movements are involved in metabolite production. Tobacco T408 is a plastid-localized transporter which might regulate intermediate transport in a cell. We altered expression level of T408 by producing stable transformants of tobacco plants and cultured cells. Transgenic cultured cells produced higher level of alkaloids than control cells under jasmonate treatment. These data suggested that productions of secondary metabolites are increased by regulating the expression level of specific transporter in a cell.