Shen Wenyun, Wei Yangdou, Dauk Melanie, Zheng Zhifu, Zou Jitao
Plant Biotechnology Institute, National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK, Canada S7N OW9.
FEBS Lett. 2003 Feb 11;536(1-3):92-6. doi: 10.1016/s0014-5793(03)00033-4.
We report molecular characterization of an Arabidopsis gene encoding a mitochondrial FAD-dependent glycerol-3-phosphate dehydrogenase (FAD-GPDH) that oxidizes glycerol-3-phosphate (G-3-P) to dihydroxyacetone phosphate. We demonstrate through in vitro targeting assays that the encoded gene product can be imported into mitochondrial membrane systems. Enzyme activity of the protein was confirmed through heterologous expression in Escherichia coli. The Arabidopsis gene is expressed throughout plant development, but at the highest level during seed germination. We also show that expression of the Arabidopsis FAD-GPDH gene is coupled to oxygen consumption and affected by ABA and stress conditions. Together with an NAD(+)-dependent GPDH, this enzyme could form a G-3-P shuttle, as previously established in other eukaryotic organisms, and links cytosolic G-3-P metabolism to carbon source utilization and energy metabolism in plants.
我们报道了拟南芥中一个编码线粒体FAD依赖的3-磷酸甘油脱氢酶（FAD-GPDH）基因的分子特征，该酶可将3-磷酸甘油（G-3-P）氧化为磷酸二羟丙酮。我们通过体外靶向分析证明，编码的基因产物可导入线粒体膜系统。通过在大肠杆菌中的异源表达证实了该蛋白的酶活性。拟南芥基因在植物发育过程中均有表达，但在种子萌发时表达水平最高。我们还表明，拟南芥FAD-GPDH基因的表达与氧气消耗相关，并受脱落酸和胁迫条件的影响。与NAD(+)依赖的GPDH一起，这种酶可以形成一个G-3-P穿梭系统，正如先前在其他真核生物中所证实的那样，并将细胞质中的G-3-P代谢与植物中的碳源利用和能量代谢联系起来。
