Identification of a mitochondrial glycerol-3-phosphate dehydrogenase from Arabidopsis thaliana: evidence for a mitochondrial glycerol-3-phosphate shuttle in plants.
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.
Shen
Wenyun
W
Plant Biotechnology Institute, National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK, Canada S7N OW9.
Wei
Yangdou
Y
Dauk
Melanie
M
Zheng
Zhifu
Z
Zou
Jitao
J
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000196:embryology / Q000201:enzymology* / Q000378:metabolism; D001692:Biological Transport; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D005994:Glycerophosphates / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology* / Q000378:metabolism; D008969:Molecular Sequence Data; D021381:Protein Transport; D018749:RNA, Plant / Q000096:biosynthesis; D016415:Sequence Alignment; D014158:Transcription, Genetic
D005994:Glycerophosphates; D018749:RNA, Plant; D005182:Flavin-Adenine Dinucleotide; C029620:alpha-glycerophosphoric acid; D005993:Glycerolphosphate Dehydrogenase; C471850:glycerol-3-phosphate dehydrogenase, FAD-dependent