Nitrate Acts as a Signal to Induce Organic Acid Metabolism and Repress Starch Metabolism in Tobacco.
Open Access
- 1 May 1997
- journal article
- Published by Oxford University Press (OUP) in Plant Cell
- Vol. 9 (5), 783-798
- https://doi.org/10.1105/tpc.9.5.783
Abstract
Nia30(145) transformants with very low nitrate reductase activity provide an in vivo screen to identify processes that are regulated by nitrate. Nia30(145) resembles nitrate-limited wild-type plants with respect to growth rate and protein and amino acid content but accumulates large amounts of nitrate when it is grown on high nitrate. The transcripts for nitrate reductase (NR), nitrite reductase, cytosolic glutamine synthetase, and glutamate synthase increased; NR and nitrite reductase activity increased in leaves and roots; and glutamine synthetase activity increased in roots. The transcripts for phosphoenolpyruvate carboxylase, cytosolic pyruvate kinase, citrate synthase, and NADP-isocitrate dehydrogenase increased; phosphoenolpyruvate carboxylase activity increased; and malate, citrate, isocitrate, and [alpha]-oxoglutarate accumulated in leaves and roots. There was a decrease of the ADP-glucose pyrophosphorylase transcript and activity, and starch decreased in the leaves and roots. After adding 12 mM nitrate to nitrate-limited Nia30(145), the transcripts for NR and phosphoenolpyruvate carboxylase increased, and the transcripts for ADP-glucose pyrophosphorylase decreased within 2 and 4 hr, respectively. Starch was remobilized at almost the same rate as in wild-type plants, even though growth was not stimulated in Nia30(145). It is proposed that nitrate acts as a signal to initiate coordinated changes in carbon and nitrogen metabolism.This publication has 35 references indexed in Scilit:
- THE MOLECULAR-GENETICS OF NITROGEN ASSIMILATION INTO AMINO ACIDS IN HIGHER PLANTSAnnual Review of Plant Physiology and Plant Molecular Biology, 1996
- ROLE AND REGULATION OF SUCROSE-PHOSPHATE SYNTHASE IN HIGHER PLANTSAnnual Review of Plant Physiology and Plant Molecular Biology, 1996
- Simultaneous Measurement of Intracellular pH and K+ or NO3- in Barley Root Cells Using Triple-Barreled, Ion-Selective MicroelectrodesPlant Physiology, 1995
- In Vivo Regulation of Wheat-Leaf Phosphoenolpyruvate Carboxylase by Reversible PhosphorylationPlant Physiology, 1995
- Root- and shoot-specific responses of individual glutamine synthetase genes of maize to nitrate and ammoniumPublished by Springer Science and Business Media LLC ,1994
- Posttranslational Regulation of Nitrate Reductase in Higher PlantsPlant Physiology, 1994
- Effects of Nitrate and Ammonium on Gene Expression of Phosphoenolpyruvate Carboxylase and Nitrogen Metabolism in Maize Leaf Tissue during Recovery from Nitrogen StressPlant Physiology, 1992
- One of two different ADP-glucose pyrophosphorylase genes from potato responds strongly to elevated levels of sucroseMolecular Genetics and Genomics, 1990
- Carbon Accumulation during Photosynthesis in Leaves of Nitrogen- and Phosphorus-Stressed CottonPlant Physiology, 1986
- Nitrate Uptake by Dark-grown Corn SeedlingsPlant Physiology, 1973