Control of Nitrate Reductase Activity in Barley Aleurone Layers
T. E. Ferrari,J. E. Varner +1 more
TLDR
Oxygen inhibited nitrite release in the anaerobic intact-tissue assay, but under aerobic conditions and in the presence of 2-heptyl-4-hydroxyquinoline-N-oxide or antimycin A, nitrate reduction increased to rates comparable to those observed under anaerobiosis.Abstract:
Nitrate reductase activity in barley (Hordeum vulgare L cv Himalaya) aleurone layers has been determined in the intact tissue, using two different methods The first method measures the rate of appearance of H(2) (18)O produced during the reduction of KN(18)O(3) The second assay measures excreted nitrite resulting from nitrate reduction under anaerobic conditions Nitrite production in this anaerobic, intact-tissue assay was dependent upon the presence of phosphate (pH 75) and was increased by ethanol and bisulfiteAfter ten hours of nitrate induction, nitrate reductase activities measured by the KN(18)O(3) assay are one-sixth, and those measured by the anaerobic intact-tissue assay are one-third, of those observed in cell-free extracts of aleurone layers Addition of ethanol to the anaerobic intact-tissue medium increased the rate of nitrate reduction to a level greater than that found in the cell-free assayOxygen inhibited nitrite release in the anaerobic intact-tissue assay However, under aerobic conditions and in the presence of 2-heptyl-4-hydroxyquinoline-N-oxide or antimycin A, nitrate reduction increased to rates comparable to those observed under anaerobiosis Neither of these electron transport inhibitors affected anaerobic nitrate reduction, though they were effective in inhibiting oxygen uptake in separate experimentsread more
Citations
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Journal ArticleDOI
Apoplastic Synthesis of Nitric Oxide by Plant Tissues
TL;DR: The data presented in this report strongly support the hypothesis that plant tissues also synthesize NO via the nonenzymatic reduction of apoplastic nitrite and may have possible significance for germinating grain and for plant roots.
Journal ArticleDOI
Nitric Oxide Acts as an Antioxidant and Delays Programmed Cell Death in Barley Aleurone Layers
TL;DR: The hypothesis that NO is a protective antioxidant in aleurone cells is supported by data that shows that treatment with GA in the presence of NO donors delays the loss of CAT and SOD, and α-Amylase secretion is stimulated slightly by NO donors.
Book ChapterDOI
Nitric oxide signaling in plants
TL;DR: In this article, peroxisomal and apoplastic NOS enzymes are predicted and shown to produce sufficient NO to inhibit photosynthetic electron transport, allowing nitrite accumulation.
Journal ArticleDOI
Regulation of nitrate reductase activity in higher plants
TL;DR: Nitrate reductase is one of the most important enzymes in the assimilation of exogenous nitrate—the predominant form of nitrogen available to green plants growing in soil.
Journal ArticleDOI
An early response to gibberellic Acid not requiring protein synthesis.
Yosef Ben-Tal,Joseph E. Varner +1 more
TL;DR: It is concluded that the GA(3)-dependent increase in phosphorylcholine glyceride transferase activity (which occurs within the first 4 hours ofGA(3) treatment) does not require RNA synthesis or protein synthesis.
References
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Journal ArticleDOI
Gibberellic Acid-Enhanced Synthesis and Release of α-Amylase and Ribonuclease by Isolated Barley and Aleurone Layers
TL;DR: Gibberellic acid enhances the synthesis of alpha-amylase in isolated aleurone layers of barley-seeds and enhances the formation of ribonuclease which increases linearly over a 48 hour period.
Journal ArticleDOI
Neurospora nitrate reductase: the role of phosphate flavine and cytochrome c reductase.
TL;DR: Evidence is presented which indicates that the phosphate accelerates electron transport by combining with the molybdenum of the enzyme, and it must be concluded that nitrate induces the formation of both TPNH-flavine reductase and FMNH 2 -nitrate reduct enzyme activities.
Journal ArticleDOI
Substrate Induction of Nitrate Reductase in Barley Aleurone Layers
TL;DR: Barley aleurone layers provide a convenient tissue for the study of both substrate- and hormone-induced enzyme formation, and the time course of this inhibition suggests that the inhibition may be a secondary one.