These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Nitric oxide inhibits nitrate reductase activity in wheat leaves.
    Author: Rosales EP, Iannone MF, Groppa MD, Benavides MP.
    Journal: Plant Physiol Biochem; 2011 Feb; 49(2):124-30. PubMed ID: 21093280.
    Abstract:
    Nitrate reductase (NR), a committed enzyme in nitrate assimilation, is involved in the generation of nitric oxide (NO) in plants. In wheat leaf segments exposed to sodium nitroprusside (SNP) or S-nitrosoglutathione (GSNO), NR activity was significantly reduced to different degrees between 3 and 21 h, whereas its activity was partially recovered when the NO scavenger cPTIO was used. At 21 h, NR activity decreased from 38% with 10 μM SNP to 91% with 500 μM SNP, respect to the C values. S-nitrosoglutathione reduced NR activity between 18% and 26% only at 3 h. When added directly to the incubation solution, NR activity was quickly and strongly inhibited more than 90% by 10 or 50 μM SNP, whereas 10 μM GSNO reduced the enzyme activity an average of 50%, at 30 min of incubation. l-NAME and d-arginine (nitric oxide synthase (NOS) inhibitors) increased NR activity by 14% and 52% respectively, at 21 h of exposure, leading us to suppose that endogenous NOS-dependent NO formation could also be modulating NR activity. NR protein expression was not affected by 10 or 100 μM SNP at 3 or 21 h of incubation, whereas nitration of tyrosines was not detected in the NR protein. Nitrates, which content increased along the time in the tissues, could be exerting a role in this regulation.
    [Abstract] [Full Text] [Related] [New Search]