title: Nitric oxide modulates cadmium influx during cadmium-induced programmed cell death in tobacco BY-2 cells.
abstract: Nitric oxide (NO) is a bioactive gas and functions as a signaling molecule in plants exposed to diverse biotic and abiotic stresses including cadmium (Cd(2+)). Cd(2+) is a non-essential and toxic heavy metal, which has been reported to induce programmed cell death (PCD) in plants. Here, we investigated the role of NO in Cd(2+)-induced PCD in tobacco BY-2 cells (Nicotiana tabacum L. cv. Bright Yellow 2). In this work, BY-2 cells exposed to 150 microM CdCl(2) underwent PCD with TUNEL-positive nuclei, significant chromatin condensation and the increasing expression of a PCD-related gene Hsr203J. Accompanied with the occurring of PCD, the production of NO increased significantly. The supplement of NO by sodium nitroprusside (SNP) had accelerated the PCD, whereas the NO synthase inhibitor Nomega-nitro-L-arginine methyl ester hydrochloride (L-NAME) and NO-specific scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) alleviated this toxicity. To investigate the mechanism by which NO exerted its function, Cd(2+) concentration was measured subsequently. SNP led more Cd(2+) content than Cd(2+) treatment alone. By contrast, the prevention of NO by L-NAME decreased Cd(2+) accumulation. Using the scanning ion-selective electrode technique, we analyzed the pattern and rate of Cd(2+) fluxes. This analysis revealed the promotion of Cd(2+) influxes into cells by application of SNP, while L-NAME and cPTIO reduced the rate of Cd(2+) uptake or even resulted in net Cd(2+) efflux. Based on these founding, we concluded that NO played a positive role in CdCl(2)-induced PCD by modulating Cd(2+) uptake and thus promoting Cd(2+) accumulation in BY-2 cells.
authors.affiliation: Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Ma
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Xu
authors.forename: Hua
authors.initials: H
authors.lastname: Xu
authors.forename: Yanshan
authors.initials: Y
authors.lastname: Chen
authors.forename: Zhenyan
authors.initials: Z
authors.lastname: He
authors.forename: Mi
authors.initials: M
authors.lastname: Ma
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001692:Biological Transport / Q000187:drug effects*; D002104:Cadmium / Q000378:metabolism* / Q000633:toxicity*; D002478:Cells, Cultured; D020287:In Situ Nick-End Labeling; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D014026:Nicotiana / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D020030:Nitric Oxide Donors; D002104:Cadmium; D009599:Nitroprusside; D009569:Nitric Oxide
references.citation: New Phytol. 2009 Jun;182(4):851-862
references.pmid: 19646068
references.citation: Acta Oncol. 1993;32(4):417-24
references.pmid: 8369130
references.citation: Planta. 1992 Nov;188(4):601-10
references.pmid: 24178395
references.citation: Plant Physiol. 2009 Feb;149(2):1141-53
references.pmid: 19028881
references.citation: Plant Physiol. 1998 Apr 1;116(4):1393-401
references.pmid: 9536057
references.citation: Plant J. 2002 Nov;32(4):539-48
references.pmid: 12445125
references.citation: Toxicol Appl Pharmacol. 2009 Aug 1;238(3):201-8
references.pmid: 19409405
references.citation: Plant Cell. 2002 Sep;14(9):2233-49
references.pmid: 12215517
references.citation: Curr Opin Plant Biol. 2004 Aug;7(4):449-55
references.pmid: 15231269
references.citation: Plant Mol Biol. 2000 Oct;44(3):321-34
references.pmid: 11199391
references.citation: Methods Enzymol. 1994;233:240-50
references.pmid: 8015461
references.citation: Plant Mol Biol. 2004 Mar;54(4):613-22
references.pmid: 15316293
references.citation: Plant Physiol. 2009 Mar;149(3):1302-15
references.pmid: 19168643
references.citation: Plant Physiol. 2009 May;150(1):217-28
references.pmid: 19261736
references.citation: Nitric Oxide. 2005 Aug;13(1):1-9
references.pmid: 15908241
references.citation: Aquat Toxicol. 2009 May 5;92(3):179-86
references.pmid: 19251326
references.citation: Plant Mol Biol. 2000 Oct;44(3):359-68
references.pmid: 11199394
references.citation: Phytochemistry. 2008 Oct;69(14):2609-15
references.pmid: 18789805
references.citation: Planta. 2000 Jan;210(2):215-21
references.pmid: 10664127
references.citation: Development. 2004 Jun;131(11):2707-14
references.pmid: 15128654
references.citation: Proc Natl Acad Sci U S A. 2000 Apr 25;97(9):4956-60
references.pmid: 10781104
references.citation: Plant Physiol. 1998 Mar;116(3):1063-72
references.pmid: 9501139
references.citation: Plant Physiol. 2001 Jul;126(3):1196-204
references.pmid: 11457969
references.citation: Planta. 2009 Sep;230(4):599-610
references.pmid: 19557429
references.citation: Tree Physiol. 2009 Sep;29(9):1175-86
references.pmid: 19638360
references.citation: Plant Cell. 2002 Jun;14(6):1347-57
references.pmid: 12084831
references.citation: Mol Plant Microbe Interact. 1998 Jun;11(6):544-54
references.pmid: 9612953
references.citation: Plant J. 1994 Apr;5(4):507-21
references.pmid: 8012404
references.citation: Cell Biol Int. 2008 Dec;32(12):1521-9
references.pmid: 18801448
references.citation: Plant Cell Environ. 2008 Nov;31(11):1606-19
references.pmid: 18684242
references.citation: Plant Cell Environ. 2007 Jul;30(7):775-85
references.pmid: 17547650
references.citation: Plant Signal Behav. 2009 Mar;4(3):252-4
references.pmid: 19721766
references.citation: Curr Opin Plant Biol. 2009 Jun;12(3):364-72
references.pmid: 19501016
references.citation: J Exp Bot. 2002 Nov;53(378):2151-8
references.pmid: 12379781
references.citation: Lancet Oncol. 2006 Feb;7(2):119-26
references.pmid: 16455475
references.citation: Plant Physiol. 2009 Aug;150(4):1773-83
references.pmid: 19535476
references.citation: Planta. 2009 Sep;230(4):755-65
references.pmid: 19626338
references.citation: Plant J. 2001 Jun;26(5):495-507
references.pmid: 11439136
references.citation: Nitric Oxide. 2009 Jun;20(4):289-97
references.pmid: 19233306
references.citation: Nature. 1998 Aug 6;394(6693):585-8
references.pmid: 9707120
references.citation: Trends Plant Sci. 2005 Mar;10(3):117-22
references.pmid: 15749469
references.citation: J Plant Physiol. 2005 Dec;162(12):1319-30
references.pmid: 16425450
references.citation: New Phytol. 2009 Mar;181(4):759-776
references.pmid: 19192189