Putrescine differently influences the effect of salt stress on polyamine metabolism and ethylene synthesis in rice cultivars differing in salt resistance.
Effects of salt stress on polyamine metabolism and ethylene production were examined in two rice (Oryza sativa L.) cultivars [I Kong Pao (IKP), salt sensitive; and Pokkali, salt resistant] grown for 5 d and 12 d in nutrient solution in the presence or absence of putrescine (1 mM) and 0, 50, and 100 mM NaCl. The salt-sensitive (IKP) and salt-resistant (Pokkali) cultivars differ not only in their mean levels of putrescine, but also in the physiological functions assumed by this molecule in stressed tissues. Salt stress increased the proportion of conjugated putrescine in salt-resistant Pokkali and decreased it in the salt-sensitive IKP, suggesting a possible protective function in response to NaCl. Activities of the enzymes ornithine decarboxylase (ODC; EC 4.1.1.17) and arginine decarboxylase (ADC; EC 4.1.1.19) involved in putrescine synthesis were higher in salt-resistant Pokkali than in salt-sensitive IKP. Both enzymes were involved in the response to salt stress. Salt stress also increased diamine oxidase (DAO; 1.4.3.6) and polyamine oxidase (PAO EC 1.5.3.11) activities in the roots of salt-resistant Pokkali and in the shoots of salt-sensitive IKP. Gene expression followed by reverse transcription-PCR suggested that putrescine could have a post-translational impact on genes coding for ADC (ADCa) and ODC (ODCa and ODCb) but could induce a transcriptional activation of genes coding for PAO (PAOb) mainly in the shoot of salt-stressed plants. The salt-resistant cultivar Pokkali produced higher amounts of ethylene than the salt-sensitive cultivar IKP, and exogenous putrescine increased ethylene synthesis in both cultivars, suggesting no direct antagonism between polyamine and ethylene pathways in rice.
Quinet
Muriel
M
Groupe de Recherche en Physiologie végétale (GRPV), Université catholique de Louvain, 5 (Bte 13) Place Croix du Sud, Louvain-la-Neuve, Belgium.
Ndayiragije
Alexis
A
Lefèvre
Isabelle
I
Lambillotte
Béatrice
B
Dupont-Gillain
Christine C
CC
Lutts
Stanley
S
D018533:Biomass; D002414:Cations, Monovalent / Q000378:metabolism; D005030:Ethylenes / Q000096:biosynthesis*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D012275:Oryza / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D009995:Osmosis / Q000187:drug effects; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D018520:Plant Shoots / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D011188:Potassium / Q000378:metabolism; D011700:Putrescine / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D055049:Salt Tolerance / Q000187:drug effects* / Q000235:genetics; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D013095:Spermidine / Q000378:metabolism; D013096:Spermine / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects*; D014867:Water / Q000378:metabolism
D002414:Cations, Monovalent; D005030:Ethylenes; D010940:Plant Proteins; D012333:RNA, Messenger; D014867:Water; D013096:Spermine; D012965:Sodium Chloride; D008315:Malondialdehyde; C036216:ethylene; D012964:Sodium; D011188:Potassium; D013095:Spermidine; D011700:Putrescine
Biochim Biophys Acta. 1961 Mar 18;48:182-6
13715498
Biochem J. 1996 Feb 15;314 ( Pt 1):241-8
8660289
Eur J Biochem. 1995 Feb 15;228(1):74-8
7883014
Plant Cell Physiol. 2004 Jun;45(6):712-22
15215506
Biochem J. 1988 Jan 1;249(1):33-6
3124824
Physiol Plant. 2008 Jun;133(2):140-56
18282192
J Exp Bot. 2006;57(1):101-11
16291800
Plant Physiol. 1997 Apr;113(4):1009-13
9112764
J Biosci. 2000 Sep;25(3):291-9
11022232
Trends Plant Sci. 2006 Feb;11(2):80-8
16406305
J Exp Bot. 2007;58(6):1545-55
17332417
Biochem Biophys Res Commun. 2006 Jun 30;345(2):646-51
16690022
Plant Physiol. 1996 Aug;111(4):1077-83
8756495
Methods Mol Biol. 2000;132:365-86
10547847
J Plant Physiol. 2004 Jan;161(1):35-42
15002662
J Plant Physiol. 2006 Mar;163(5):506-16
16473655
Anal Biochem. 1976 May 7;72:248-54
942051
Plant Mol Biol. 1997 Jun;34(3):477-83
9225858
Gene. 2004 Nov 24;342(2):199-209
15527979
EMBO J. 2004 Dec 8;23(24):4857-67
15538383
Physiol Plant. 2004 Jan;120(1):84-92
15032880
Arch Biochem Biophys. 1968 Apr;125(1):189-98
5655425
Plant Physiol. 1983 Jun;72(2):441-6
16663022
FEBS Lett. 2005 Feb 28;579(6):1435-40
15733853
J Exp Bot. 2006;57(6):1413-21
16556629
Amino Acids. 2008 Jan;34(1):35-45
17356805