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Shrestha A, Cudjoe DK, Kamruzzaman M, Siddique S, Fiorani F, Léon J, Naz AA. Abscisic acid-responsive element binding transcription factors contribute to proline synthesis and stress adaptation in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2021; 261:153414. [PMID: 33895677 DOI: 10.1016/j.jplph.2021.153414] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/19/2021] [Accepted: 03/31/2021] [Indexed: 06/12/2023]
Abstract
Proline accumulation is one of the most common adaptive responses of higher plants against abiotic stresses like drought. It plays multiple roles in osmotic adjustment, cell homeostasis and stress recovery. Genetic regulation of proline accumulation under drought is complex, and transcriptional cascades modulating proline is poorly understood. Here, we employed quadruple mutant (abf1 abf2 abf3 abf4) to dissect the role of ABA-responsive elements (ABREs) binding transcription factors (ABFs) in modulating proline accumulation across varying stress scenarios. ABREs are present across the promoter of the P5CS1 gene, whose upregulation is considered a hallmark for drought inducible proline accumulation. Upon ABA treatment, P5CS1 mRNA expression and proline content in the shoot were significantly higher in Col-0 compared to the quadruple mutant. Similar results were found at 2 h and 3 h after acute dehydration. We quantified proline at different time points after drought stress treatment. The proline content was higher in wild type (Col-0) than the quadruple mutant at the early stage of drought. Notably, the proline accumulation in wild type increased at a slower rate than the quadruple mutant 7 d after drought stress. Besides, the quadruple mutant displayed significant oxidative damage, low tissue turgidity and higher membrane damage under terminal drought stress. Both terminal drought stress and long-term constant water stress revealed substantial differences in growth rate between wild type and quadruple mutant. The study provides evidence that ABFs are involved in drought stress response, such as proline biosynthesis in Arabidopsis.
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Affiliation(s)
- Asis Shrestha
- Department of Plant Breeding, Institute of Crop Science and Resource Conservation, University of Bonn, Germany.
| | - Daniel Kingsley Cudjoe
- Department of Plant Breeding, Institute of Crop Science and Resource Conservation, University of Bonn, Germany.
| | - Mohammad Kamruzzaman
- Department of Plant Breeding, Institute of Crop Science and Resource Conservation, University of Bonn, Germany.
| | | | - Fabio Fiorani
- IBG-2- Plant Sciences, Forschungszentrum Jülich, Jülich, Germany.
| | - Jens Léon
- Department of Plant Breeding, Institute of Crop Science and Resource Conservation, University of Bonn, Germany.
| | - Ali Ahmad Naz
- Department of Plant Breeding, Institute of Crop Science and Resource Conservation, University of Bonn, Germany.
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Trovato M, Mattioli R, Costantino P. Multiple roles of proline in plant stress tolerance and development. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s12210-008-0022-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Bartels D, Sunkar R. Drought and Salt Tolerance in Plants. CRITICAL REVIEWS IN PLANT SCIENCES 2005. [PMID: 0 DOI: 10.1080/07352680590910410] [Citation(s) in RCA: 1041] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
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Oztur ZN, Talamé V, Deyholos M, Michalowski CB, Galbraith DW, Gozukirmizi N, Tuberosa R, Bohnert HJ. Monitoring large-scale changes in transcript abundance in drought- and salt-stressed barley. PLANT MOLECULAR BIOLOGY 2002; 48:551-73. [PMID: 11999834 DOI: 10.1023/a:1014875215580] [Citation(s) in RCA: 273] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Responses to drought and salinity in barley (Hordeum vulgare L. cv. Tokak) were monitored by microarray hybridization of 1463 DNA elements derived from cDNA libraries of 6 and 10 h drought-stressed plants. Functional identities indicated that many cDNAs in these libraries were associated with drought stress. About 38% of the transcripts were novel and functionally unknown. Hybridization experiments were analyzed for drought- and salinity-regulated sequences, with significant changes defined as a deviation from the control exceeding 2.5-fold. Responses of transcripts showed stress-dependent expression patterns and time courses. Nearly 15% of all transcripts were either up- or down-regulated under drought stress, while NaCl led to a change in 5% of the transcripts (24 h, 150 mM NaCl). Transcripts that showed significant up-regulation under drought stress are exemplified by jasmonate-responsive, metallothionein-like, late-embryogenesis-abundant (LEA) and ABA-responsive proteins. Most drastic down-regulation in a category was observed for photosynthesis-related functions. Up-regulation under both drought and salt stress was restricted to ESTs for metallothionein-like and LEA proteins, while increases in ubiquitin-related transcripts characterized salt stress. A number of functionally unknown transcripts from cDNA libraries of drought-stressed plants showed up-regulation by drought but down-regulation by salt stress, documenting how precisely transcript profiles report different growth conditions and environments.
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Affiliation(s)
- Z Neslihan Oztur
- Department of Biochemistry and Molecular Biophysics, University of Arizona, Biosciences West, Tucson 85721-0088, USA
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Chernys JT, Zeevaart JA. Characterization of the 9-cis-epoxycarotenoid dioxygenase gene family and the regulation of abscisic acid biosynthesis in avocado. PLANT PHYSIOLOGY 2000; 124:343-53. [PMID: 10982448 PMCID: PMC59148 DOI: 10.1104/pp.124.1.343] [Citation(s) in RCA: 203] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2000] [Accepted: 05/19/2000] [Indexed: 05/18/2023]
Abstract
Avocado (Persea americana Mill. cv Lula) is a climacteric fruit that exhibits a rise in ethylene as the fruit ripens. This rise in ethylene is followed by an increase in abscisic acid (ABA), with the highest level occurring just after the peak in ethylene production. ABA is synthesized from the cleavage of carotenoid precursors. The cleavage of carotenoid precursors produces xanthoxin, which can subsequently be converted into ABA via ABA-aldehyde. Indirect evidence indicates that the cleavage reaction, catalyzed by 9-cis-epoxycarotenoid dioxygenase (NCED), is the regulatory step in ABA synthesis. Three genes encoding NCED cleavage-like enzymes were cloned from avocado fruit. Two genes, PaNCED1 and PaNCED3, were strongly induced as the fruit ripened. The other gene, PaNCED2, was constitutively expressed during fruit ripening, as well as in leaves. This gene lacks a predicted chloroplast transit peptide. It is therefore unlikely to be involved in ABA biosynthesis. PaNCED1 was induced by water stress, but expression of PaNCED3 was not detectable in dehydrated leaves. Recombinant PaNCED1 and PaNCED3 were capable of in vitro cleavage of 9-cis-xanthophylls into xanthoxin and C(25)-apocarotenoids, but PaNCED2 was not. Taken together, the results indicate that ABA biosynthesis in avocado is regulated at the level of carotenoid cleavage.
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Affiliation(s)
- J T Chernys
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824-1312, USA
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Iuchi S, Kobayashi M, Yamaguchi-Shinozaki K, Shinozaki K. A stress-inducible gene for 9-cis-epoxycarotenoid dioxygenase involved in abscisic acid biosynthesis under water stress in drought-tolerant cowpea. PLANT PHYSIOLOGY 2000; 123:553-62. [PMID: 10859185 PMCID: PMC59023 DOI: 10.1104/pp.123.2.553] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/1999] [Accepted: 02/21/2000] [Indexed: 05/17/2023]
Abstract
Four cDNA clones named CPRD (cowpea responsive to dehydration) corresponding to genes that are responsive to dehydration were isolated using differential screening of a cDNA library prepared from 10-h dehydrated drought-tolerant cowpea (Vigna unguiculata) plants. One of the cDNA clones has a homology to 9-cis-epoxycarotenoid dioxygenase (named VuNCED1), which is supposed to be involved in abscisic acid (ABA) biosynthesis. The GST (glutathione S-transferase)-fused protein indicates a 9-cis-epoxycarotenoid dioxygenase activity, which catalyzes the cleavage of 9-cis-epoxycarotenoid. The N-terminal region of the VuNCED1 protein directed the fused sGFP (synthetic green-fluorescent protein) into the plastids of the protoplasts, indicating that the N-terminal sequence acts as a transit peptide. Both the accumulation of ABA and expression of VuNCED1 were strongly induced by drought stress in the 8-d-old cowpea plant, whereas drought stress did not trigger the expression of VuABA1 (accession no. AB030295) gene that encodes zeaxanthin epoxidase. These results indicate that the VuNCED1 cDNA encodes a 9-cis-epoxycarotenoid dioxygenase and that its product has a key role in the synthesis of ABA under drought stress.
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Affiliation(s)
- S Iuchi
- Laboratory of Plant Molecular Biology, RIKEN Isukuba Institute, Tsukuba, Ibaraki, Japan
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Qin X, Zeevaart JA. The 9-cis-epoxycarotenoid cleavage reaction is the key regulatory step of abscisic acid biosynthesis in water-stressed bean. Proc Natl Acad Sci U S A 1999; 96:15354-61. [PMID: 10611388 PMCID: PMC24823 DOI: 10.1073/pnas.96.26.15354] [Citation(s) in RCA: 362] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/1999] [Indexed: 11/18/2022] Open
Abstract
Abscisic acid (ABA), a cleavage product of carotenoids, is involved in stress responses in plants. A well known response of plants to water stress is accumulation of ABA, which is caused by de novo synthesis. The limiting step of ABA biosynthesis in plants is presumably the cleavage of 9-cis-epoxycarotenoids, the first committed step of ABA biosynthesis. This step generates the C(15) intermediate xanthoxin and C(25)-apocarotenoids. A cDNA, PvNCED1, was cloned from wilted bean (Phaseolus vulgaris L.) leaves. The 2, 398-bp full-length PvNCED1 has an ORF of 615 aa and encodes a 68-kDa protein. The PvNCED1 protein is imported into chloroplasts, where it is associated with the thylakoids. The recombinant protein PvNCED1 catalyzes the cleavage of 9-cis-violaxanthin and 9'-cis-neoxanthin, so that the enzyme is referred to as 9-cis-epoxycarotenoid dioxygenase. When detached bean leaves were water stressed, ABA accumulation was preceded by large increases in PvNCED1 mRNA and protein levels. Conversely, rehydration of stressed leaves caused a rapid decrease in PvNCED1 mRNA, protein, and ABA levels. In bean roots, a similar correlation among PvNCED1 mRNA, protein, and ABA levels was observed. However, the ABA content was much less than in leaves, presumably because of the much smaller carotenoid precursor pool in roots than in leaves. At 7 degrees C, PvNCED1 mRNA and ABA were slowly induced by water stress, but, at 2 degrees C, neither accumulated. The results provide evidence that drought-induced ABA biosynthesis is regulated by the 9-cis-epoxycarotenoid cleavage reaction and that this reaction takes place in the thylakoids, where the carotenoid substrate is located.
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Affiliation(s)
- X Qin
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
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Zeevaart JA. Abscisic acid metabolism and its regulation. BIOCHEMISTRY AND MOLECULAR BIOLOGY OF PLANT HORMONES 1999. [DOI: 10.1016/s0167-7306(08)60488-3] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Audran C, Borel C, Frey A, Sotta B, Meyer C, Simonneau T, Marion-Poll A. Expression studies of the zeaxanthin epoxidase gene in nicotiana plumbaginifolia. PLANT PHYSIOLOGY 1998; 118:1021-8. [PMID: 9808747 PMCID: PMC34775 DOI: 10.1104/pp.118.3.1021] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/1998] [Accepted: 08/03/1998] [Indexed: 05/17/2023]
Abstract
Abscisic acid (ABA) is a plant hormone involved in the control of a wide range of physiological processes, including adaptation to environmental stress and seed development. In higher plants ABA is a breakdown product of xanthophyll carotenoids (C40) via the C15 intermediate xanthoxin. The ABA2 gene of Nicotiana plumbaginifolia encodes zeaxanthin epoxidase, which catalyzes the conversion of zeaxanthin to violaxanthin. In this study we analyzed steady-state levels of ABA2 mRNA in N. plumbaginifolia. The ABA2 mRNA accumulated in all plant organs, but transcript levels were found to be higher in aerial parts (stems and leaves) than in roots and seeds. In leaves ABA2 mRNA accumulation displayed a day/night cycle; however, the ABA2 protein level remained constant. In roots no diurnal fluctuation in mRNA levels was observed. In seeds the ABA2 mRNA level peaked around the middle of development, when ABA content has been shown to increase in many species. In conditions of drought stress, ABA levels increased in both leaves and roots. A concomitant accumulation of ABA2 mRNA was observed in roots but not in leaves. These results are discussed in relation to the role of zeaxanthin epoxidase both in the xanthophyll cycle and in the synthesis of ABA precursors.
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Affiliation(s)
- C Audran
- Laboratoire de Biologie Cellulaire, Institut National de la Recherche Agronomique, Route de St Cyr, 78026 Versailles cedex, France (C.A., A.F., C.M., A.M.-P.)
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Purification and Properties of Sucrose:Sucrose Fructosyltransferases from Barley Leaves and Onion Seeds. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/b978-0-444-89369-7.50029-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Saab IN, Sharp RE, Pritchard J, Voetberg GS. Increased endogenous abscisic Acid maintains primary root growth and inhibits shoot growth of maize seedlings at low water potentials. PLANT PHYSIOLOGY 1990; 93:1329-36. [PMID: 16667621 PMCID: PMC1062676 DOI: 10.1104/pp.93.4.1329] [Citation(s) in RCA: 148] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Roots of maize (Zea mays L.) seedlings continue to grow at low water potentials that cause complete inhibition of shoot growth. In this study, we have investigated the role of abscisic acid (ABA) in this differential growth sensitivity by manipulating endogenous ABA levels as an alternative to external applications of the hormone. An inhibitor of carotenoid biosynthesis (fluridone) and a mutant deficient in carotenoid biosynthesis (vp 5) were used to reduce the endogenous ABA content in the growing zones of the primary root and shoot at low water potentials. Experiments were performed on 30 to 60 hour old seedlings that were transplanted into vermiculite which had been preadjusted to water potentials of approximately -1.6 megapascals (roots) or -0.3 megapascals (shoots). Growth occurred in the dark at near-saturation humidity. Results of experiments using the inhibitor and mutant approaches were very similar. Reduced ABA content by either method was associated with inhibition of root elongation and promotion of shoot elongation at low water potentials, compared to untreated and wild-type seedlings at the same water potential. Elongation rates and ABA contents at high water potential were little affected. The inhibition of shoot elongation at low water potential was completely prevented in fluridone-treated seedlings during the first five hours after transplanting. The results indicate that ABA accumulation plays direct roles in both the maintenance of primary root elongation and the inhibition of shoot elongation at low water potentials.
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Affiliation(s)
- I N Saab
- Department of Agronomy, University of Missouri, Columbia, Missouri 65211
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Guerrero FD, Jones JT, Mullet JE. Turgor-responsive gene transcription and RNA levels increase rapidly when pea shoots are wilted. Sequence and expression of three inducible genes. PLANT MOLECULAR BIOLOGY 1990; 15:11-26. [PMID: 1715781 DOI: 10.1007/bf00017720] [Citation(s) in RCA: 128] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Reduction of turgor in pea shoots caused the accumulation of several poly(A) RNAs. cDNA clones derived from three different poly(A) RNAs which accumulate in wilted pea shoots were isolated, sequenced and expression of the corresponding genes examined. Clone 7a encoded a 289 amino acid protein. The C-terminal 180 amino acids of this protein were homologous to soybean nodulin-26. RNA hybridizing to cDNA 7a was abundant in roots, and induced in shoots by dehydration, heat shock and to a small extent by ABA. Hydropathic plots indicate that the protein encoded by cDNA 7a contains six potential membrane spanning domains similar to proteins which form ion channels. Clone 15a encoded a 363 amino acid protein with high homology to cysteine proteases. RNA hybridizing to cDNA 15a was more abundant in roots than shoots of control plants. Dehydration of pea shoots induced cDNA 15a mRNA levels whereas heat shock or ABA treatment did not. Clone 26g encoded a 508 amino acid protein with 30% residue identity to several aldehyde dehydrogenases. RNA hybridizing to cDNA 26g was induced by dehydration of shoots but not roots and heat shock and ABA did not modulate RNA levels. Levels of the three poly(A) RNAs increased 4-6-fold by 4 h after wilting and this increase was not altered by pretreatment of shoots with cycloheximide. When wilted shoots were rehydrated, RNA hybridizing to cDNA 26g declined to pre-stress levels within 2 h. Run-on transcription experiments using nuclei from pea shoots showed that transcription of the genes which encode the three poly(A) RNAs was induced within 30 min following reduction of shoot turgor. One of the genes showed a further increase in transcription by 4 h after dehydration whereas transcription of the other 2 genes declined. These results indicate that plant cells respond to changes in cell turgor by rapidly increasing transcription of several genes. Furthermore, the expression of the turgor-responsive genes varies with respect to the time course of induction and reversibility of the wilting-induced changes.
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Affiliation(s)
- F D Guerrero
- Department of Biochemistry and Biophysics, Texas A&M University, College Station 77843-2128
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Pesci P. Involvement of Cl in the Increase in Proline Induced by ABA and Stimulated by Potassium Chloride in Barley Leaf Segments. PLANT PHYSIOLOGY 1989; 89:1226-30. [PMID: 16666688 PMCID: PMC1056000 DOI: 10.1104/pp.89.4.1226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Stimulation by sodium or potassium chloride of the ABA-induced increase in proline was synergistically enhanced by CaCl(2) or MgCl(2) as well as by 1,3-bis[tris(hydroxymethyl)methylamino] propane chloride (BTP-Cl), N-methyl-d-glucamine chloride (NMG-Cl), or 2-amino-2-hydroxymethyl-1,3-propandiol chloride (TRIS-Cl). This enhancing effect did not depend on the osmolarity and occurred when Cl(-) was higher than K(+) in the incubation medium, but not vice versa. When CaCl(2) or MgCl(2) or NMG-Cl were added, the higher the Cl(-):K(+) ratio in the external solution the higher was the increase in proline. When the excess of Cl(-) to K(+) was obtained with BTP-Cl the highest enhancing effect resulted with a Cl(-):K(+) ratio of 3:1 while, at a 5:1 ratio, the KCl stimulation was completely suppressed. The inhibiting effect of proline accumulation by NH(4) (+) and 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene was reversed to varying degrees depending on the magnitude of the excess of Cl(-) on K(+) concentration in the medium. Also, the inhibition of proline accumulation obtained by tetraethylammonium chloride, monensin, and d-mannose was similarly reverted. These data suggest that Cl(-) elicits an increase in ABA-induced proline which needs the simultaneous presence of K(+) (or Na(+)) to take place.
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Affiliation(s)
- P Pesci
- Centro di Studio del C.N.R. per la Biologia Cellulare e Molecolare delle Piante, Università di Milano, Via G. Celoria 26, 20133 Milano, Italy
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Abstract
Foliar urea application on barley plants increased leaf urease activity for 5 hours with a peak of 20-fold at 2 hours. To discern the mode of urease induction, urea with or without inhibitors and [(35)S]methionine were incubated with leaf sections for different lengths of time. Urease was extracted, partially purified, electrophoresed, and then quantified by fluorogram. Five urease (U) isozymes were separated by PAGE. U(a) and U(b) might be polymers or complexes that occurred only at the peak of induced activity. U(1) and U(2) appeared at 0.5 and 0.75 hour, respectively, after urea induction, peaked at 2 hours, and persisted only in treated leaves for several additional hours indicating that they are transient inducible forms. U(3) was the constitutive form present in control and treated leaves. Induction with cordycepin or cycloheximide completely prevented urea stimulated activity and nullified the existence of isozymes U(a), U(b), U(1), and U(2). (35)S-U(1), which was labeled in the last hour of induction, appeared on fluorogram 1 hour after induction, peaked at 2 hours, and declined at 3 hours. Results indicated that de novo synthesis of urease is activated by the influx of urea.
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Affiliation(s)
- Y Chen
- Crop Science Department, Oregon State University, Corvallis, Oregon 97331-3002
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Stewart CR, Voetberg G. Abscisic Acid accumulation is not required for proline accumulation in wilted leaves. PLANT PHYSIOLOGY 1987; 83:747-9. [PMID: 16665332 PMCID: PMC1056443 DOI: 10.1104/pp.83.4.747] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Leaves from dark-grown barley (Hordeum vulgare L. var Larker) seedlings grown in the presence and absence of fluridone were used to determine whether or not abscisic acid (ABA) accumulation was necessary for proline to accumulate in wilted tissue. Wilted tissue (polyethylene glycol-treated) leaves from fluridone-grown seedlings did not accumulate ABA but did accumulate proline at a rate that was not different from the non-fluridone-treated leaves. Thus ABA accumulation is not required for wilting-induced proline accumulation in barley leaves. Proline accumulation in wilted leaves from the wilty tomato (Lycopersicon esculentum) mutant, flacca, was compared to that in the wild type, Rheinlands Ruhm. Proline accumulated in wilted leaves from flacca. The rate of accumulation was faster in flacca compared to the rate in the wild type because the wilty mutant wilted faster. ABA accumulated in wilted leaves from the wild type but not in the wilty mutant. This result is a further confirmation that ABA accumulation is not required for wilting-induced proline accumulation. These results are significant in that proline accumulation in barley leaves can be induced independently by any one of three treatments: wilting, ABA, or salt.
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Affiliation(s)
- C R Stewart
- Department of Botany, Iowa State University, Ames, Iowa 50011
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