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Bou-Torrent J, Galstyan A, Gallemí M, Cifuentes-Esquivel N, Molina-Contreras MJ, Salla-Martret M, Jikumaru Y, Yamaguchi S, Kamiya Y, Martínez-García JF. Plant proximity perception dynamically modulates hormone levels and sensitivity in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2937-47. [PMID: 24609653 PMCID: PMC4056540 DOI: 10.1093/jxb/eru083] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The shade avoidance syndrome (SAS) refers to a set of plant responses initiated after perception by the phytochromes of light enriched in far-red colour reflected from or filtered by neighbouring plants. These varied responses are aimed at anticipating eventual shading from potential competitor vegetation. In Arabidopsis thaliana, the most obvious SAS response at the seedling stage is the increase in hypocotyl elongation. Here, we describe how plant proximity perception rapidly and temporally alters the levels of not only auxins but also active brassinosteroids and gibberellins. At the same time, shade alters the seedling sensitivity to hormones. Plant proximity perception also involves dramatic changes in gene expression that rapidly result in a new balance between positive and negative factors in a network of interacting basic helix-loop-helix proteins, such as HFR1, PAR1, and BIM and BEE factors. Here, it was shown that several of these factors act as auxin- and BR-responsiveness modulators, which ultimately control the intensity or degree of hypocotyl elongation. It was deduced that, as a consequence of the plant proximity-dependent new, dynamic, and local balance between hormone synthesis and sensitivity (mechanistically resulting from a restructured network of SAS regulators), SAS responses are unleashed and hypocotyls elongate.
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Affiliation(s)
- Jordi Bou-Torrent
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain
| | - Anahit Galstyan
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain
| | - Marçal Gallemí
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain
| | - Nicolás Cifuentes-Esquivel
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain
| | | | - Mercè Salla-Martret
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | | | - Yuji Kamiya
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | - Jaime F Martínez-García
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, 08193-Barcelona, Spain Institució Catalana de Recerca i Estudis Avançats, 08010-Barcelona, Spain
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Devoghalaere F, Doucen T, Guitton B, Keeling J, Payne W, Ling TJ, Ross JJ, Hallett IC, Gunaseelan K, Dayatilake GA, Diak R, Breen KC, Tustin DS, Costes E, Chagné D, Schaffer RJ, David KM. A genomics approach to understanding the role of auxin in apple (Malus x domestica) fruit size control. BMC PLANT BIOLOGY 2012; 12:7. [PMID: 22243694 PMCID: PMC3398290 DOI: 10.1186/1471-2229-12-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 01/13/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND Auxin is an important phytohormone for fleshy fruit development, having been shown to be involved in the initial signal for fertilisation, fruit size through the control of cell division and cell expansion, and ripening related events. There is considerable knowledge of auxin-related genes, mostly from work in model species. With the apple genome now available, it is possible to carry out genomics studies on auxin-related genes to identify genes that may play roles in specific stages of apple fruit development. RESULTS High amounts of auxin in the seed compared with the fruit cortex were observed in 'Royal Gala' apples, with amounts increasing through fruit development. Injection of exogenous auxin into developing apples at the start of cell expansion caused an increase in cell size. An expression analysis screen of auxin-related genes involved in auxin reception, homeostasis, and transcriptional regulation showed complex patterns of expression in each class of gene. Two mapping populations were phenotyped for fruit size over multiple seasons, and multiple quantitative trait loci (QTLs) were observed. One QTL mapped to a region containing an Auxin Response Factor (ARF106). This gene is expressed during cell division and cell expansion stages, consistent with a potential role in the control of fruit size. CONCLUSIONS The application of exogenous auxin to apples increased cell expansion, suggesting that endogenous auxin concentrations are at least one of the limiting factors controlling fruit size. The expression analysis of ARF106 linked to a strong QTL for fruit weight suggests that the auxin signal regulating fruit size could partially be modulated through the function of this gene. One class of gene (GH3) removes free auxin by conjugation to amino acids. The lower expression of these GH3 genes during rapid fruit expansion is consistent with the apple maximising auxin concentrations at this point.
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Affiliation(s)
- Fanny Devoghalaere
- The New Zealand Institute for Plant & Food Research Limited (PFR), Private Bag 92169, Auckland 1142, New Zealand
| | - Thomas Doucen
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Baptiste Guitton
- PFR, Private Bag 11600, Palmerston North 4442, New Zealand
- INRA, UMR AGAP, Equipe Architecture et Fonctionnement des Espèces Fruitières, Avenue Agropolis - TA-A-108/03, 34398 Montpellier Cedex 01, France
| | - Jeannette Keeling
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Wendy Payne
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Toby John Ling
- School of Plant Science, University of Tasmania, GPO Box 252-55, Hobart, Tasmania 7001, Australia
| | - John James Ross
- School of Plant Science, University of Tasmania, GPO Box 252-55, Hobart, Tasmania 7001, Australia
| | - Ian Charles Hallett
- The New Zealand Institute for Plant & Food Research Limited (PFR), Private Bag 92169, Auckland 1142, New Zealand
| | - Kularajathevan Gunaseelan
- The New Zealand Institute for Plant & Food Research Limited (PFR), Private Bag 92169, Auckland 1142, New Zealand
| | - GA Dayatilake
- PFR, Private Bag 1401, Havelock North 4157, New Zealand
| | - Robert Diak
- PFR, Old Mill Road, RD3, Motueka 7198, New Zealand
| | - Ken C Breen
- PFR, Private Bag 1401, Havelock North 4157, New Zealand
| | | | - Evelyne Costes
- INRA, UMR AGAP, Equipe Architecture et Fonctionnement des Espèces Fruitières, Avenue Agropolis - TA-A-108/03, 34398 Montpellier Cedex 01, France
| | - David Chagné
- PFR, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Robert James Schaffer
- The New Zealand Institute for Plant & Food Research Limited (PFR), Private Bag 92169, Auckland 1142, New Zealand
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Karine Myriam David
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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Ferro N, Bredow T, Jacobsen HJ, Reinard T. Route to Novel Auxin: Auxin Chemical Space toward Biological Correlation Carriers. Chem Rev 2010; 110:4690-708. [DOI: 10.1021/cr800229s] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Noel Ferro
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegeler Strasse 12, Bonn, Germany 53115 and Institute for Plant Genetics, Leibniz University of Hannover, Germany
| | - Thomas Bredow
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegeler Strasse 12, Bonn, Germany 53115 and Institute for Plant Genetics, Leibniz University of Hannover, Germany
| | - Hans-Jorg Jacobsen
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegeler Strasse 12, Bonn, Germany 53115 and Institute for Plant Genetics, Leibniz University of Hannover, Germany
| | - Thomas Reinard
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegeler Strasse 12, Bonn, Germany 53115 and Institute for Plant Genetics, Leibniz University of Hannover, Germany
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Fonti P, Solomonoff N, García-González I. Earlywood vessels of Castanea sativa record temperature before their formation. THE NEW PHYTOLOGIST 2007; 173:562-570. [PMID: 17244050 DOI: 10.1111/j.1469-8137.2006.01945.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The aim of this study was to identify the climatic signal contained in the earlywood vessel size of the ring-porous chestnut (Castanea sativa) and the physiological processes involved in the underlying mechanisms. In order to assign the encoded signal to a specific physiological process, bud phenology and vessel formation were monitored along an elevation transect and chronologies of the size of the first row of earlywood vessels were retrospectively correlated with 40 yr of early spring temperatures. The first vessels appeared in late April to early May, after encoding both a negative temperature signal in February-March (during tree quiescence) and a positive temperature signal in early April (at the time of resumption of shoot growth). We hypothesize that February and March temperatures affect cambial sensitivity to auxin, preconditioning tree responses later in the season. Furthermore, April temperature is related to tree activation whereby new hormone production fosters vessel expansion.
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Affiliation(s)
- Patrick Fonti
- Swiss Federal Research Institute WSL, Dendro-Sciences Research Unit, Subunit Palaeo-Ecology, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland
- WSL, Sottostazione Sud delle Alpi, Via Belsoggiorno 22, CH-6504 Bellinzona-Ravecchia, Switzerland
| | - Natalie Solomonoff
- WSL, Sottostazione Sud delle Alpi, Via Belsoggiorno 22, CH-6504 Bellinzona-Ravecchia, Switzerland
| | - Ignacio García-González
- Departamento de Botánica, Universidade de Santiago de Compostela, Escola Politécnica Superior - Campus de Lugo, E-27002 Lugo, Spain
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Valdés AE, Fernández B, Centeno ML. Hormonal changes throughout maturation and ageing in Pinus pinea. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2004; 42:335-340. [PMID: 15120119 DOI: 10.1016/j.plaphy.2004.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2003] [Accepted: 02/13/2004] [Indexed: 05/24/2023]
Abstract
Phytohormones, which are responsible for certain age-related changes in plants, play a major role throughout maturation and ageing. Previous results dealing with this topic allowed us to describe an ageing and vigour index in Pinus radiata based on a ratio between different forms of cytokinins (Cks). The aim of the present study was to extend the studies on the changes in the hormonal status throughout maturation and ageing to Stone pine (Pinus pinea L.). With this aim in mind, a number of Cks were analysed in addition to indole-3-acetic acid (IAA) and abscisic acid (ABA) in terminal buds, axillary buds and in the apical portion of needles collected from trees at different stages of development. The results showed an increasing pattern in the levels of various Cks similar to that found in previous studies on P. radiata. Although the maintenance of the same ratio as an ageing and vigour index was not ratified, these results seem to point to Cks as major hormones throughout maturation and related processes in conifers. The distribution of hormones between the two parts of the needle is also discussed.
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Affiliation(s)
- Ana Elisa Valdés
- Unidad de Fisiología Vegetal, Departamento de Biología de Organismos y Sistemas, Universidad de Oviedo, c/Catedrático Rodrigo Uría, s/n. 33071 Oviedo, Asturias, Spain
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O'Neill DP, Ross JJ. Auxin regulation of the gibberellin pathway in pea. PLANT PHYSIOLOGY 2002; 130:1974-82. [PMID: 12481080 PMCID: PMC166708 DOI: 10.1104/pp.010587] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2002] [Revised: 08/12/2002] [Accepted: 08/22/2002] [Indexed: 05/15/2023]
Abstract
The auxin indole-3-acetic acid (IAA) has been shown to promote the biosynthesis of the active gibberellin (GA(1)) in shoots of pea (Pisum sativum). We used northern analysis to investigate the timing of IAA-induced changes in transcript levels of PsGA3ox1 (Mendel's LE), PsGA2ox1, PsGA2ox2, and PsGA20ox1, key genes for the later stages of GA(1) biosynthesis and metabolism in pea. Rapid (2-4 h) changes occurred in the transcript levels of PsGA3ox1, PsGA2ox1, and PsGA2ox2 after treatment with IAA. [(14)C]GA(1) metabolism studies in decapitated shoots indicated that IAA inhibits GA(1) deactivation, consistent with the suppression of PsGA2ox1 (SLN) transcript levels by IAA. Studies with the sln mutant also indicated that PsGA2ox1 activity is involved in GA(1) deactivation in decapitated shoots. Culture of excised internode tissue in the presence of auxin clearly demonstrated that internode tissue is a site of GA(1) biosynthesis per se. Excised internode tissue cultured in the presence/absence of cycloheximide showed that de novo protein synthesis is required for IAA-induced increases in PsGA3ox1 transcript levels. Auxin dose response studies indicated that IAA concentration is a critical determinant of GA(1) biosynthesis over 1 to 2 orders of magnitude, and a range of auxins was shown to affect the GA pathway.
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Affiliation(s)
- Damian P O'Neill
- School of Plant Science, University of Tasmania, Hobart, Tasmania 7001, Australia
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8
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Klee H, Tieman D. The tomato ethylene receptor gene family: Form and function. PHYSIOLOGIA PLANTARUM 2002; 115:336-341. [PMID: 12081525 DOI: 10.1034/j.1399-3054.2002.1150302.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Phytohormones are essential for integrating many aspects of plant development and responses to the environment. Regulation of hormonally controlled events occurs at multiple levels: synthesis, catabolism and perception (Trewavas 1983, Bradford and Trewavas 1994). At the level of perception, sensitivity to hormones can be regulated both spatially and temporally during the life cycle. An example of spatial regulation is the differential response to a hormone that occurs during organ abscission. Temporally, sensitivity of an organ to a hormone may change during maturation, as occurs during fruit ripening. In this review, we will focus on the initial event in recognition of one hormone, ethylene. The ethylene receptor was the first plant hormone receptor to be unambiguously identified. Over the last few years, great progress has been made in elucidating the genes involved in ethylene action. Nonetheless, the mechanisms of signal transduction remain to be established. Here, we will address the status of the tomato receptor gene family and the evidence that regulation of receptor gene expression can influence the response of the plant to the hormone.
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Affiliation(s)
- Harry Klee
- University of Florida, Department of Horticultural Sciences, PO Box 110690, Gainesville, FL 32611 USA
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Weyers JDB, Paterson NW. Plant hormones and the control of physiological processes. THE NEW PHYTOLOGIST 2001; 152:375-407. [PMID: 33862994 DOI: 10.1046/j.0028-646x.2001.00281.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This review examines contemporary views of the role of plant hormones in the control of physiological processes. Past and present difficulties with nomenclature encapsulate the problems inherent in using the 'classic' hormone concept in plants, with their distinctive multicellular organization. Chemical control may be a more relevant notion. However, control may also reside in the responding tissue via changes in sensitivity, or as combined control, where response is dictated by both sensitivity and concentration. Criteria for demonstrating these modes of action are reviewed, as well as frameworks for deciding whether hormone transport is involved. Problems of measuring relevant hormone concentrations are discussed. Methods for measuring and comparing tissue sensitivity to hormones are outlined and relative control is introduced as a means of assessing the importance of hormonal control against a background of other influences. While animals and plants appear to have coinherited homologueous intracellular signalling systems, at the whole organism level modes of hormone action may diverge. It is postulated that the synthesis-transport-action mechanism of action may be just one of several possible ways that phytohormones could control physiological processes. Twelve separate roles are discussed, and it is suggested that some of these could operate simultaneously to the plant's advantage. Contents Summary 375 I. Introduction 376 II. The history of the hormone concept in plant systems 376 III. Issues of nomenclature 380 IV. The need for sound conceptual frameworks in plant hormone research 382 V. Development of criteria for chemical control 384 VI. Identification and quantitative analysis of plant hormones 387 VII. Hormone transport in plants 389 VIII. Hormone sensitivity and its quantification 390 IX. Roles of receptors, second messengers and signal amplification in hormone sensitivity changes 393 X. Relative control as a pivotal concept 395 XI. Diversity of physiological roles for chemical influences in plants 397 XII. Concluding remarks 400 Acknowledgements 402 References 402.
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Affiliation(s)
| | - Neil W Paterson
- School of Life Sciences, University of Dundee, Dundee, DD1 4HN, UK
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McIntyre GI. Control of plant development by limiting factors: A nutritional perspective. PHYSIOLOGIA PLANTARUM 2001; 113:165-175. [PMID: 12060293 DOI: 10.1034/j.1399-3054.2001.1130203.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
It is postulated that limiting nutritional factors play a major role in the regulation of some aspects of plant development, and can provide an alternative to mechanisms based on the concept of hormonal control. This hypothesis is consistent with experimental evidence of the role of water as a limiting factor in (1) seed maturation and viviparous germination, (2) the elongation and phototropism of hypocotyls and coleoptiles, (3) the NO3--induced germination of dormant seeds, and (4) the release of buds from correlative inhibition. Studies on the influence of nutrition on morphogenesis have shown that the relative amounts of nitrogen and carbohydrate can determine the path of bud development as a shoot or rhizome. There is also evidence that either NO3- or sugar can limit lateral root initiation, and it is postulated that they may influence this process by a combination of osmotic and nutritional effects. The close correlation between environmentally induced developmental responses and the associated changes in the water or nutritional status of the responsive tissues, together with increasing evidence of the role of water and nutrients as transmitted signals and as regulators of gene expression, are in good agreement with their postulated role as limiting factors in the regulation of plant development.
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Affiliation(s)
- Gordon I. McIntyre
- Agriculture and Agri-Food Canada, Saskatoon Research Centre, 107 Science Place, Saskatoon, Saskatchewan, Canada S7N 0X2
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Palme K, Gälweiler L. PIN-pointing the molecular basis of auxin transport. CURRENT OPINION IN PLANT BIOLOGY 1999; 2:375-381. [PMID: 10508762 DOI: 10.1016/s1369-5266(99)00008-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Significant advances in the genetic dissection of the auxin transport pathway have recently been made. Particularly relevant is the molecular analysis of mutants impaired in auxin transport and the subsequent cloning of genes encoding candidate proteins for the elusive auxin efflux carrier. These studies are thought to pave the way to the detailed understanding of the molecular basis of several important facets of auxin action.
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Affiliation(s)
- K Palme
- Max-Delbrück-Laboratorium in der Max-Planck-Gesellschaft, Carl-von-Linné-Weg 10, D-50829, Köln, Germany.
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Lachaud S, Catesson AM, Bonnemain JL. Structure and functions of the vascular cambium. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1999; 322:633-50. [PMID: 10505236 DOI: 10.1016/s0764-4469(99)80103-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Following a general outline on the functioning of the cambium, the authors review the data acquired over the last 20 years. The interest is focused on: i) the ultrastructural characteristics of the two kinds of initials; ii) the early structural, metabolic and molecular modifications occurring during the first stages of daughter cell differentiation into either xylem or phloem; iii) the complex rhythmic changes of structure, metabolism and activity undergone by cambial cells during the seasonal cycle; iv) the characteristics and control of the cessation of cambial activity in autumn and of its reactivation in spring; v) the main research approaches in cell and molecular biology presently open to the students of the cambial meristem.
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Affiliation(s)
- S Lachaud
- Laboratoire de physiologie et biochimie végétales, ESA 6161 CNSR, Université de Pointers, France
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Haga K, Iino M. Auxin-growth relationships in maize coleoptiles and pea internodes and control by auxin of the tissue sensitivity to auxin. PLANT PHYSIOLOGY 1998; 117:1473-1486. [PMID: 9701602 PMCID: PMC34910 DOI: 10.1104/pp.117.4.1473] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/1998] [Accepted: 05/18/1998] [Indexed: 05/22/2023]
Abstract
Growth of a zone of maize (Zea mays L.) coleoptiles and pea (Pisum sativum L.) internodes was greatly suppressed when the organ was decapitated or ringed at an upper position with the auxin transport inhibitor N-1-naphthylphthalamic acid (NPA) mixed with lanolin. The transport of apically applied 3H-labeled indole-3-acetic acid (IAA) was similarly inhibited by NPA. The growth suppressed by NPA or decapitation was restored by the IAA mixed with lanolin and applied directly to the zone, and the maximal capacity to respond to IAA did not change after NPA treatment, although it declined slightly after decapitation. The growth rate at IAA saturation was greater than the rate in intact, nontreated plants. It was concluded that growth is limited and controlled by auxin supplied from the apical region. In maize coleoptiles the sensitivity to IAA increased more than 3 times when the auxin level was reduced over a few hours with NPA treatment. This result, together with our previous result that the maximal capacity to respond to IAA declines in pea internodes when the IAA level is enhanced for a few hours, indicates that the IAA concentration-response relationship is subject to relatively slow adaptive regulation by IAA itself. The spontaneous growth recovery observed in decapitated maize coleoptiles was prevented by an NPA ring placed at an upper position of the stump, supporting the view that recovery is due to regenerated auxin-producing activity. The sensitivity increase also appeared to participate in an early recovery phase, causing a growth rate greater than in intact plants.
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Affiliation(s)
- K Haga
- Botanical Gardens, Faculty of Science, Osaka City University, Kisaichi, Katano-shi, Osaka 576, Japan
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Lashbrook CC, Tieman DM, Klee HJ. Differential regulation of the tomato ETR gene family throughout plant development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 15:243-52. [PMID: 9721682 DOI: 10.1046/j.1365-313x.1998.00202.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Ethylene perception in plants is co-ordinated by multiple hormone receptor candidates sharing sequence commonalties with prokaryotic environmental sensor proteins known as two-component regulators. Two tomato homologs of the Arabidopsis ethylene receptor ETR1 were cloned from a root cDNA library. Both cDNAs, termed LeETR1 and LeETR2, were highly homologous to ETR1, exhibiting approximately 90% deduced amino acid sequence similarity and 80% deduced amino acid sequence identity. LeETR1 and LeETR2 contained all the major structural elements of two-component regulators, including the response regulator motif absent in LeETR3, the gene encoding tomato NEVER RIPE (NR). Using RNase protection analysis, the mRNAs of LeETR1, LeETR2 and NR were quantified in tissues engaged in key processes of the plant life cycle, including seed germination, shoot elongation, leaf and flower senescence, floral abscission, fruit set and fruit ripening. LeETR1 was expressed constitutively in all plant tissues examined. LeETR2 mRNA was expressed at low levels throughout the plant but was induced in imbibing tomato seeds prior to germination and was down-regulated in elongating seedlings and senescing leaf petioles. NR expression was developmentally regulated in floral ovaries and ripening fruit. Notably, hormonal regulation of NR was highly tissue-specific. Ethylene biosynthesis induced NR mRNA accumulation in ripening fruit but not in elongating seedlings or in senescing leaves or flowers. Furthermore, the abundance of mRNAs for all three LeETR genes remained uniform in multiple plant tissues experiencing marked changes in ethylene sensitivity, including the cell separation layer throughout tomato flower abscission.
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Affiliation(s)
- C C Lashbrook
- Department of Horticultural Sciences, University of Florida, Gainesville 32611-0690, USA
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15
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Affiliation(s)
- H M Leyser
- The Plant Laboratory, Department of Biology, University of York, Box 373, York, YO1 5YW, UK.
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Walden R, Reiss B, Koncz C, Schell J. The impact of Ti-plasmid-derived gene vectors on the study of the mechanism of action of phytohormones. ANNUAL REVIEW OF PHYTOPATHOLOGY 1997; 35:45-66. [PMID: 15012514 DOI: 10.1146/annurev.phyto.35.1.45] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The molecular basis of tumor formation on dicotyledonous plants by Agrobacterium relies on the transfer to the plant cell of a unique segment of bacterial DNA, the T-DNA. The T-DNA contains genes that are active in the plant cell and encode hormone biosynthetic enzymes, or proteins that deregulate the cell's response to phytohormones. Study of this process has yielded not only knowledge of how alterations in phytohormone homeostasis can affect plant cell growth, but also has provided the essential tools to study phytohormone signaling in transgenic plants. Furthermore, T-DNA insertion into the plant genome forms the basis of gene tagging, a versatile method for isolating genes involved in phytohormone signal transduction and action.
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Affiliation(s)
- R Walden
- Max-Planck-Institut für Zuchtungsforschung, Cologne, Germany.
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Palme K. Molecular analysis of plant signaling elements: relevance of eukaryotic signal transduction models. INTERNATIONAL REVIEW OF CYTOLOGY 1992; 132:223-83. [PMID: 1555920 DOI: 10.1016/s0074-7696(08)62457-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- K Palme
- Max-Planck-Institut für Pflanzenzüchtung, Köln, Germany
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Palme K, Hesse T, Moore I, Campos N, Feldwisch J, Garbers C, Hesse F, Schell J. Hormonal modulation of plant growth: the role of auxin perception. Mech Dev 1991; 33:97-106. [PMID: 1851629 DOI: 10.1016/0925-4773(91)90076-i] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The organisation of growth and development in vascular plants appears to be highly adapted to meet the specific demands of a sessile, autotrophic habit. Many of the characteristic features of plant development are associated with the activities of five groups of phytohormones. Each of the phytohormones has the ability to influence fundamentally a remarkable variety of developmental and physiological processes. This ability has been widely documented but remains to be explained. Here we describe how recent breakthroughs in the analysis and understanding of eucaryotic signal transduction are being applied, in conjunction with technical advances in molecular genetics, to elucidate the molecular basis of the phytohormonal properties of auxin. Both auxin concentration, and the sensitivity of plant cells to this phytohormone have been implicated as important parameters in auxin action. We describe recent molecular biological approaches to assess the contribution made by each of these parameters. Emphasis is given to a description of recent genetic and biochemical progress towards identification of the molecular targets of the auxin signal and the molecular components involved in its subsequent transduction.
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Affiliation(s)
- K Palme
- Max-Planck-Institut für Züchtungsforschung, Cologne, F.R.G
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de Vries SC, Booij H, Janssens R, Vogels R, Saris L, LoSchiavo F, Terzi M, van Kammen A. Carrot somatic embryogenesis depends on the phytohormone-controlled presence of correctly glycosylated extracellular proteins. Genes Dev 1988. [DOI: 10.1101/gad.2.4.462] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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George Jones M. Gibberellins and the procera mutant of tomato. PLANTA 1987; 172:280-284. [PMID: 24225881 DOI: 10.1007/bf00394598] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/1987] [Accepted: 06/11/1987] [Indexed: 06/02/2023]
Abstract
The procera mutant of tomato (Lycopersicon esculentum L.) has a phenotype which is remarkably similar to that of normal tomatoes treated with exogenous gibberellin (GA), indicating that it might be a GA over-producer. However, analysis of endogenous GAs by gas chromatography-mass spectrometry showed that Procera actually has lower levels of GA20 and GA1 than normal. The reason for these anomalously low GA levels is not clear, as there was no difference between procera and normal plants in their ability to metabolize [(3)H]GA20. The procera mutant responded to exogenous gibberellic acid with increased extension growth, but the proportional response for a given dose of GA was the same in procera and normal plants. It therefore appears that the procera mutation does not directly affect either the GA status of the plant, or its ability to respond to GA.
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Affiliation(s)
- M George Jones
- Department of Biochemistry, University College of Wales, SY23 3DD, Aberystwyth, Dyfed, UK
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Schmidt S, Drumm-Herrel H, Oelmüller R, Mohr H. Time course of competence in phytochrome-controlled appearance of nuclear-encoded plastidic proteins and messenger RNAs. PLANTA 1987; 170:400-407. [PMID: 24232971 DOI: 10.1007/bf00395033] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/1986] [Accepted: 10/27/1986] [Indexed: 06/02/2023]
Abstract
The phytochrome-controlled expression of genes coding for plastidic proteins was studied in mustard (Sinapis alba L.) seedling cotyledons in continuous red (R) and far-red (FR) light, i.e. under steady-state conditions with regard to phytochrome, and in darkness over a time span of 8 d after sowing (25° C). (i) The time courses of the levels of the Calvin-cycle enzymes ribulose-1,5-bisphosphate carboxylase (RuBPCase) and NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (NADP-GPD) were found to be optimum curves. The time at which the optimum (peak) occurred was - independent of fluence rate - the same in R (strong phytochrome action, chlorophyll accumulation and photosynthesis) and FR (strong phytochrome action but no significant chlorophyll accumulation and no photosynthesis). The starting point (first detectable inccrease of enzyme level) was also endogenously fixed and not affected by light. However, the two enzymes differed insofar as the peak was at 4 d after sowing for RuBPCase activity and 4.5 d for GPD. Western blots of the small (SSU) and large (LSU) subunits of RuBPCase showed that enzyme activity and protein levels were correlated. It was concluded that a dramatic change of competence towards phytochrome had occurred and that this change was endogenous. This conclusion was confirmed by short-term induction experiments. In constant darkness (D) the low enzyme levels were saturation rather than optimum curves, presumably because enzyme turnover was lacking. (ii) The time course of accumulation of membrane components showed that chlorophyll and LHCP (light-harvesting chlorophyll a/b-binding protein of photosystem II) levels were closely correlated in R until 6 d after sowing. Thereafter the levels remained constant. The accumulation of membrane components was not related to the accumulation of Calvin-cycle enzymes. (iii) Time courses of the levels of translatable mRNAs, particularly SSU mRNA and LHCP mRNA were determined. In the case of SSU the maximum mRNA-level was found in R, FR and D around 3 d. This was compatible with the in-situ protein accumulation rate. Induction experiments with FR showed that accumulation of SSU mRNA followed the same rise and fall (peak at 3 d) as would be expected from the time course of mRNA levels and from enzyme-induction experiments. In the case of LHCP mRNA the peak was between 3 and 4 d in R, and was not well correlated with in-situ protein accumulation. Translatable LHCP mRNA was also formed in FR and in D-with a peak between 3 and 4 d-although LHCP protein was not detectable under these circumstances (because of the lack of chlorophyll). The data indicate that competence of gene expression towards phytochrome is determined endogenously. However, in the case of LHCP its appearance is not only limited by mRNA but also depends on the availability of chlorophyll.
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Affiliation(s)
- S Schmidt
- Biologisches Institut II der Universität, Schänzlestrasse 1, D-7800, Freiburg i. Br., Federal Republic of Germany
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Weyers JDB, Paterson NW, A'brook R. Towards a quantitative definition of plant hormone sensitivity. PLANT, CELL & ENVIRONMENT 1987; 10:1-10. [PMID: 28692151 DOI: 10.1111/j.1365-3040.1987.tb02073.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A definition of plant hormone sensitivity is proposed which is based on the initial rates of responses at different hormone concentrations. By analogy with enzyme kinetics, it is concluded that simple concentration-response curves can be described by a function containing three 'sensitivity parameters'. Objective methods for determining the values of these parameters and for comparing curves are described. These methods are used to describe the responses of Commelina communis L. stomata to abscisic acid. If certain assumptions are valid, the sensitivity parameters can be assigned physicochemical meanings. To validate the assumptions, certain experimental criteria must be fulfilled and these are discussed.
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Affiliation(s)
- J D B Weyers
- Department of Biological Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K.Department of Mathematical Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K
| | - N W Paterson
- Department of Biological Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K.Department of Mathematical Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K
| | - R A'brook
- Department of Biological Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K.Department of Mathematical Sciences, University of Dundee, Dundee DD1 4HN, Taysidc, U.K
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Affiliation(s)
- M L Evans
- Department of Botany, Ohio State University, Columbus, USA
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