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Jin Y, Tang R, Wang H, Jiang C, Bao Y, Yang Y, Liang M, Sun Z, Kong F, Li B, Zhang H. Overexpression of Populus trichocarpa CYP85A3 promotes growth and biomass production in transgenic trees. PLANT BIOTECHNOLOGY JOURNAL 2017; 15:1309-1321. [PMID: 28258966 PMCID: PMC5595715 DOI: 10.1111/pbi.12717] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/11/2017] [Accepted: 02/20/2017] [Indexed: 05/19/2023]
Abstract
Brassinosteroids (BRs) are essential hormones that play crucial roles in plant growth, reproduction and response to abiotic and biotic stress. In Arabidopsis, AtCYP85A2 works as a bifunctional cytochrome P450 monooxygenase to catalyse the conversion of castasterone to brassinolide, a final rate-limiting step in the BR-biosynthetic pathway. Here, we report the functional characterizations of PtCYP85A3, one of the three AtCYP85A2 homologous genes from Populus trichocarpa. PtCYP85A3 shares the highest similarity with AtCYP85A2 and can rescue the retarded-growth phenotype of the Arabidopsis cyp85a2-2 and tomato dx mutants. Constitutive expression of PtCYP85A3, driven by the cauliflower mosaic virus 35S promoter, increased the endogenous BR levels and significantly promoted the growth and biomass production in both transgenic tomato and poplar. Compared to the wild type, plant height, shoot fresh weight and fruit yield increased 50%, 56% and 43%, respectively, in transgenic tomato plants. Similarly, plant height and stem diameter increased 15% and 25%, respectively, in transgenic poplar plants. Further study revealed that overexpression of PtCYP85A3 enhanced xylem formation without affecting the composition of cellulose and lignin, as well as the cell wall thickness in transgenic poplar. Our finding suggests that PtCYP85A3 could be used as a potential candidate gene for engineering fast-growing trees with improved wood production.
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Affiliation(s)
- Yan‐Li Jin
- College of AgricultureLudong UniversityYantaiChina
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of sciencesBeijingChina
| | - Ren‐Jie Tang
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Hai‐Hai Wang
- College of AgricultureLudong UniversityYantaiChina
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Chun‐Mei Jiang
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Yan Bao
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Yang Yang
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | | | - Zhen‐Cang Sun
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Fan‐Jing Kong
- MLR Key Laboratory of Saline Lake Resources and EnvironmentsInstitute of Mineral ResourcesCAGSBeijingChina
| | - Bei Li
- College of AgricultureLudong UniversityYantaiChina
| | - Hong‐Xia Zhang
- College of AgricultureLudong UniversityYantaiChina
- National Key Laboratory of Plant Molecular GeneticsShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
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Wang C, Yang Y, Wang H, Ran X, Li B, Zhang J, Zhang H. Ectopic expression of a cytochrome P450 monooxygenase gene PtCYP714A3 from Populus trichocarpa reduces shoot growth and improves tolerance to salt stress in transgenic rice. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1838-51. [PMID: 26970512 PMCID: PMC5069455 DOI: 10.1111/pbi.12544] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/02/2016] [Accepted: 01/22/2016] [Indexed: 05/03/2023]
Abstract
In Arabidopsis thaliana and Oryza sativa, the cytochrome P450 (CYP) 714 protein family represents a unique group of CYP monooxygenase, which functions as a shoot-specific regulator in plant development through gibberellin deactivation. Here, we report the functional characterizations of PtCYP714A3, an OsCYP714D1/Eui homologue from Populus trichocarpa. PtCYP714A3 was ubiquitously expressed with the highest transcript level in cambium-phloem tissues, and was greatly induced by salt and osmotic stress in poplar. Subcellular localization analyses indicated that PtCYP714A3-YFP fusion protein was targeted to endoplasmic reticulum (ER). Expression of PtCYP714A3 in the rice eui mutant could rescue its excessive-shoot-growth phenotype. Ectopic expression of PtCYP714A3 in rice led to semi-dwarfed phenotype with promoted tillering and reduced seed size. Transgenic lines which showed significant expression of PtCYP714A3 also accumulated lower GA level than did the wild-type (WT) plants. The expression of some GA biosynthesis genes was significantly suppressed in these transgenic plants. Furthermore, transgenic rice plants exhibited enhanced tolerance to salt and maintained more Na(+) in both shoot and root tissues under salinity stress. All these results not only suggest a crucial role of PtCYP714A3 in shoot responses to salt toxicity in rice, but also provide a molecular basis for genetic engineering of salt-tolerant crops.
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Affiliation(s)
- Cuiting Wang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Yang Yang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Haihai Wang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Xiaojuan Ran
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Bei Li
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Jiantao Zhang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Hongxia Zhang
- National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
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Wang C, Bao Y, Wang Q, Zhang H. Introduction of the rice CYP714D1 gene into Populus inhibits expression of its homologous genes and promotes growth, biomass production and xylem fibre length in transgenic trees. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:2847-57. [PMID: 23667043 PMCID: PMC3697953 DOI: 10.1093/jxb/ert127] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The rice (Oryza sativa) OsCYP714D1 gene (also known as EUI) encodes a cytochrome P450 monooxygenase which functions as a gibberellin (GA)-deactivating enzyme, catalysing 16α, 17-epoxidation of non-13-hydroxylated GAs. To understand whether it would also reduce the production of active GAs and depress the growth rate in transgenic trees, we constitutively expressed OsCYP714D1 in the aspen hybrid clone Populus alba×P. berolinensis. Unexpectedly, ectopic expression of OsCYP714D1 in aspen positively regulated the biosynthesis of GAs, including the active GA1 and GA4, leading to promotion of the growth rate and biomass production in transgenic plants. Transgenic lines which showed significant expression of the introduced OsCYP714D1 gene accumulated a higher GA level and produced more numerous and longer xylem fibres than did the wild-type plants. Quantitative real-time PCR indicated that transcription of most homologous PtCYP714 genes was suppressed in these transgenic lines. Therefore, the promoted GA and biomass production in transgenic trees constitutively expressing OsCYP714D1 is probably attributed to the down-regulated expression of the native PtCYP714 homologues involved in the GA biosynthesis pathway, although their precise functions are yet to be further elucidated.
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Affiliation(s)
| | | | - Qiuqing Wang
- Present address: Department of Cell Biology, The Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
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Logan BA, Reblin JS, Zonana DM, Dunlavey RF, Hricko CR, Hall AW, Schmiege SC, Butschek RA, Duran KL, Emery RJN, Kurepin LV, Lewis JD, Pharis RP, Phillips NG, Tissue DT. Impact of eastern dwarf mistletoe (Arceuthobium pusillum) on host white spruce (Picea glauca) development, growth and performance across multiple scales. PHYSIOLOGIA PLANTARUM 2013; 147:502-13. [PMID: 22905764 DOI: 10.1111/j.1399-3054.2012.01681.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 06/13/2012] [Accepted: 06/18/2012] [Indexed: 05/12/2023]
Abstract
Infection by eastern dwarf mistletoe (Arceuthobium pusillum) modifies needle and branch morphology and hastens white spruce (Picea glauca) mortality. We examined potential causal mechanisms and assessed the impacts of infection-induced alterations to host development and performance across scales ranging from needle hormone contents to bole expansion. Needles on infected branches (IBs) possessed higher total cytokinin (CK) and lower abscisic acid contents than needles on uninfected branches (UBs). IBs exhibited greater xylem growth than same-aged UBs, which is consistent with the promotive effect of CKs on vascular differentiation and organ sink strength. Elevated CK content may also explain the dense secondary and tertiary branching observed at the site of infection, i.e. the formation of 'witches' brooms' with significantly lower light capture efficiencies. Observed hormone perturbations were consistent with higher rates of transpiration, lower water use efficiencies (WUEs) and more negative needle carbon isotope ratios observed for IBs. Observed reductions in needle size allowed IBs to compensate for reduced hydraulic conductivity. Severe infections resulted in dramatically decreased diameter growth of the bole. It seems likely that the modifications to host hormone contents by eastern dwarf mistletoe infection led white spruce trees to dedicate a disproportionate fraction of their photoassimilate and other resources to self-shaded branches with low WUE. This would have decreased the potential for fixed carbon accumulation, generating a decline in the whole-tree resource pool. As mistletoe infections grew in size and the number of IBs increased, this burden was manifested as increasingly greater reductions in bole growth.
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Affiliation(s)
- Barry A Logan
- Biology Department, Bowdoin College, Brunswick, ME 04011, USA.
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Elias AA, Busov VB, Kosola KR, Ma C, Etherington E, Shevchenko O, Gandhi H, Pearce DW, Rood SB, Strauss SH. Green revolution trees: semidwarfism transgenes modify gibberellins, promote root growth, enhance morphological diversity, and reduce competitiveness in hybrid poplar. PLANT PHYSIOLOGY 2012; 160:1130-44. [PMID: 22904164 PMCID: PMC3461535 DOI: 10.1104/pp.112.200741] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Semidwarfism has been used extensively in row crops and horticulture to promote yield, reduce lodging, and improve harvest index, and it might have similar benefits for trees for short-rotation forestry or energy plantations, reclamation, phytoremediation, or other applications. We studied the effects of the dominant semidwarfism transgenes GA Insensitive (GAI) and Repressor of GAI-Like, which affect gibberellin (GA) action, and the GA catabolic gene, GA 2-oxidase, in nursery beds and in 2-year-old high-density stands of hybrid poplar (Populus tremula × Populus alba). Twenty-nine traits were analyzed, including measures of growth, morphology, and physiology. Endogenous GA levels were modified in most transgenic events; GA(20) and GA(8), in particular, had strong inverse associations with tree height. Nearly all measured traits varied significantly among genotypes, and several traits interacted with planting density, including aboveground biomass, root-shoot ratio, root fraction, branch angle, and crown depth. Semidwarfism promoted biomass allocation to roots over shoots and substantially increased rooting efficiency with most genes tested. The increased root proportion and increased leaf chlorophyll levels were associated with changes in leaf carbon isotope discrimination, indicating altered water use efficiency. Semidwarf trees had dramatically reduced growth when in direct competition with wild-type trees, supporting the hypothesis that semidwarfism genes could be effective tools to mitigate the spread of exotic, hybrid, and transgenic plants in wild and feral populations.
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Zhang Y, Zhang B, Yan D, Dong W, Yang W, Li Q, Zeng L, Wang J, Wang L, Hicks LM, He Z. Two Arabidopsis cytochrome P450 monooxygenases, CYP714A1 and CYP714A2, function redundantly in plant development through gibberellin deactivation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 67:342-53. [PMID: 21457373 DOI: 10.1111/j.1365-313x.2011.04596.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The rice gene ELONGATED UPPERMOST INTERNODE1 (EUI1) encodes a P450 monooxygenase that epoxidizes gibberellins (GAs) in a deactivation reaction. The Arabidopsis genome contains a tandemly duplicated gene pair ELA1 (CYP714A1) and ELA2 (CYP714A2) that encode EUI homologs. In this work, we dissected the functions of the two proteins. ELA1 and ELA2 exhibited overlapping yet distinct gene expression patterns. We showed that while single mutants of ELA1 or ELA2 exhibited no obvious morphological phenotype, simultaneous elimination of ELA1 and ELA2 expression in ELA1-RNAi/ela2 resulted in increased biomass and enlarged organs. By contrast, transgenic plants constitutively expressing either ELA1 or ELA2 were dwarfed, similar to those overexpressing the rice EUI gene. We also discovered that overexpression of ELA1 resulted in a severe dwarf phenotype, while overexpression of ELA2 gave rise to a breeding-favored semi-dwarf phenotype in rice. Consistent with the phenotypes, we found that the ELA1-RNAi/ela2 plants increased amounts of biologically active GAs that were decreased in the internodes of transgenic rice with ELA1 and ELA2 overexpression. In contrast, the precursor GA(12) slightly accumulated in the transgenic rice, and GA(19) highly accumulated in the ELA2 overexpression rice. Taken together, our study strongly suggests that the two Arabidopsis EUI homologs subtly regulate plant growth most likely through catalyzing deactivation of bioactive GAs similar to rice EUI. The two P450s may also function in early stages of the GA biosynthetic pathway. Our results also suggest that ELA2 could be an excellent tool for molecular breeding for high yield potential in cereal crops.
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Affiliation(s)
- Yingying Zhang
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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King RW, Mander LN, Asp T, MacMillan CP, Blundell CA, Evans LT. Selective deactivation of gibberellins below the shoot apex is critical to flowering but not to stem elongation of Lolium. MOLECULAR PLANT 2008; 1:295-307. [PMID: 19825541 DOI: 10.1093/mp/ssm030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Gibberellins (GAs) cause dramatic increases in plant height and a genetic block in the synthesis of GA(1) explains the dwarfing of Mendel's pea. For flowering, it is GA(5) which is important in the long-day (LD) responsive grass, Lolium. As we show here, GA(1) and GA(4) are restricted in their effectiveness for flowering because they are deactivated by C-2 hydroxylation below the shoot apex. In contrast, GA(5) is effective because of its structural protection at C-2. Excised vegetative shoot tips rapidly degrade [14C]GA(1), [14C]GA(4), and [14C]GA(20) (>80% in 6 h), but not [14C]GA(5). Coincidentally, genes encoding two 2beta-oxidases and a putative 16-17-epoxidase were most expressed just below the shoot apex (<3 mm). Further down the immature stem (>4 mm), expression of these GA deactivation genes is reduced, so allowing GA(1) and GA(4) to promote sub-apical stem elongation. Subsequently, GA degradation declines in florally induced shoot tips and these GAs can become active for floral development. Structural changes which stabilize GA(4) confirm the link between florigenicity and restricted GA 2beta-hydroxylation (e.g. 2alpha-hydroxylation and C-2 di-methylation). Additionally, a 2-oxidase inhibitor (Trinexapac Ethyl) enhanced the activity of applied GA(4), as did limiting C-16,17 epoxidation in 16,17-dihydro GAs or after C-13 hydroxylation. Overall, deactivation of GA(1) and GA(4) just below the shoot apex effectively restricts their florigenicity in Lolium and, conversely, with GA(5), C-2 and C-13 protection against deactivation allows its high florigenicity. Speculatively, such differences in GA access to the shoot apex of grasses may be important for separating floral induction from inflorescence emergence and thus could influence their survival under conditions of herbivore predation.
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Affiliation(s)
- Rod W King
- CSIRO, Plant Industry, Canberra, ACT 2600, Australia.
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Busov V, Meilan R, Pearce DW, Rood SB, Ma C, Tschaplinski TJ, Strauss SH. Transgenic modification of gai or rgl1 causes dwarfing and alters gibberellins, root growth, and metabolite profiles in Populus. PLANTA 2006; 224:288-99. [PMID: 16404575 DOI: 10.1007/s00425-005-0213-9] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Accepted: 12/10/2005] [Indexed: 05/06/2023]
Abstract
In Arabidopsis and other plants, gibberellin (GA)-regulated responses are mediated by proteins including GAI, RGA and RGL1-3 that contain a functional DELLA domain. Through transgenic modification, we found that DELLA-less versions of GAI (gai) and RGL1 (rgl1) in a Populus tree have profound, dominant effects on phenotype, producing pleiotropic changes in morphology and metabolic profiles. Shoots were dwarfed, likely via constitutive repression of GA-induced elongation, whereas root growth was promoted two- to threefold in vitro. Applied GA(3 )inhibited adventitious root production in wild-type poplar, but gai/rgl1 poplars were unaffected by the inhibition. The concentrations of bioactive GA(1) and GA(4) in leaves of gai- and rgl1-expressing plants increased 12- to 64-fold, while the C(19) precursors of GA(1) (GA(53), GA(44) and GA(19)) decreased three- to ninefold, consistent with feedback regulation of GA 20-oxidase in the transgenic plants. The transgenic modifications elicited significant metabolic changes. In roots, metabolic profiling suggested increased respiration as a possible mechanism of the increased root growth. In leaves, we found metabolite changes suggesting reduced carbon flux through the lignin biosynthetic pathway and a shift towards allocation of secondary storage and defense metabolites, including various phenols, phenolic glucosides, and phenolic acid conjugates.
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Affiliation(s)
- Victor Busov
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, 49931-1295, USA.
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Zhu Y, Nomura T, Xu Y, Zhang Y, Peng Y, Mao B, Hanada A, Zhou H, Wang R, Li P, Zhu X, Mander LN, Kamiya Y, Yamaguchi S, He Z. ELONGATED UPPERMOST INTERNODE encodes a cytochrome P450 monooxygenase that epoxidizes gibberellins in a novel deactivation reaction in rice. THE PLANT CELL 2006; 18:442-56. [PMID: 16399803 PMCID: PMC1356550 DOI: 10.1105/tpc.105.038455] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The recessive tall rice (Oryza sativa) mutant elongated uppermost internode (eui) is morphologically normal until its final internode elongates drastically at the heading stage. The stage-specific developmental effect of the eui mutation has been used in the breeding of hybrid rice to improve the performance of heading in male sterile cultivars. We found that the eui mutant accumulated exceptionally large amounts of biologically active gibberellins (GAs) in the uppermost internode. Map-based cloning revealed that the Eui gene encodes a previously uncharacterized cytochrome P450 monooxygenase, CYP714D1. Using heterologous expression in yeast, we found that EUI catalyzed 16alpha,17-epoxidation of non-13-hydroxylated GAs. Consistent with the tall and dwarfed phenotypes of the eui mutant and Eui-overexpressing transgenic plants, respectively, 16alpha,17-epoxidation reduced the biological activity of GA(4) in rice, demonstrating that EUI functions as a GA-deactivating enzyme. Expression of Eui appeared tightly regulated during plant development, in agreement with the stage-specific eui phenotypes. These results indicate the existence of an unrecognized pathway for GA deactivation by EUI during the growth of wild-type internodes. The identification of Eui as a GA catabolism gene provides additional evidence that the GA metabolism pathway is a useful target for increasing the agronomic value of crops.
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Affiliation(s)
- Yongyou Zhu
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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Busov VB, Meilan R, Pearce DW, Ma C, Rood SB, Strauss SH. Activation tagging of a dominant gibberellin catabolism gene (GA 2-oxidase) from poplar that regulates tree stature. PLANT PHYSIOLOGY 2003; 132:1283-91. [PMID: 12857810 PMCID: PMC167068 DOI: 10.1104/pp.103.020354] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2003] [Revised: 02/21/2003] [Accepted: 03/20/2003] [Indexed: 05/18/2023]
Abstract
We identified a dwarf transgenic hybrid poplar (Populus tremula x Populus alba) after screening of 627 independent activation-tagged transgenic lines in tissue culture, greenhouse, and field environments. The cause of the phenotype was a hyperactivated gene encoding GA 2-oxidase (GA2ox), the major gibberellin (GA) catabolic enzyme in plants. The mutation resulted from insertion of a strong transcriptional enhancer near the transcription start site. Overexpression of the poplar GA2ox gene (PtaGA2ox1) caused hyperaccumulation of mRNA transcripts, quantitative shifts in the spectrum of GAs, and similarity in phenotype to transgenic poplars that overexpress a bean (Phaseolus coccineus) GA2ox gene. The poplar PtaGA2ox1 sequence was most closely related to PsGA2ox2 from pea (Pisum sativum) and two poorly known GA2oxs from Arabidopsis (AtGA2ox4 and AtGA2ox5). The dwarf phenotype was reversible through gibberellic acid application to the shoot apex. Transgenic approaches to producing semidwarf trees for use in arboriculture, horticulture, and forestry could have significant economic and environmental benefits, including altered fiber and fruit production, greater ease of management, and reduced risk of spread in wild populations.
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Affiliation(s)
- Victor B Busov
- Department of Forest Science, Oregon State University, Corvallis, Oregon 97331-5752 (V.B.B., R.M., C.M., S.H.S.)
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