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Nelissen H, Sun X, Rymen B, Jikumaru Y, Kojima M, Takebayashi Y, Abbeloos R, Demuynck K, Storme V, Vuylsteke M, De Block J, Herman D, Coppens F, Maere S, Kamiya Y, Sakakibara H, Beemster GT, Inzé D. The reduction in maize leaf growth under mild drought affects the transition between cell division and cell expansion and cannot be restored by elevated gibberellic acid levels. Plant Biotechnol J 2018; 16:615-627. [PMID: 28730636 PMCID: PMC5787831 DOI: 10.1111/pbi.12801] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/07/2017] [Accepted: 07/12/2017] [Indexed: 05/05/2023]
Abstract
Growth is characterized by the interplay between cell division and cell expansion, two processes that occur separated along the growth zone at the maize leaf. To gain further insight into the transition between cell division and cell expansion, conditions were investigated in which the position of this transition zone was positively or negatively affected. High levels of gibberellic acid (GA) in plants overexpressing the GA biosynthesis gene GA20-OXIDASE (GA20OX-1OE ) shifted the transition zone more distally, whereas mild drought, which is associated with lowered GA biosynthesis, resulted in a more basal positioning. However, the increased levels of GA in the GA20OX-1OE line were insufficient to convey tolerance to the mild drought treatment, indicating that another mechanism in addition to lowered GA levels is restricting growth during drought. Transcriptome analysis with high spatial resolution indicated that mild drought specifically induces a reprogramming of transcriptional regulation in the division zone. 'Leaf Growth Viewer' was developed as an online searchable tool containing the high-resolution data.
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Affiliation(s)
- Hilde Nelissen
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Xiao‐Huan Sun
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Bart Rymen
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Yusuke Jikumaru
- Growth Regulation Research GroupPlant Science CenterRIKENYokohamaJapan
| | - Mikko Kojima
- Plant Productivity Systems Research GroupPlant Science CenterRIKENYokohamaJapan
| | - Yumiko Takebayashi
- Plant Productivity Systems Research GroupPlant Science CenterRIKENYokohamaJapan
| | - Rafael Abbeloos
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Kirin Demuynck
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Veronique Storme
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Marnik Vuylsteke
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Jolien De Block
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Dorota Herman
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Frederik Coppens
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Steven Maere
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
| | - Yuji Kamiya
- Growth Regulation Research GroupPlant Science CenterRIKENYokohamaJapan
| | - Hitoshi Sakakibara
- Plant Productivity Systems Research GroupPlant Science CenterRIKENYokohamaJapan
| | - Gerrit T.S. Beemster
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
- Department of BiologyUniversity of AntwerpAntwerpBelgium
| | - Dirk Inzé
- Department of Plant Biotechnology and BioinformaticsGhent UniversityGentBelgium
- Center for Plant Systems BiologyVIBGentBelgium
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Furuhashi T, Sugitate K, Nakai T, Jikumaru Y, Ishihara G. Rapid profiling method for mammalian feces short chain fatty acids by GC-MS. Anal Biochem 2018; 543:51-54. [DOI: 10.1016/j.ab.2017.12.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/29/2017] [Accepted: 12/04/2017] [Indexed: 01/08/2023]
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Acheampong AK, Zheng C, Halaly T, Giacomelli L, Takebayashi Y, Jikumaru Y, Kamiya Y, Lichter A, Or E. Abnormal Endogenous Repression of GA Signaling in a Seedless Table Grape Cultivar with High Berry Growth Response to GA Application. Front Plant Sci 2017; 8:850. [PMID: 28596775 PMCID: PMC5442209 DOI: 10.3389/fpls.2017.00850] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 05/08/2017] [Indexed: 05/24/2023]
Abstract
Gibberellin (GA) application is routinely used in the table grape industry to increase berry size and cluster length. Although grapevine cultivars show a wide range of growth responsiveness to GA3 application, the reasons for these differences is unclear. To shed light on this issue, two commercial grapevine cultivars with contrasting berry response to GA were selected for comparative analysis, in which we tested if the differences in response: (1) is organ-specific or cultivar-related; (2) will be reflected in qualitative/quantitative differences in transcripts/proteins of central components of GA metabolism and signaling and levels of GA metabolites. Our results showed that in addition to the high response of its berries to GA, internodes and rachis of cv. Black finger (BF) presented a greater growth response compared to that of cv. Spring blush (SB). In agreement, the results exposed significant quantitative differences in GA signaling components in several organs of both cultivars. Exceptionally higher level of all three functional VvDELLA proteins was recorded in young BF organs, accompanied by elevated VvGID1 expression and lower VvSLY1b transcripts. Absence of seed traces, low endogenous GA quantities and lower expression of VvGA20ox4 and VvGA3ox3 were also recorded in berries of BF. Our results raise the hypothesis that, in young organs of BF, low expression of VvSLY1b may be responsible for the massive accumulation of VvDELLA proteins, which then leads to elevated VvGID1 levels. This integrated analysis suggests causal relationship between endogenous mechanisms leading to anomalous GA signaling repression in BF, manifested by high quantities of VvDELLA proteins, and greater growth response to GA application.
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Affiliation(s)
- Atiako K. Acheampong
- Department of Fruit Tree Sciences, Institute of Plant Sciences, Agricultural Research Organization, Volcani CenterBet Dagan, Israel
- Department of Horticulture, Faculty of Agriculture Environment and Food Sciences, The Hebrew University of JerusalemRehovot, Israel
| | - Chuanlin Zheng
- Department of Fruit Tree Sciences, Institute of Plant Sciences, Agricultural Research Organization, Volcani CenterBet Dagan, Israel
| | - Tamar Halaly
- Department of Fruit Tree Sciences, Institute of Plant Sciences, Agricultural Research Organization, Volcani CenterBet Dagan, Israel
| | - Lisa Giacomelli
- Research and Innovation Centre-Fondazione Edmund MachSan Michele all’Adige, Italy
| | | | | | | | - Amnon Lichter
- Institute of Postharvest and Food Sciences, Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani CenterBet Dagan, Israel
| | - Etti Or
- Department of Fruit Tree Sciences, Institute of Plant Sciences, Agricultural Research Organization, Volcani CenterBet Dagan, Israel
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Urano K, Maruyama K, Jikumaru Y, Kamiya Y, Yamaguchi-Shinozaki K, Shinozaki K. Analysis of plant hormone profiles in response to moderate dehydration stress. Plant J 2017; 90:17-36. [PMID: 27995695 DOI: 10.1111/tpj.13460] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 12/14/2016] [Accepted: 12/14/2016] [Indexed: 05/19/2023]
Abstract
Plant responses to dehydration stress are mediated by highly complex molecular systems involving hormone signaling and metabolism, particularly the major stress hormone abscisic acid (ABA) and ABA-dependent gene expression. To understand the roles of plant hormones and their interactions during dehydration, we analyzed the plant hormone profiles with respect to dehydration responses in Arabidopsis thaliana wild-type (WT) plants and ABA biosynthesis mutants (nced3-2). We developed a procedure for moderate dehydration stress, and then investigated temporal changes in the profiles of ABA, jasmonic acid isoleucine (JA-Ile), salicylic acid (SA), cytokinin (trans-zeatin, tZ), auxin (indole-acetic acid, IAA), and gibberellin (GA4 ), along with temporal changes in the expression of key genes involved in hormone biosynthesis. ABA levels increased in a bi-phasic pattern (at the early and late phases) in response to moderate dehydration stress. JA-Ile levels increased slightly in WT plants and strongly increased in nced3-2 mutant plants at 72 h after the onset of dehydration. The expression profiles of dehydration-inducible genes displayed temporal responses in an ABA-dependent manner. The early phase of ABA accumulation correlated with the expression of touch-inducible genes and was independent of factors involved in the major ABA regulatory pathway, including the ABA-responsive element-binding (AREB/ABF) transcription factor. JA-Ile, SA, and tZ were negatively regulated during the late dehydration response phase. Transcriptome analysis revealed important roles for hormone-related genes in metabolism and signaling during dehydration-induced plant responses.
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Affiliation(s)
- Kaoru Urano
- RIKEN Center for Sustainable Resource Science (CSRS), 3-1-1 Koyadai, Tsukuba, Ibaraki, 305-0074, Japan
| | - Kyonoshin Maruyama
- Japan International Research Center for Agricultural Sciences (JIRCAS), 1-1 Ohwashi, Tsukuba, Ibaraki, 305-8686, Japan
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Yuji Kamiya
- RIKEN Center for Sustainable Resource Science (CSRS), 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | | | - Kazuo Shinozaki
- RIKEN Center for Sustainable Resource Science (CSRS), 3-1-1 Koyadai, Tsukuba, Ibaraki, 305-0074, Japan
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Tamiru M, Takagi H, Abe A, Yokota T, Kanzaki H, Okamoto H, Saitoh H, Takahashi H, Fujisaki K, Oikawa K, Uemura A, Natsume S, Jikumaru Y, Matsuura H, Umemura K, Terry MJ, Terauchi R. A chloroplast-localized protein LESION AND LAMINA BENDING affects defence and growth responses in rice. New Phytol 2016; 210:1282-97. [PMID: 26864209 DOI: 10.1111/nph.13864] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/11/2015] [Indexed: 05/27/2023]
Abstract
Understanding how plants allocate their resources to growth or defence is of long-term importance to the development of new and improved varieties of different crops. Using molecular genetics, plant physiology, hormone analysis and Next-Generation Sequencing (NGS)-based transcript profiling, we have isolated and characterized the rice (Oryza sativa) LESION AND LAMINA BENDING (LLB) gene that encodes a chloroplast-targeted putative leucine carboxyl methyltransferase. Loss of LLB function results in reduced growth and yield, hypersensitive response (HR)-like lesions, accumulation of the antimicrobial compounds momilactones and phytocassanes, and constitutive expression of pathogenesis-related genes. Consistent with these defence-associated responses, llb shows enhanced resistance to rice blast (Magnaporthe oryzae) and bacterial blight (Xanthomonas oryzae pv. oryzae). The lesion and resistance phenotypes are likely to be caused by the over-accumulation of jasmonates (JAs) in the llb mutant including the JA precursor 12-oxo-phytodienoic acid. Additionally, llb shows an increased lamina inclination and enhanced early seedling growth due to elevated brassinosteroid (BR) synthesis and/or signalling. These findings show that LLB functions in the chloroplast to either directly or indirectly repress both JA- and BR-mediated responses, revealing a possible mechanism for controlling how plants allocate resources for defence and growth.
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Affiliation(s)
- Muluneh Tamiru
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | - Hiroki Takagi
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | - Akira Abe
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | - Takao Yokota
- Department of Biosciences, Teikyo University, Utsunomiya, Tochigi, 320-8551, Japan
| | | | - Haruko Okamoto
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Iwate Medical University, Iwate, 028-3694, Japan
| | | | | | - Koki Fujisaki
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | - Kaori Oikawa
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | - Aiko Uemura
- Iwate Biotechnology Research Center, Iwate, 024-003, Japan
| | | | - Yusuke Jikumaru
- Department of Biosciences, Teikyo University, Utsunomiya, Tochigi, 320-8551, Japan
| | - Hideyuki Matsuura
- Division of Applied Bioscience, Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Kenji Umemura
- Agricultural and Veterinary Research Laboratories, Meiji Seika Pharma Co., Ltd, Kohoku-ku, Yokohama, 222-8567, Japan
| | - Matthew J Terry
- Centre for Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
- Institute for Life Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
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Kashiwakura YI, Kobayashi D, Jikumaru Y, Takebayashi Y, Nambara E, Seo M, Kamiya Y, Kushiro T, Kawakami N. Highly Sprouting-Tolerant Wheat Grain Exhibits Extreme Dormancy and Cold Imbibition-Resistant Accumulation of Abscisic Acid. Plant Cell Physiol 2016; 57:715-32. [PMID: 26971301 DOI: 10.1093/pcp/pcw051] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 03/07/2016] [Indexed: 05/21/2023]
Abstract
Pre-harvest sprouting (PHS) of wheat (Triticum aestivum L.) grains induces hydrolyzing enzymes such as α-amylase, which considerably decreases wheat product quality. PHS occurs when cool and wet weather conditions before harvest break dormancy and induce grain germination. In this study, we used PHS-tolerant varieties, Gifu-komugi (Gifu) and OS38, to characterize the mechanisms of both dormancy breakage and dormancy maintenance at low temperatures. Physiologically mature Gifu grains exhibited dormancy after imbibition at 20°C, but germinated at 15°C. In contrast, OS38 grains remained dormant even at temperatures as low as 5°C. Embryo half-grains cut out from the dormant Gifu grains germinated by imbibition at 20°C, similar to conventional varieties worldwide. However, OS38 embryo half-grains were still dormant. Hormonome and pharmacological analyses suggested that ABA and gibberellin metabolism are important for temperature-dependent dormancy maintenance and breakage. Imbibition at 15°C decreased ABA levels but increased gibberellin levels in embryos of freshly harvested Gifu grains. Additionally, low temperatures induced expression of the ABA catabolism genes,TaABA8' OH1 and TaABA8' OH2, and the gibberellin biosynthesis gene,TaGA3ox2, in the embryos. However, in embryos of freshly harvested OS38 grains, ABA levels were increased while gibberellin levels were suppressed at 15°C. In these dormant embryos, low temperatures induced the TaNCED ABA biosynthesis genes, but suppressed TaABA8' OH2 and TaGA3ox2.These results show that the regulatory mechanism influencing the expression of ABA and gibberellin metabolism genes may be critical for dormancy maintenance and breakage at low temperatures. Our findings should help improve PHS-resistant wheat breeding programs.
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Affiliation(s)
- Yu-ichi Kashiwakura
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, 214-8571 Japan Present address: Central Research Laboratory, Nitto Fuji Milling Co., Ltd., 6-2-1 Tokai, Ohta-ku, Tokyo, 143-0001 Japan. These authors contributed equally to this work
| | - Daisuke Kobayashi
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, 214-8571 Japan These authors contributed equally to this work
| | - Yusuke Jikumaru
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan Present address: Agilent Technologies Japan, Ltd., 9-1, Takakura-machi, Hachioji-shi, Tokyo, 192-8510 Japan
| | - Yumiko Takebayashi
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan
| | - Eiji Nambara
- Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Mitsunori Seo
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan
| | - Yuji Kamiya
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan
| | - Tetsuo Kushiro
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, 214-8571 Japan
| | - Naoto Kawakami
- Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, 214-8571 Japan
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Miyazaki Y, Jikumaru Y, Takase T, Saitoh A, Sugitani A, Kamiya Y, Kiyosue T. Enhancement of hypocotyl elongation by LOV KELCH PROTEIN2 production is mediated by auxin and phytochrome-interacting factors in Arabidopsis thaliana. Plant Cell Rep 2016; 35:455-467. [PMID: 26601822 DOI: 10.1007/s00299-015-1896-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 10/12/2015] [Accepted: 11/03/2015] [Indexed: 06/05/2023]
Abstract
Auxin and two phytochrome-interacting factors, PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5, play crucial roles in the enhancement of hypocotyl elongation in transgenic Arabidopsis thaliana plants that overproduce LOV KELCH PROTEIN2 (LKP2). LOV KELCH PROTEIN2 (LKP2) is a positive regulator of hypocotyl elongation under white light in Arabidopsis thaliana. In this study, using microarray analysis, we compared the gene expression profiles of hypocotyls of wild-type Arabidopsis (Columbia accession), a transgenic line that produces green fluorescent protein (GFP), and two lines that produce GFP-tagged LKP2 (GFP-LKP2). We found that, in GFP-LKP2 hypocotyls, 775 genes were up-regulated, including 36 auxin-responsive genes, such as 27 SMALL AUXIN UP RNA (SAUR) and 6 AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) genes, and 21 genes involved in responses to red or far-red light, including PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5; and 725 genes were down-regulated, including 15 flavonoid biosynthesis genes. Hypocotyls of GFP-LKP2 seedlings, but not cotyledons or roots, contained a higher level of indole-3-acetic acid (IAA) than those of control seedlings. Auxin inhibitors reduced the enhancement of hypocotyl elongation in GFP-LKP2 seedlings by inhibiting the increase in cortical cell number and elongation of the epidermal and cortical cells. The enhancement of hypocotyl elongation was completely suppressed in progeny of the crosses between GFP-LKP2 lines and dominant gain-of-function auxin-resistant mutants (axr2-1 and axr3-1) or loss-of-function mutants pif4, pif5, and pif4 pif5. Our results suggest that the enhancement of hypocotyl elongation in GFP-LKP2 seedlings is due to the elevated level of IAA and to the up-regulated expression of PIF4 and PIF5 in hypocotyls.
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Affiliation(s)
- Yuji Miyazaki
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-Ku, Tokyo, 171-8588, Japan
| | - Yusuke Jikumaru
- Growth Regulation Research Group, RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan
| | - Tomoyuki Takase
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-Ku, Tokyo, 171-8588, Japan
| | - Aya Saitoh
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-Ku, Tokyo, 171-8588, Japan
| | - Asuka Sugitani
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-Ku, Tokyo, 171-8588, Japan
| | - Yuji Kamiya
- Growth Regulation Research Group, RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan
| | - Tomohiro Kiyosue
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-Ku, Tokyo, 171-8588, Japan.
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Wei HH, Rowe M, Riethoven JJM, Grove R, Adamec J, Jikumaru Y, Staswick P. Overaccumulation of γ-Glutamylcysteine in a Jasmonate-Hypersensitive Arabidopsis Mutant Causes Jasmonate-Dependent Growth Inhibition. Plant Physiol 2015; 169:1371-81. [PMID: 26282239 PMCID: PMC4587470 DOI: 10.1104/pp.15.00999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 08/14/2015] [Indexed: 05/08/2023]
Abstract
Glutathione (GSH) is essential for many aspects of plant biology and is associated with jasmonate signaling in stress responses. We characterized an Arabidopsis (Arabidopsis thaliana) jasmonate-hypersensitive mutant (jah2) with seedling root growth 100-fold more sensitive to inhibition by the hormone jasmonyl-isoleucine than the wild type. Genetic mapping and genome sequencing determined that the mutation is in intron 6 of GLUTATHIONE SYNTHETASE2, encoding the enzyme that converts γ-glutamylcysteine (γ-EC) to GSH. The level of GSH in jah2 was 71% of the wild type, while the phytoalexin-deficient2-1 (pad2-1) mutant, defective in GSH1 and having only 27% of wild-type GSH level, was not jasmonate hypersensitive. Growth defects for jah2, but not pad2, were also seen in plants grown to maturity. Surprisingly, all phenotypes in the jah2 pad2-1 double mutant were weaker than in jah2. Quantification of γ-EC indicated these defects result from hyperaccumulation of this GSH precursor by 294- and 65-fold in jah2 and the double mutant, respectively. γ-EC reportedly partially substitutes for loss of GSH, but growth inhibition seen here was likely not due to an excess of total glutathione plus γ-EC because their sum in jah2 pad2-1 was only 16% greater than in the wild type. Further, the jah2 phenotypes were lost in a jasmonic acid biosynthesis mutant background, indicating the effect of γ-EC is mediated through jasmonate signaling and not as a direct result of perturbed redox status.
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Affiliation(s)
- Hsin-Ho Wei
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Martha Rowe
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Jean-Jack M Riethoven
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Ryan Grove
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Jiri Adamec
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Yusuke Jikumaru
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
| | - Paul Staswick
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68583 (H.-H.W., M.R., P.S.);Center for Biotechnology (J.-J.M.R.), and Department of Biochemistry (R.G., J.A.), University of Nebraska, Lincoln, Nebraska 68588; andRiken Plant Science Center, Yokohama 230-0045, Japan (Y.J.)
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Wu S, Clevenger JP, Sun L, Visa S, Kamiya Y, Jikumaru Y, Blakeslee J, van der Knaap E. The control of tomato fruit elongation orchestrated by sun, ovate and fs8.1 in a wild relative of tomato. Plant Sci 2015; 238:95-104. [PMID: 26259178 DOI: 10.1016/j.plantsci.2015.05.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 05/24/2015] [Accepted: 05/28/2015] [Indexed: 05/23/2023]
Abstract
Within the cultivated tomato germplasm, sun, ovate and fs8.1 are the three predominant QTLs controlling fruit elongation. Although SUN and OVATE have been cloned, their role in plant growth and development are not well understood. To compare and contrast the effects of the three QTLs in a homogeneous background, we developed near isogenic lines (NILs) in the wild species Solanum pimpinellifolium LA1589 background. We carried out detailed morphological characterization of reproductive and vegetative organs in the single, double and triple NILs and determined the epistatic interactions of the three loci affecting fruit shape. The phenotypic evaluations demonstrated that the three loci regulate unique aspects of ovary and fruit elongation and in different temporal manners. The strongest effect on organ shape was caused by sun. In addition to fruit shape, sun also affected leaf and sepal elongation and stem thickness. The synergistic interaction between sun and ovate or fs8.1 suggested that the pathways involving SUN, OVATE and the gene(s) underlying fs8.1 may converge at a common node. The results of an extensive profiling analysis suggested that the degree of fruit elongation was not related to the accumulation of any of the classical hormones.
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Affiliation(s)
- Shan Wu
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH 44691, USA
| | - Josh P Clevenger
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH 44691, USA
| | - Liang Sun
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH 44691, USA
| | - Sofia Visa
- Department of Mathematics and Computer Science, The College of Wooster, Wooster, OH 44691, USA
| | - Yuji Kamiya
- RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yusuke Jikumaru
- RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Joshua Blakeslee
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH 44691, USA
| | - Esther van der Knaap
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH 44691, USA.
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10
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Oikawa A, Otsuka T, Nakabayashi R, Jikumaru Y, Isuzugawa K, Murayama H, Saito K, Shiratake K. Metabolic Profiling of Developing Pear Fruits Reveals Dynamic Variation in Primary and Secondary Metabolites, Including Plant Hormones. PLoS One 2015; 10:e0131408. [PMID: 26168247 PMCID: PMC4500446 DOI: 10.1371/journal.pone.0131408] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 06/02/2015] [Indexed: 02/08/2023] Open
Abstract
Metabolites in the fruits of edible plants include sweet sugars, visually appealing pigments, various products with human nutritional value, and biologically active plant hormones. Although quantities of these metabolites vary during fruit development and ripening because of cell division and enlargement, there are few reports describing the actual dynamics of these changes. Therefore, we applied multiple metabolomic techniques to identify the changes in metabolite levels during the development and ripening of pear fruits (Pyrus communis L. ‘La France’). We quantified and classified over 250 metabolites into six groups depending on their specific patterns of variation during development and ripening. Approximately half the total number of metabolites, including histidine and malate, accumulated transiently around the blooming period, during which cells are actively dividing, and then decreased either rapidly or slowly. Furthermore, the amounts of sulfur-containing amino acids also increased in pear fruits around 3–4 months after the blooming period, when fruit cells are enlarging, but virtually disappeared from ripened fruits. Some metabolites, including the plant hormone abscisic acid, accumulated particularly in the receptacle prior to blooming and/or fruit ripening. Our results show several patterns of variation in metabolite levels in developing and ripening pear fruits, and provide fundamental metabolomic data that is useful for understanding pear fruit physiology and enhancing the nutritional traits of new cultivars.
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Affiliation(s)
- Akira Oikawa
- RIKEN Center for Sustainable Resource Science, Yokohama, 230–0045, Japan
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997–8555, Japan
- * E-mail:
| | - Takao Otsuka
- RIKEN Center for Sustainable Resource Science, Yokohama, 230–0045, Japan
| | - Ryo Nakabayashi
- RIKEN Center for Sustainable Resource Science, Yokohama, 230–0045, Japan
| | - Yusuke Jikumaru
- RIKEN Center for Sustainable Resource Science, Yokohama, 230–0045, Japan
| | - Kanji Isuzugawa
- Yamagata Integrated Agricultural Research Center, Sagae, 999–7601, Japan
| | - Hideki Murayama
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997–8555, Japan
| | - Kazuki Saito
- RIKEN Center for Sustainable Resource Science, Yokohama, 230–0045, Japan
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260–8675, Japan
| | - Katsuhiro Shiratake
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464–8601, Japan
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11
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Clevenger JP, Van Houten J, Blackwood M, Rodríguez GR, Jikumaru Y, Kamiya Y, Kusano M, Saito K, Visa S, van der Knaap E. Network Analyses Reveal Shifts in Transcript Profiles and Metabolites That Accompany the Expression of SUN and an Elongated Tomato Fruit. Plant Physiol 2015; 168:1164-78. [PMID: 25941316 PMCID: PMC4741315 DOI: 10.1104/pp.15.00379] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/04/2015] [Indexed: 05/04/2023]
Abstract
SUN controls elongated tomato (Solanum lycopersicum) shape early in fruit development through changes in cell number along the different axes of growth. The gene encodes a member of the IQ domain family characterized by a calmodulin binding motif. To gain insights into the role of SUN in regulating organ shape, we characterized genome-wide transcriptional changes and metabolite and hormone accumulation after pollination and fertilization in wild-type and SUN fruit tissues. Pericarp, seed/placenta, and columella tissues were collected at 4, 7, and 10 d post anthesis. Pairwise comparisons between SUN and the wild type identified 3,154 significant differentially expressed genes that cluster in distinct gene regulatory networks. Gene regulatory networks that were enriched for cell division, calcium/transport, lipid/hormone, cell wall, secondary metabolism, and patterning processes contributed to profound shifts in gene expression in the different fruit tissues as a consequence of high expression of SUN. Promoter motif searches identified putative cis-elements recognized by known transcription factors and motifs related to mitotic-specific activator sequences. Hormone levels did not change dramatically, but some metabolite levels were significantly altered, namely participants in glycolysis and the tricarboxylic acid cycle. Also, hormone and primary metabolite networks shifted in SUN compared with wild-type fruit. Our findings imply that SUN indirectly leads to changes in gene expression, most strongly those involved in cell division, cell wall, and patterning-related processes. When evaluating global coregulation in SUN fruit, the main node represented genes involved in calcium-regulated processes, suggesting that SUN and its calmodulin binding domain impact fruit shape through calcium signaling.
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Affiliation(s)
- Josh P Clevenger
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Jason Van Houten
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Michelle Blackwood
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Gustavo Rubén Rodríguez
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Yusuke Jikumaru
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Yuji Kamiya
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Miyako Kusano
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Kazuki Saito
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Sofia Visa
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
| | - Esther van der Knaap
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691 (J.P.C., J.V.H., G.R.R., E.v.d.K.);Department of Mathematics and Computer Science, The College of Wooster, Wooster, Ohio 44691 (M.B., S.V.);RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan (Y.J., Y.K., M.K., K.S.); andDepartment of Molecular Biology and Biotechnology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan (K.S.)
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12
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Acheampong AK, Hu J, Rotman A, Zheng C, Halaly T, Takebayashi Y, Jikumaru Y, Kamiya Y, Lichter A, Sun TP, Or E. Functional characterization and developmental expression profiling of gibberellin signalling components in Vitis vinifera. J Exp Bot 2015; 66:1463-76. [PMID: 25588745 PMCID: PMC4339604 DOI: 10.1093/jxb/eru504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Gibberellins (GAs) regulate numerous developmental processes in grapevine (Vitis vinifera) such as rachis elongation, fruit set, and fruitlet abscission. The ability of GA to promote berry enlargement has led to its indispensable use in the sternospermocarpic ('seedless') table grape industry worldwide. However, apart from VvGAI1 (VvDELLA1), which regulates internode elongation and fruitfulness, but not berry size of seeded cultivars, little was known about GA signalling in grapevine. We have identified and characterized two additional DELLAs (VvDELLA2 and VvDELLA3), two GA receptors (VvGID1a and VvGID1b), and two GA-specific F-box proteins (VvSLY1a and VvSLY1b), in cv. Thompson seedless. With the exception of VvDELLA3-VvGID1b, all VvDELLAs interacted with the VvGID1s in a GA-dependent manner in yeast two-hybrid assays. Additionally, expression of these grape genes in corresponding Arabidopsis mutants confirmed their functions in planta. Spatiotemporal analysis of VvDELLAs showed that both VvDELLA1 and VvDELLA2 are abundant in most tissues, except in developing fruit where VvDELLA2 is uniquely expressed at high levels, suggesting a key role in fruit development. Our results further suggest that differential organ responses to exogenous GA depend on the levels of VvDELLA proteins and endogenous bioactive GAs. Understanding this interaction will allow better manipulation of GA signalling in grapevine.
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Affiliation(s)
- Atiako Kwame Acheampong
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Jianhong Hu
- Department of Biology, Duke University, Durham, North Carolina 27708, USA
| | - Ariel Rotman
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel
| | - Chuanlin Zheng
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Tamar Halaly
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel
| | | | - Yusuke Jikumaru
- RIKEN Plant Science Centre, Yokohama, Kanagawa 230-0045, Japan
| | - Yuji Kamiya
- RIKEN Plant Science Centre, Yokohama, Kanagawa 230-0045, Japan
| | - Amnon Lichter
- Institute of Postharvest and Food Sciences, Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel
| | - Tai-Ping Sun
- Department of Biology, Duke University, Durham, North Carolina 27708, USA
| | - Etti Or
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel
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13
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Zheng C, Halaly T, Acheampong AK, Takebayashi Y, Jikumaru Y, Kamiya Y, Or E. Abscisic acid (ABA) regulates grape bud dormancy, and dormancy release stimuli may act through modification of ABA metabolism. J Exp Bot 2015; 66:1527-42. [PMID: 25560179 PMCID: PMC4339608 DOI: 10.1093/jxb/eru519] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
In warm-winter regions, induction of dormancy release by hydrogen cyanamide (HC) is mandatory for commercial table grape production. Induction of respiratory stress by HC leads to dormancy release via an uncharacterized biochemical cascade that could reveal the mechanism underlying this phenomenon. Previous studies proposed a central role for abscisic acid (ABA) in the repression of bud meristem activity, and suggested its removal as a critical step in the HC-induced cascade. In the current study, support for these assumptions was sought. The data show that ABA indeed inhibits dormancy release in grape (Vitis vinifera) buds and attenuates the advancing effect of HC. However, HC-dependent recovery was detected, and was affected by dormancy status. HC reduced VvXERICO and VvNCED transcript levels and induced levels of VvABA8'OH homologues. Regulation of these central players in ABA metabolism correlated with decreased ABA and increased ABA catabolite levels in HC-treated buds. Interestingly, an inhibitor of ethylene signalling attenuated these effects of HC on ABA metabolism. HC also modulated the expression of ABA signalling regulators, in a manner that supports a decreased ABA level and response. Taken together, the data support HC-induced removal of ABA-mediated repression via regulation of ABA metabolism and signalling. Expression profiling during the natural dormancy cycle revealed that at maximal dormancy, the HC-regulated VvNCED1 transcript level starts to drop. In parallel, levels of VvA8H-CYP707A4 transcript and ABA catabolites increase sharply. This may provide initial support for the involvement of ABA metabolism also in the execution of natural dormancy.
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Affiliation(s)
- Chuanlin Zheng
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Tamar Halaly
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
| | - Atiako Kwame Acheampong
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | | | - Yusuke Jikumaru
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | - Yuji Kamiya
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | - Etti Or
- Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
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14
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Mochizuki S, Jikumaru Y, Nakamura H, Koiwai H, Sasaki K, Kamiya Y, Ichikawa H, Minami E, Nishizawa Y. Ubiquitin ligase EL5 maintains the viability of root meristems by influencing cytokinin-mediated nitrogen effects in rice. J Exp Bot 2014; 65:2307-18. [PMID: 24663342 PMCID: PMC4036501 DOI: 10.1093/jxb/eru110] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Root formation is dependent on meristematic activity and is influenced by nitrogen supply. We have previously shown that ubiquitin ligase, EL5, in rice (Oryza sativa) is involved in the maintenance of root meristematic viability. When mutant EL5 protein is overexpressed to dominantly inhibit the endogenous EL5 function in rice, primordial and meristematic necrosis ia observed. Here, we analysed the cause of root cell death in transgenic rice plants (mEL5) overexpressing EL5V162A, which encodes a partly inactive ubiquitin ligase. The mEL5 mutants showed increased sensitivity to nitrogen that was reflected in the inhibition of root formation. Treatment of mEL5 with nitrate or nitrite caused meristematic cell death accompanied by browning. Transcriptome profiling of whole roots exhibited overlaps between nitrite-responsive genes in non-transgenic (NT) rice plants and genes with altered basal expression levels in mEL5. Phytohormone profiling of whole roots revealed that nitrite treatment increased cytokinin levels, but mEL5 constitutively contained more cytokinin than NT plants and showed increased sensitivity to exogenous cytokinin. More superoxide was detected in mEL5 roots after treatment with nitrite or cytokinin, and treatment with an inhibitor of superoxide production prevented mEL5 roots from both nitrite- and cytokinin-induced meristematic cell death. These results indicate a nitrogen-triggered pathway that leads to changes in root formation through the production of cytokinin and superoxide, on which EL5 acts to prevent meristematic cell death.
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Affiliation(s)
- Susumu Mochizuki
- Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | - Yusuke Jikumaru
- Growth Regulation Research Group, RIKEN Plant Science Center, Suehiro-cho 1-7-22, Tsurumi, Yokohama, Kanagawa, 230-0045 Japan
| | - Hidemitsu Nakamura
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | - Hanae Koiwai
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | - Keisuke Sasaki
- National Institute of Livestock and Grassland Science, Ikenodai 2, Tsukuba, Ibaraki, 305-0901 Japan
| | - Yuji Kamiya
- Growth Regulation Research Group, RIKEN Plant Science Center, Suehiro-cho 1-7-22, Tsurumi, Yokohama, Kanagawa, 230-0045 Japan
| | - Hiroaki Ichikawa
- Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | - Eiichi Minami
- Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan
| | - Yoko Nishizawa
- Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan Growth Regulation Research Group, RIKEN Plant Science Center, Suehiro-cho 1-7-22, Tsurumi, Yokohama, Kanagawa, 230-0045 Japan Division of Plant Sciences, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602 Japan National Institute of Livestock and Grassland Science, Ikenodai 2, Tsukuba, Ibaraki, 305-0901 Japan
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15
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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. J Exp Bot 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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Tamiru M, Abe A, Utsushi H, Yoshida K, Takagi H, Fujisaki K, Undan JR, Rakshit S, Takaichi S, Jikumaru Y, Yokota T, Terry MJ, Terauchi R. The tillering phenotype of the rice plastid terminal oxidase (PTOX) loss-of-function mutant is associated with strigolactone deficiency. New Phytol 2014; 202:116-131. [PMID: 24350905 DOI: 10.1111/nph.12630] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/07/2013] [Indexed: 06/03/2023]
Abstract
The significance of plastid terminal oxidase (PTOX) in phytoene desaturation and chloroplast function has been demonstrated using PTOX-deficient mutants, particularly in Arabidopsis. However, studies on its role in monocots are lacking. Here, we report cloning and characterization of the rice (Oryza sativa) PTOX1 gene. Using Ecotype Targeting Induced Local Lesions IN Genomes (EcoTILLING) and TILLING as forward genetic tools, we identified the causative mutation of an EMS mutant characterized by excessive tillering, semi-dwarfism and leaf variegation that corresponded to the PTOX1 gene. The tillering and semi-dwarf phenotypes of the ptox1 mutant are similar to phenotypes of known strigolactone (SL)-related rice mutants, and both phenotypic traits could be rescued by application of the synthetic SL GR24. The ptox1 mutant accumulated phytoene in white leaf sectors with a corresponding deficiency in β-carotene, consistent with the expected function of PTOX1 in promoting phytoene desaturase activity. There was also no accumulation of the carotenoid-derived SL ent-2'-epi-5-deoxystrigol in root exudates. Elevated concentrations of auxin were detected in the mutant, supporting previous observations that SL interaction with auxin is important in shoot branching control. Our results demonstrate that PTOX1 is required for both carotenoid and SL synthesis resulting in SL-deficient phenotypes in rice.
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Affiliation(s)
- Muluneh Tamiru
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
| | - Akira Abe
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
- Iwate Agricultural Research Center, Narita 20-1, Kitakami, Iwate, 024-0003, Japan
| | - Hiroe Utsushi
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
| | - Kakoto Yoshida
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
| | - Hiroki Takagi
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Koki Fujisaki
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
| | - Jerwin R Undan
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Sujay Rakshit
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
| | - Shinichi Takaichi
- Department of Biology, Nippon Medical School, Kawasaki, Kanagawa, 211-0063, Japan
| | - Yusuke Jikumaru
- Department of Biosciences, Faculty of Science and Technology, Teikyo University, Utsunomiya, Tochigi, 320-8851, Japan
| | - Takao Yokota
- Department of Biosciences, Faculty of Science and Technology, Teikyo University, Utsunomiya, Tochigi, 320-8851, Japan
| | - Matthew J Terry
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
- Centre for Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Ryohei Terauchi
- Iwate Biotechnology Research Center, Narita 22-174-4, Kitakami, Iwate, 024-0003, Japan
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17
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Svyatyna K, Jikumaru Y, Brendel R, Reichelt M, Mithöfer A, Takano M, Kamiya Y, Nick P, Riemann M. Light induces jasmonate-isoleucine conjugation via OsJAR1-dependent and -independent pathways in rice. Plant Cell Environ 2014; 37:827-39. [PMID: 24033451 DOI: 10.1111/pce.12201] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 08/26/2013] [Accepted: 09/04/2013] [Indexed: 05/22/2023]
Abstract
The bioactive form of jasmonate is the conjugate of the amino acid isoleucine (Ile) with jasmonic acid (JA), which is biosynthesized in a reaction catalysed by the GH3 enzyme JASMONATE RESISTANT 1 (JAR1). We examined the biochemical properties of OsJAR1 and its involvement in photomorphogenesis of rice (Oryza sativa). OsJAR1 has a similar substrate specificities as its orthologue in Arabidopsis. However, osjar1 loss-of-function mutants did not show as severe coleoptile phenotypes as the JA-deficient mutants coleoptile photomorphogenesis 2 (cpm2) and hebiba, which develop long coleoptiles in all light qualities we examined. Analysis of hormonal contents in the young seedling stage revealed that osjar1 mutants are still able to synthesize JA-Ile conjugate in response to blue light, suggesting that a redundantly active enzyme can conjugate JA and Ile in rice seedlings. A good candidate for this enzyme is OsJAR2, which was found to be able to catalyse the conjugation of JA with Ile as well as with some additional amino acids. In contrast, if plants in the vegetative stage were mechanically wounded, the content of JA-Ile was severely reduced in osjar1, demonstrating that OsJAR1 is the most important JA-Ile conjugating enzyme in the wounding response during the vegetative stage.
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Affiliation(s)
- Katharina Svyatyna
- Botanical Institute, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany
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18
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Brendel R, Svyatyna K, Jikumaru Y, Reichelt M, Mithöfer A, Takano M, Kamiya Y, Nick P, Riemann M. Effects of Light and Wounding on Jasmonates in Rice phyAphyC Mutants. Plants (Basel) 2014; 3:143-59. [PMID: 27135497 PMCID: PMC4844304 DOI: 10.3390/plants3010143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 02/18/2014] [Accepted: 02/24/2014] [Indexed: 11/26/2022]
Abstract
Jasmonates (JA) are lipid-derived plant hormones. They have been shown to be important regulators of photomorphogenesis, a developmental program in plants, which is activated by light through different red and blue light sensitive photoreceptors. In rice, inhibition of coleoptile growth by light is a central event in photomorphogenesis. This growth inhibition is impaired, when jasmonate biosynthesis is knocked out. Previously, we found that JASMONATE RESISTANT 1 (OsJAR1) transcripts were not induced in the phytochrome (phy) mutant phyAphyC. Therefore, in the current study we investigated the regulation of JA and its highly bioactive derivative (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), as well as the transcriptional regulation of several JA-dependent genes both in wild type and phyAphyC mutant. JA and JA-Ile levels increased in the mutant seedlings in response to blue light. However, in phyAphyC mutant leaves, which were continuously wounded, JA and JA-Ile levels were lower compared to those in the wild type. Hence, the mutation of phyA and phyC has differential effects on jasmonate levels depending on the tissue and developmental stage. Our results suggest that the contribution of JA-Ile to signaling during photomorphogenesis of rice is minor, as coleoptile phenotypes of phyAphyC mutants resemble those of jasmonate-deficient mutants despite the fact that induction by blue light leads to higher levels of JA-Ile compared to the wild type. We postulate that phyA and phyC could control the activity of specific enzymes metabolizing JA to active derivatives.
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Affiliation(s)
- Rita Brendel
- Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany.
| | - Katharina Svyatyna
- Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany.
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany.
| | - Axel Mithöfer
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany.
| | - Makoto Takano
- Department of Plant Physiology, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
| | - Yuji Kamiya
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
| | - Peter Nick
- Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany.
| | - Michael Riemann
- Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany.
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Gallego-Giraldo L, Bhattarai K, Pislariu CI, Nakashima J, Jikumaru Y, Kamiya Y, Udvardi MK, Monteros MJ, Dixon RA. Lignin modification leads to increased nodule numbers in alfalfa. Plant Physiol 2014; 164:1139-50. [PMID: 24406794 PMCID: PMC3938609 DOI: 10.1104/pp.113.232421] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 01/08/2014] [Indexed: 05/11/2023]
Abstract
Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials.
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Affiliation(s)
| | - Kishor Bhattarai
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Catalina I. Pislariu
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Jin Nakashima
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Yusuke Jikumaru
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Yuji Kamiya
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Michael K. Udvardi
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
| | - Maria J. Monteros
- Plant Biology Division (L.G.-G., C.I.P., J.N., M.K.U., R.A.D.) and Forage Improvement Division (K.B., M.J.M.), Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401; and
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan (Y.J., Y.K.)
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20
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Hu Z, Yamauchi T, Yang J, Jikumaru Y, Tsuchida-Mayama T, Ichikawa H, Takamure I, Nagamura Y, Tsutsumi N, Yamaguchi S, Kyozuka J, Nakazono M. Strigolactone and cytokinin act antagonistically in regulating rice mesocotyl elongation in darkness. Plant Cell Physiol 2014; 55:30-41. [PMID: 24151204 DOI: 10.1093/pcp/pct150] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Strigolactones (SLs) are a group of phytohormones that control plant growth and development including shoot branching. Previous studies of the phenotypes of SL-related rice (Oryza sativa) dwarf (d) mutants demonstrated that SLs inhibit mesocotyl elongation by controlling cell division. Here, we found that the expression of cytokinin (CK)-responsive type-A RESPONSE REGULATOR (RR) genes was higher in d10-1 and d14-1 mutants than in the wild type. However, CK levels in mesocotyls of the d mutants were not very different from those in the wild type. On the other hand, application of a synthetic CK (kinetin) enhanced mesocotyl elongation in the d mutants and the wild type. d10-1 and d14-1 mesocotyls were more sensitive to CK than wild-type mesocotyls, suggesting that the up-regulation of the CK-responsive type-A RR genes and the higher elongation of mesocotyls in the d mutants are mainly due to the increased sensitivity of the d mutants to CK. Co-treatment with kinetin and a synthetic SL (GR24) confirmed the antagonistic functions of SL and CK on mesocotyl elongation. OsTCP5, which encodes a transcription factor belonging to the cell division-regulating TCP family, was also regulated by SL and CK and its expression was negatively correlated with mesocotyl length. These findings suggest that OsTCP5 contributes to the SL- and CK-controlled mesocotyl elongation in darkness.
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Affiliation(s)
- Zhongyuan Hu
- Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8657 Japan
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21
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Otani M, Meguro S, Gondaira H, Hayashi M, Saito M, Han DS, Inthima P, Supaibulwatana K, Mori S, Jikumaru Y, Kamiya Y, Li T, Niki T, Nishijima T, Koshioka M, Nakano M. Overexpression of the gibberellin 2-oxidase gene from Torenia fournieri induces dwarf phenotypes in the liliaceous monocotyledon Tricyrtis sp. J Plant Physiol 2013; 170:1416-23. [PMID: 23747060 DOI: 10.1016/j.jplph.2013.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 05/09/2013] [Accepted: 05/09/2013] [Indexed: 05/09/2023]
Abstract
Gibberellins (GAs) are the plant hormones that control many aspects of plant growth and development, including stem elongation. Genes encoding enzymes related to the GA biosynthetic and metabolic pathway have been isolated and characterized in many plant species. Gibberellin 2-oxidase (GA2ox) catalyzes bioactive GAs or their immediate precursors to inactive forms; therefore, playing a direct role in determining the levels of bioactive GAs. In the present study, we produced transgenic plants of the liliaceous monocotyledon Tricyrtis sp. overexpressing the GA2ox gene from the linderniaceous dicotyledon Torenia fournieri (TfGA2ox2). All six transgenic plants exhibited dwarf phenotypes, and they could be classified into two classes according to the degree of dwarfism: three plants were moderately dwarf and three were severely dwarf. All of the transgenic plants had small or no flowers, and smaller, rounder and darker green leaves. Quantitative real-time reverse transcription-polymerase chain reaction (PCR) analysis showed that the TfGA2ox2 expression level generally correlated with the degree of dwarfism. The endogenous levels of bioactive GAs, GA1 and GA4, largely decreased in transgenic plants as shown by liquid chromatography-mass spectrometry (LC-MS) analysis, and the level also correlated with the degree of dwarfism. Exogenous treatment of transgenic plants with gibberellic acid (GA3) resulted in an increased shoot length, indicating that the GA signaling pathway might normally function in transgenic plants. Thus, morphological changes in transgenic plants may result from a decrease in the endogenous levels of bioactive GAs. Finally, a possibility of molecular breeding for plant form alteration in liliaceous ornamental plants by genetically engineering the GA metabolic pathway is discussed.
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Affiliation(s)
- Masahiro Otani
- Faculty of Agriculture, Niigata University, 2-8050 Ikarashi, Niigata 950-2181, Japan
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22
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Abstract
The endogenous concentration of N-jasmonoyl-L-isoleucine (JA-Ile) is regulated by the balance between biosynthesis and deactivation and controls plant developmental processes and stress responses. Therefore, profiling of its precursors and metabolites is required to understand the mechanism by which the JA-Ile concentration is regulated. Also, other hormones, such as indole-3-acetic acid, abscisic acid, salicylic acid, and ethylene, have been suggested to interact with JA-Ile signaling. Profiling of these hormones and their metabolites should give us insights into their interaction mode. Liquid chromatography-electrospray ionization-tandem mass spectrometry has enabled us to develop a highly sensitive and high-throughput comprehensive quantification analysis of phytohormones.
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23
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Sarnowska EA, Rolicka AT, Bucior E, Cwiek P, Tohge T, Fernie AR, Jikumaru Y, Kamiya Y, Franzen R, Schmelzer E, Porri A, Sacharowski S, Gratkowska DM, Zugaj DL, Taff A, Zalewska A, Archacki R, Davis SJ, Coupland G, Koncz C, Jerzmanowski A, Sarnowski TJ. DELLA-interacting SWI3C core subunit of switch/sucrose nonfermenting chromatin remodeling complex modulates gibberellin responses and hormonal cross talk in Arabidopsis. Plant Physiol 2013; 163:305-17. [PMID: 23893173 PMCID: PMC3762652 DOI: 10.1104/pp.113.223933] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/17/2013] [Indexed: 05/18/2023]
Abstract
Switch (SWI)/Sucrose Nonfermenting (SNF)-type chromatin-remodeling complexes (CRCs) are involved in regulation of transcription, DNA replication and repair, and cell cycle. Mutations of conserved subunits of plant CRCs severely impair growth and development; however, the underlying causes of these phenotypes are largely unknown. Here, we show that inactivation of SWI3C, the core component of Arabidopsis (Arabidopsis thaliana) SWI/SNF CRCs, interferes with normal functioning of several plant hormone pathways and alters transcriptional regulation of key genes of gibberellin (GA) biosynthesis. The resulting reduction of GA4 causes severe inhibition of hypocotyl and root elongation, which can be rescued by exogenous GA treatment. In addition, the swi3c mutation inhibits DELLA-dependent transcriptional activation of GIBBERELLIN-INSENSITIVE DWARF1 (GID1) GA receptor genes. Down-regulation of GID1a in parallel with the DELLA repressor gene REPRESSOR OF GA1-3 1 in swi3c indicates that lack of SWI3C also leads to defects in GA signaling. Together with the recent demonstration of function of SWI/SNF ATPase BRAHMA in the GA pathway, these results reveal a critical role of SWI/SNF CRC in the regulation of GA biosynthesis and signaling. Moreover, we demonstrate that SWI3C is capable of in vitro binding to, and shows in vivo bimolecular fluorescence complementation interaction in cell nuclei with, the DELLA proteins RGA-LIKE2 and RGA-LIKE3, which affect transcriptional activation of GID1 and GA3ox (GIBBERELLIN 3-OXIDASE) genes controlling GA perception and biosynthesis, respectively. Furthermore, we show that SWI3C also interacts with the O-GlcNAc (O-linked N-acetylglucosamine) transferase SPINDLY required for proper functioning of DELLAs and acts hypostatically to (SPINDLY) in the GA response pathway. These findings suggest that DELLA-mediated effects in GA signaling as well as their role as a hub in hormonal cross talk may be, at least in part, dependent on their direct physical interaction with complexes responsible for modulation of chromatin structure.
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Kwon Y, Kim JH, Nguyen HN, Jikumaru Y, Kamiya Y, Hong SW, Lee H. A novel Arabidopsis MYB-like transcription factor, MYBH, regulates hypocotyl elongation by enhancing auxin accumulation. J Exp Bot 2013; 64:3911-22. [PMID: 23888064 PMCID: PMC3745742 DOI: 10.1093/jxb/ert223] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Critical responses to developmental or environmental stimuli are mediated by different transcription factors, including members of the ERF, bZIP, MYB, MYC, and WRKY families. Of these, MYB genes play roles in many developmental processes. The overexpression of one MYB gene, MYBH, significantly increased hypocotyl elongation in Arabidopsis thaliana plants grown in the light, and the expression of this gene increased markedly in the dark. The MYBH protein contains a conserved motif, R/KLFGV, which was implicated in transcriptional repression. Interestingly, the gibberellin biosynthesis inhibitor paclobutrazol blocked the increase in hypocotyl elongation in seedlings that overexpressed MYBH. Moreover, the function of MYBH was dependent on phytochrome-interacting factor (PIF) proteins. Taken together, these results suggest that hypocotyl elongation is regulated by a delicate and efficient mechanism in which MYBH expression is triggered by challenging environmental conditions such as darkness, leading to an increase in PIF accumulation and subsequent enhanced auxin biosynthesis. These results indicate that MYBH is one of the molecular components that regulate hypocotyl elongation in response to darkness.
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Affiliation(s)
- Yerim Kwon
- Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, 1, 5-ka Anam-dong, Seongbuk-ku, Seoul 136-713, Republic of Korea
- *These authors contributed equally to this work
| | - Jun Hyeok Kim
- Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, 1, 5-ka Anam-dong, Seongbuk-ku, Seoul 136-713, Republic of Korea
- Institute of Life Science and Natural Resources, Korea University, Seoul 136-713, Republic of Korea
- *These authors contributed equally to this work
| | - Hoai Nguyen Nguyen
- Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, 1, 5-ka Anam-dong, Seongbuk-ku, Seoul 136-713, Republic of Korea
- Institute of Life Science and Natural Resources, Korea University, Seoul 136-713, Republic of Korea
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Yuji Kamiya
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Suk-Whan Hong
- Department of Molecular Biotechnology, College of Agriculture and Life Sciences, Bioenergy Research Institute, Chonnam National University, Gwangju, Republic of Korea
| | - Hojoung Lee
- Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, 1, 5-ka Anam-dong, Seongbuk-ku, Seoul 136-713, Republic of Korea
- To whom correspondence should be addressed.
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Sasaki-Sekimoto Y, Jikumaru Y, Obayashi T, Saito H, Masuda S, Kamiya Y, Ohta H, Shirasu K. Basic helix-loop-helix transcription factors JASMONATE-ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3 are negative regulators of jasmonate responses in Arabidopsis. Plant Physiol 2013; 163:291-304. [PMID: 23852442 PMCID: PMC3762649 DOI: 10.1104/pp.113.220129] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 07/12/2013] [Indexed: 05/18/2023]
Abstract
Jasmonates regulate transcriptional reprogramming during growth, development, and defense responses. Jasmonoyl-isoleucine, an amino acid conjugate of jasmonic acid (JA), is perceived by the protein complex composed of the F-box protein CORONATINE INSENSITIVE1 (COI1) and JASMONATE ZIM DOMAIN (JAZ) proteins, leading to the ubiquitin-dependent degradation of JAZ proteins. This activates basic helix-loop-helix-type MYC transcription factors to regulate JA-responsive genes. Here, we show that the expression of genes encoding other basic helix-loop-helix transcription factors, JASMONATE ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3, is positively regulated in a COI1- and MYC2-dependent manner in Arabidopsis (Arabidopsis thaliana). However, contrary to myc2, the jam1jam2jam3 triple mutant exhibited shorter roots when treated with methyl jasmonate (MJ), indicating enhanced responsiveness to JA. Our genome-wide expression analyses revealed that key jasmonate metabolic genes as well as a set of genes encoding transcription factors that regulate the JA-responsive metabolic genes are negatively regulated by JAMs after MJ treatment. Consistently, loss of JAM genes resulted in higher accumulation of anthocyanin in MJ-treated plants as well as higher accumulation of JA and 12-hydroxyjasmonic acid in wounded plants. These results show that JAMs negatively regulate the JA responses in a manner that is mostly antagonistic to MYC2.
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Tanaka Y, Nose T, Jikumaru Y, Kamiya Y. ABA inhibits entry into stomatal-lineage development in Arabidopsis leaves. Plant J 2013; 74:448-57. [PMID: 23373882 DOI: 10.1111/tpj.12136] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 01/17/2013] [Accepted: 01/29/2013] [Indexed: 05/03/2023]
Abstract
The number and density of stomata are controlled by endogenous and environmental factors. Despite recent advances in our understanding of stomatal development, mechanisms which prevent stomatal-lineage entry remain unclear. Here, we propose that abscisic acid (ABA), a phytohormone known to induce stomatal closure, limits initiation of stomatal development and induces enlargement of pavement cells in Arabidopsis cotyledons. An ABA-deficient aba2-2 mutant had an increased number/proportion of stomata within a smaller cotyledon, as well as reduced expansion of pavement cells. This tendency was reversed after ABA application or in an ABA over-accumulating cyp707a1cyp707a3 doublemutant. Our time course analysis revealed that aba2-2 shows prolonged formation of meristemoids and guard mother cells, both precursors of stoma. This finding is in accordance with prolonged gene expression of SPCH and MUTE, master regulators for stomatal formation, indicating that ABA acts upstream of these genes. Only aba2-2 mute, but not aba2-2 spch double mutant showed additive phenotypes and displayed inhibition of pavement cell enlargement with increased meristemoid number, indicating that ABA action on pavement cell expansion requires the presence of stomatal-lineage cells.
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Affiliation(s)
- Yoko Tanaka
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama 230-0045, Japan.
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27
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Tokuda M, Jikumaru Y, Matsukura K, Takebayashi Y, Kumashiro S, Matsumura M, Kamiya Y. Phytohormones related to host plant manipulation by a gall-inducing leafhopper. PLoS One 2013; 8:e62350. [PMID: 23638047 PMCID: PMC3640097 DOI: 10.1371/journal.pone.0062350] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 03/20/2013] [Indexed: 12/18/2022] Open
Abstract
The maize orange leafhopper Cicadulina bipunctata (Hemiptera: Cicadellidae) induces galls characterized by growth stunting and severe swelling of leaf veins on various plants of Poaceae. Previous studies revealed that galls are induced not on feeding site but on distant, newly extended leaves during the feeding, and strongly suggested that some chemicals injected by the leafhopper affect at the leaf primordia. To approach the mechanism underlying gall induction by C. bipunctata, we examined physiological response of plants to feeding by the leafhopper. We performed high-throughput and comprehensive plant hormone analyses using LC-ESI-MS/MS. Galled maize leaves contained higher contents of abscisic acid (ABA) and trans-Zeatin (tZ) and lower contents of gibberellins (GA1 and GA4) than ungalled maize leaves. Leafhopper treatment significantly increased ABA and tZ contents and decreased GA1 and GA4 contents in extending leaves. After the removal of leafhoppers, contents of tZ and gibberellins in extending leaves soon became similar to the control values. ABA content was gradually decreased after the removal of leafhoppers. Such hormonal changes were not observed in leafhopper treatment on leaves of resistant maize variety. Water contents of galled leaves were significantly lower than control leaves, suggesting water stress of galled leaves and possible reason of the increase in ABA content. These results imply that ABA, tZ, and gibberellins are related to gall induction by the leafhopper on susceptible variety of maize.
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Affiliation(s)
- Makoto Tokuda
- Laboratory of System Ecology, Faculty of Agriculture, Saga University, Saga, Japan.
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Archacki R, Buszewicz D, Sarnowski TJ, Sarnowska E, Rolicka AT, Tohge T, Fernie AR, Jikumaru Y, Kotlinski M, Iwanicka-Nowicka R, Kalisiak K, Patryn J, Halibart-Puzio J, Kamiya Y, Davis SJ, Koblowska MK, Jerzmanowski A. BRAHMA ATPase of the SWI/SNF chromatin remodeling complex acts as a positive regulator of gibberellin-mediated responses in arabidopsis. PLoS One 2013; 8:e58588. [PMID: 23536800 PMCID: PMC3594165 DOI: 10.1371/journal.pone.0058588] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Accepted: 02/05/2013] [Indexed: 11/19/2022] Open
Abstract
SWI/SNF chromatin remodeling complexes perform a pivotal function in the regulation of eukaryotic gene expression. Arabidopsis (Arabidopsis thaliana) mutants in major SWI/SNF subunits display embryo-lethal or dwarf phenotypes, indicating their critical role in molecular pathways controlling development and growth. As gibberellins (GA) are major positive regulators of plant growth, we wanted to establish whether there is a link between SWI/SNF and GA signaling in Arabidopsis. This study revealed that in brm-1 plants, depleted in SWI/SNF BRAHMA (BRM) ATPase, a number of GA-related phenotypic traits are GA-sensitive and that the loss of BRM results in markedly decreased level of endogenous bioactive GA. Transcriptional profiling of brm-1 and the GA biosynthesis mutant ga1-3, as well as the ga1-3/brm-1 double mutant demonstrated that BRM affects the expression of a large set of GA-responsive genes including genes responsible for GA biosynthesis and signaling. Furthermore, we found that BRM acts as an activator and directly associates with promoters of GA3ox1, a GA biosynthetic gene, and SCL3, implicated in positive regulation of the GA pathway. Many GA-responsive gene expression alterations in the brm-1 mutant are likely due to depleted levels of active GAs. However, the analysis of genetic interactions between BRM and the DELLA GA pathway repressors, revealed that BRM also acts on GA-responsive genes independently of its effect on GA level. Given the central position occupied by SWI/SNF complexes within regulatory networks controlling fundamental biological processes, the identification of diverse functional intersections of BRM with GA-dependent processes in this study suggests a role for SWI/SNF in facilitating crosstalk between GA-mediated regulation and other cellular pathways.
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Affiliation(s)
- Rafal Archacki
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Daniel Buszewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Tomasz J. Sarnowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Anna T. Rolicka
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Takayuki Tohge
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Alisdair R. Fernie
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Maciej Kotlinski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Roksana Iwanicka-Nowicka
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Katarzyna Kalisiak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jacek Patryn
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Joanna Halibart-Puzio
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Yuji Kamiya
- RIKEN Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Seth J. Davis
- Max-Planck Institute for Plant Breeding, Cologne, Germany
| | - Marta K. Koblowska
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Andrzej Jerzmanowski
- Department of Plant Molecular Biology, Faculty of Biology, University of Warsaw, Warsaw, Poland
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
- * E-mail:
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29
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Desaki Y, Otomo I, Kobayashi D, Jikumaru Y, Kamiya Y, Venkatesh B, Tsuyumu S, Kaku H, Shibuya N. Positive crosstalk of MAMP signaling pathways in rice cells. PLoS One 2012; 7:e51953. [PMID: 23251660 PMCID: PMC3522599 DOI: 10.1371/journal.pone.0051953] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 11/07/2012] [Indexed: 11/19/2022] Open
Abstract
Plants have evolved efficient defense mechanisms known as priming and synergy, both of which can mobilize defense responses more extensively against successive pathogen invasion or simultaneous stimulation by different signal molecules. However, the mechanisms underlying these phenomena were largely unknown. In the present study, we used cultured rice cells and combination of purified MAMP molecules as a model system to study the mechanisms of these phenomena. We found that the pretreatment of rice cells with a low concentration of bacterial lipopolysaccharide (LPS) apparently primed the defense responses induced by successive N-acetylchitooctaose (GN8) treatment. On the other hand, simultaneous treatment with GN8 and LPS also resulted in the similar enhancement of defense responses observed for the LPS-induced priming, indicating that the synergistic effects of these MAMPs are basically responsible for such enhancement of defense responses, though the effect could be interpreted as "priming" under some experimental conditions. These results also indicate that such a positive crosstalk of signaling cascade downstream of MAMP receptors seems to occur very rapidly, probably at early step(s) of signaling pathway. Comprehensive analysis of phytohormones revealed a specific enhancement of the synthesis of jasmonic acid (JA), both in the LPS pretreatment and also simultaneous treatment, indicating a role of JA in the enhancement of downstream responses.
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Affiliation(s)
- Yoshitake Desaki
- Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
| | - Ippei Otomo
- Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
| | - Daijiro Kobayashi
- Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
| | | | - Yuji Kamiya
- RIKEN Plant Science Center, Yokohama, Kanagawa, Japan
| | | | - Shinji Tsuyumu
- Faculty of Agriculture, Shizuoka University, Shizuoka, Japan
| | - Hanae Kaku
- Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
| | - Naoto Shibuya
- Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan
- * E-mail:
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30
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Schneider K, Breuer C, Kawamura A, Jikumaru Y, Hanada A, Fujioka S, Ichikawa T, Kondou Y, Matsui M, Kamiya Y, Yamaguchi S, Sugimoto K. Arabidopsis PIZZA has the capacity to acylate brassinosteroids. PLoS One 2012; 7:e46805. [PMID: 23071642 PMCID: PMC3465265 DOI: 10.1371/journal.pone.0046805] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 09/06/2012] [Indexed: 01/11/2023] Open
Abstract
Brassinosteroids (BRs) affect a wide range of developmental processes in plants and compromised production or signalling of BRs causes severe growth defects. To identify new regulators of plant organ growth, we searched the Arabidopsis FOX (Full-length cDNA Over-eXpressor gene) collection for mutants with altered organ size and isolated two overexpression lines that display typical BR deficient dwarf phenotypes. The phenotype of these lines, caused by an overexpression of a putative acyltransferase gene PIZZA (PIZ), was partly rescued by supplying exogenous brassinolide (BL) and castasterone (CS), indicating that endogenous BR levels are rate-limiting for the growth of PIZ overexpression lines. Our transcript analysis further showed that PIZ overexpression leads to an elevated expression of genes involved in BR biosynthesis and a reduced expression of BR inactivating hydroxylases, a transcriptional response typical to low BR levels. Taking the advantage of relatively high endogenous BR accumulation in a mild bri1-301 background, we found that overexpression of PIZ results in moderately reduced levels of BL and CS and a strong reduction of typhasterol (TY) and 6-deoxocastasterone (6-deoxoCS), suggesting a role of PIZ in BR metabolism. We tested a set of potential substrates in vitro for heterologously expressed PIZ and confirmed its acyltransferase activity with BL, CS and TY. The PIZ gene is expressed in various tissues but as reported for other genes involved in BR metabolism, the loss-of-function mutants did not display obvious growth phenotypes under standard growth conditions. Together, our data suggest that PIZ can modify BRs by acylation and that these properties might help modulating endogenous BR levels in Arabidopsis.
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Affiliation(s)
- Katja Schneider
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | | | - Ayako Kawamura
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | - Atsushi Hanada
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | - Shozo Fujioka
- RIKEN Advanced Science Institute, Wako, Saitama, Japan
| | | | - Youichi Kondou
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | - Minami Matsui
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | - Yuji Kamiya
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
| | | | - Keiko Sugimoto
- RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa, Japan
- * E-mail:
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31
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Noutoshi Y, Jikumaru Y, Kamiya Y, Shirasu K. ImprimatinC1, a novel plant immune-priming compound, functions as a partial agonist of salicylic acid. Sci Rep 2012; 2:705. [PMID: 23050089 PMCID: PMC3463816 DOI: 10.1038/srep00705] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 08/22/2012] [Indexed: 11/22/2022] Open
Abstract
Plant activators are agrochemicals that protect crops from pathogens. They confer durable resistance to a broad range of diseases by activating intrinsic immune mechanisms in plants. To obtain leads regarding useful compounds, we have screened a chemical library using an established method that allows selective identification of immune-priming compounds. Here, we report the characterisation of one of the isolated chemicals, imprimatinC1, and its structural derivative imprimatinC2. ImprimatinC1 functions as a weak analogue of salicylic acid (SA) and activates the expression of defence-related genes. However, it lacks antagonistic activity toward jasmonic acid. Structure-activity relationship analysis suggests that imprimatinC1 and C2 can be metabolised to 4-chlorobenzoic acid and 3,4-chlorobenzoic acid, respectively, to function in Arabidopsis. We also found that imprimatinC1 and C2 and their potential functional metabolites acted as partial agonists of SA. Thus, imprimatinC compounds could be useful tools for dissecting SA-dependent signal transduction pathways.
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Affiliation(s)
- Yoshiteru Noutoshi
- Research Core for Interdisciplinary Sciences (RCIS), Okayama University, Kita-ku, Okayama, Japan.
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32
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Noutoshi Y, Okazaki M, Kida T, Nishina Y, Morishita Y, Ogawa T, Suzuki H, Shibata D, Jikumaru Y, Hanada A, Kamiya Y, Shirasu K. Novel plant immune-priming compounds identified via high-throughput chemical screening target salicylic acid glucosyltransferases in Arabidopsis. Plant Cell 2012; 24:3795-804. [PMID: 22960909 PMCID: PMC3480303 DOI: 10.1105/tpc.112.098343] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Plant activators are compounds, such as analogs of the defense hormone salicylic acid (SA), that protect plants from pathogens by activating the plant immune system. Although some plant activators have been widely used in agriculture, the molecular mechanisms of immune induction are largely unknown. Using a newly established high-throughput screening procedure that screens for compounds that specifically potentiate pathogen-activated cell death in Arabidopsis thaliana cultured suspension cells, we identified five compounds that prime the immune response. These compounds enhanced disease resistance against pathogenic Pseudomonas bacteria in Arabidopsis plants. Pretreatments increased the accumulation of endogenous SA, but reduced its metabolite, SA-O-β-d-glucoside. Inducing compounds inhibited two SA glucosyltransferases (SAGTs) in vitro. Double knockout plants that lack both SAGTs consistently exhibited enhanced disease resistance. Our results demonstrate that manipulation of the active free SA pool via SA-inactivating enzymes can be a useful strategy for fortifying plant disease resistance and may identify useful crop protectants.
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Affiliation(s)
- Yoshiteru Noutoshi
- Research Core for Interdisciplinary Sciences, Okayama University, Kita-ku, Okayama 700-8530, Japan.
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33
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Shigeyama T, Tominaga A, Arima S, Sakai T, Inada S, Jikumaru Y, Kamiya Y, Uchiumi T, Abe M, Hashiguchi M, Akashi R, Hirsch AM, Suzuki A. Additional cause for reduced JA-Ile in the root of a Lotus japonicus phyB mutant. Plant Signal Behav 2012; 7:746-748. [PMID: 22751318 PMCID: PMC3583954 DOI: 10.4161/psb.20407] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Light is critical for supplying carbon for use in the energetically expensive process of nitrogen-fixing symbiosis between legumes and rhizobia. We recently showed that root nodule formation in phyB mutants [which have a constitutive shade avoidance syndrome (SAS) phenotype] was suppressed in white light, and that nodulation in wild-type is controlled by sensing the R/FR ratio through jasmonic acid (JA) signaling. We concluded that the cause of reduced root nodule formation in phyB mutants was the inhibition of JA-Ile production in root. Here we show that the shoot JA-Ile level of phyB mutants is higher than that of the wild-type strain MG20, suggesting that translocation of JA-Ile from shoot to root is impeded in the mutant. These results indicate that root nodule formation in phyB mutants is suppressed both by decreased JA-Ile production, caused by reduced JAR1 activity in root, and by reduced JA-Ile translocation from shoot to root.
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Affiliation(s)
- Tamaki Shigeyama
- Department of Environmental Sciences; Faculty of Agriculture; Saga University; Honjyo-machi, Saga, Japan
| | - Akiyoshi Tominaga
- Department of Environmental Sciences; Faculty of Agriculture; Saga University; Honjyo-machi, Saga, Japan
- United Graduate School of Agricultural Sciences; Kagoshima University; Korimoto, Kagoshima, Japan
| | - Susumu Arima
- Department of Environmental Sciences; Faculty of Agriculture; Saga University; Honjyo-machi, Saga, Japan
- United Graduate School of Agricultural Sciences; Kagoshima University; Korimoto, Kagoshima, Japan
| | - Tatsuya Sakai
- RIKEN Plant Science Center; Yokohama; Kanagawa, Japan
- Graduate School of Science and Technology; Niigata University; Nishiku, Niigata, Japan
| | - Sayaka Inada
- RIKEN Plant Science Center; Yokohama; Kanagawa, Japan
| | | | - Yuji Kamiya
- RIKEN Plant Science Center; Yokohama; Kanagawa, Japan
| | - Toshiki Uchiumi
- Department of Chemistry and Bioscience; Faculty of Science; Kagoshima University; Korimoto, Kagoshima, Japan
| | - Mikiko Abe
- Department of Chemistry and Bioscience; Faculty of Science; Kagoshima University; Korimoto, Kagoshima, Japan
| | - Masatsugu Hashiguchi
- Frontier Science Research Center; University of Miyazaki; Miyazaki; Miyazaki, Japan
| | - Ryo Akashi
- Frontier Science Research Center; University of Miyazaki; Miyazaki; Miyazaki, Japan
| | - Ann M. Hirsch
- Department of Molecular; Cell and Developmental Biology and Molecular Biology Institute; University of California-Los Angeles; Los Angeles, CA USA
| | - Akihiro Suzuki
- Department of Environmental Sciences; Faculty of Agriculture; Saga University; Honjyo-machi, Saga, Japan
- United Graduate School of Agricultural Sciences; Kagoshima University; Korimoto, Kagoshima, Japan
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34
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Nelissen H, Rymen B, Jikumaru Y, Demuynck K, Van Lijsebettens M, Kamiya Y, Inzé D, Beemster GTS. A local maximum in gibberellin levels regulates maize leaf growth by spatial control of cell division. Curr Biol 2012; 22:1183-7. [PMID: 22683264 DOI: 10.1016/j.cub.2012.04.065] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 03/22/2012] [Accepted: 04/18/2012] [Indexed: 10/28/2022]
Abstract
Plant growth rate is largely determined by the transition between the successive phases of cell division and expansion. A key role for hormone signaling in determining this transition was inferred from genetic approaches and transcriptome analysis in the Arabidopsis root tip. We used the developmental gradient at the maize leaf base as a model to study this transition, because it allows a direct comparison between endogenous hormone concentrations and the transitions between dividing, expanding, and mature tissue. Concentrations of auxin and cytokinins are highest in dividing tissues, whereas bioactive gibberellins (GAs) show a peak at the transition zone between the division and expansion zone. Combined metabolic and transcriptomic profiling revealed that this GA maximum is established by GA biosynthesis in the division zone (DZ) and active GA catabolism at the onset of the expansion zone. Mutants defective in GA synthesis and signaling, and transgenic plants overproducing GAs, demonstrate that altering GA levels specifically affects the size of the DZ, resulting in proportional changes in organ growth rates. This work thereby provides a novel molecular mechanism for the regulation of the transition from cell division to expansion that controls organ growth and size.
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Affiliation(s)
- Hilde Nelissen
- Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium
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35
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Plackett AR, Powers SJ, Fernandez-Garcia N, Urbanova T, Takebayashi Y, Seo M, Jikumaru Y, Benlloch R, Nilsson O, Ruiz-Rivero O, Phillips AL, Wilson ZA, Thomas SG, Hedden P. Analysis of the developmental roles of the Arabidopsis gibberellin 20-oxidases demonstrates that GA20ox1, -2, and -3 are the dominant paralogs. Plant Cell 2012; 24:941-60. [PMID: 22427334 PMCID: PMC3336139 DOI: 10.1105/tpc.111.095109] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 02/16/2012] [Accepted: 02/27/2012] [Indexed: 05/18/2023]
Abstract
Gibberellin (GA) biosynthesis is necessary for normal plant development, with later GA biosynthetic stages being governed by multigene families. Arabidopsis thaliana contains five GA 20-oxidase (GA20ox) genes, and past work has demonstrated the importance of GA20ox1 and -2 for growth and fertility. Here, we show through systematic mutant analysis that GA20ox1, -2, and -3 are the dominant paralogs; their absence results in severe dwarfism and almost complete loss of fertility. In vitro analysis revealed that GA20ox4 has full GA20ox activity, but GA20ox5 catalyzes only the first two reactions of the sequence by which GA(12) is converted to GA(9). GA20ox3 functions almost entirely redundantly with GA20ox1 and -2 at most developmental stages, including the floral transition, while GA20ox4 and -5 have very minor roles. These results are supported by analysis of the gene expression patterns in promoter:β-glucuronidase reporter lines. We demonstrate that fertility is highly sensitive to GA concentration, that GA20ox1, -2, and -3 have significant effects on floral organ growth and anther development, and that both GA deficiency and overdose impact on fertility. Loss of GA20ox activity causes anther developmental arrest, with the tapetum failing to degrade. Some phenotypic recovery of late flowers in GA-deficient mutants, including ga1-3, indicated the involvement of non-GA pathways in floral development.
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Affiliation(s)
- Andrew R.G. Plackett
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Stephen J. Powers
- Biomathematics and Bioinformatics Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Nieves Fernandez-Garcia
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Terezie Urbanova
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | | | - Mitsunori Seo
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | - Yusuke Jikumaru
- RIKEN Plant Science Center, Yokohama, Kanagawa 230-0045, Japan
| | - Reyes Benlloch
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-90183 Umea, Sweden
| | - Ove Nilsson
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-90183 Umea, Sweden
| | - Omar Ruiz-Rivero
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Andrew L. Phillips
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Zoe A. Wilson
- School of Biosciences, University of Nottingham, Loughborough, Leicestershire LE12 5RD, United Kingdom
| | - Stephen G. Thomas
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
| | - Peter Hedden
- Plant Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
- Address correspondence to
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36
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Stotz HU, Jikumaru Y, Shimada Y, Sasaki E, Stingl N, Mueller MJ, Kamiya Y. Jasmonate-dependent and COI1-independent defense responses against Sclerotinia sclerotiorum in Arabidopsis thaliana: auxin is part of COI1-independent defense signaling. Plant Cell Physiol 2011; 52:1941-56. [PMID: 21937677 DOI: 10.1093/pcp/pcr127] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The jasmonate receptor COI1 is known to facilitate plant defense responses against necrotrophic pathogens, including the ascomycete Sclerotinia sclerotiorum. However, it is not known to what extent jasmonates contribute to defense nor have COI1-independent defense pathways been sufficiently characterized. Here we show that the susceptibility to S. sclerotiorum of the aos mutant, deficient in biosynthesis of jasmonic acid (JA) and its precursor 12-oxophytadienoic acid, was elevated to a level reminiscent of that of hypersusceptible coi1 mutants. In contrast, susceptibility of the JA-deficient opr3 mutant was comparable with that of the wild type. A set of 99 genes responded similarly to infection with S. sclerotiorum in wild-type and coi1 mutant leaves. Expression of this COI1-independent gene set correlated with known differences in gene expression between wild-type plants and a mutant in the transcriptional repressor auxin response factor 2 (arf2). Susceptibility to S. sclerotiorum was reduced in two arf2 mutants early during infection, implicating ARF2 as a negative regulator of defense responses against this pathogen. Hypersusceptibility of an axr1 mutant to S. sclerotiorum confirmed the contribution of auxin action to defense responses against this fungal pathogen.
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Affiliation(s)
- Henrik U Stotz
- RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.
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37
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Takeuchi K, Gyohda A, Tominaga M, Kawakatsu M, Hatakeyama A, Ishii N, Shimaya K, Nishimura T, Riemann M, Nick P, Hashimoto M, Komano T, Endo A, Okamoto T, Jikumaru Y, Kamiya Y, Terakawa T, Koshiba T. RSOsPR10 expression in response to environmental stresses is regulated antagonistically by jasmonate/ethylene and salicylic acid signaling pathways in rice roots. Plant Cell Physiol 2011; 52:1686-96. [PMID: 21828106 DOI: 10.1093/pcp/pcr105] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plant roots play important roles not only in the absorption of water and nutrients, but also in stress tolerance. Previously, we identified RSOsPR10 as a root-specific pathogenesis-related (PR) protein induced by drought and salt treatments in rice. Transcripts and proteins of RSOsPR10 were strongly induced by jasmonate (JA) and the ethylene (ET) precursor 1-aminocyclopropane-1-carboxylic acid (ACC), while salicylic acid (SA) almost completely suppressed these inductions. Immunohistochemical analyses showed that RSOsPR10 strongly accumulated in cortex cells surrounding the vascular system of roots, and this accumulation was also suppressed when SA was applied simultaneously with stress or hormone treatments. In the JA-deficient mutant hebiba, RSOsPR10 expression was up-regulated by NaCl, wounding, drought and exogenous application of JA. This suggested the involvement of a signal transduction pathway that integrates JA and ET signals in plant defense responses. Expression of OsERF1, a transcription factor in the JA/ET pathway, was induced earlier than that of RSOsPR10 after salt, JA and ACC treatments. Simultaneous SA treatment strongly inhibited the induction of RSOsPR10 expression and, to a lesser extent, induction of OsERF1 expression. These results suggest that JA/ET and SA pathways function in the stress-responsive induction of RSOsPR10, and that OsERF1 may be one of the transcriptional factors in the JA/ET pathway.
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Affiliation(s)
- Kaoru Takeuchi
- Department of Biological Sciences, Tokyo Metropolitan University, Minami-Osawa, Hachioji, Tokyo, 192-0397 Japan
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38
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Yoshimitsu Y, Tanaka K, Fukuda W, Asami T, Yoshida S, Hayashi KI, Kamiya Y, Jikumaru Y, Shigeta T, Nakamura Y, Matsuo T, Okamoto S. Transcription of DWARF4 plays a crucial role in auxin-regulated root elongation in addition to brassinosteroid homeostasis in Arabidopsis thaliana. PLoS One 2011; 6:e23851. [PMID: 21909364 PMCID: PMC3166115 DOI: 10.1371/journal.pone.0023851] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 07/25/2011] [Indexed: 11/19/2022] Open
Abstract
The expression of DWARF4 (DWF4), which encodes a C-22 hydroxylase, is crucial for brassinosteroid (BR) biosynthesis and for the feedback control of endogenous BR levels. To advance our knowledge of BRs, we examined the effects of different plant hormones on DWF4 transcription in Arabidopsis thaliana. Semi-quantitative reverse-transcriptase PCR showed that the amount of the DWF4 mRNA precursor either decreased or increased, similarly with its mature form, in response to an exogenously applied bioactive BR, brassinolide (BL), and a BR biosynthesis inhibitor, brassinazole (Brz), respectively. The response to these chemicals in the levels of β-glucuronidase (GUS) mRNA and its enzymatic activity is similar to the response of native DWF4 mRNA in DWF4::GUS plants. Contrary to the effects of BL, exogenous auxin induced GUS activity, but this enhancement was suppressed by anti-auxins, such as α-(phenylethyl-2-one)-IAA and α-tert-butoxycarbonylaminohexyl-IAA, suggesting the involvement of SCF(TIR1)-mediated auxin signaling in auxin-induced DWF4 transcription. Auxin-enhanced GUS activity was observed exclusively in roots; it was the most prominent in the elongation zones of both primary and lateral roots. Furthermore, auxin-induced lateral root elongation was suppressed by both Brz application and the dwf4 mutation, and this suppression was rescued by BL, suggesting that BRs act positively on root elongation under the control of auxin. Altogether, our results indicate that DWF4 transcription plays a novel role in the BR-auxin crosstalk associated with root elongation, in addition to its role in BR homeostasis.
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Affiliation(s)
- Yuya Yoshimitsu
- Department of Agricultural Sciences and Natural Resources, Kagoshima University, Kagoshima, Japan
| | - Kiwamu Tanaka
- Division of Plant Sciences, University of Missouri, Columbia, Missouri, United States of America
| | - Wataru Fukuda
- Department of Agricultural Sciences and Natural Resources, Kagoshima University, Kagoshima, Japan
| | - Tadao Asami
- Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Shigeo Yoshida
- RIKEN, Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Ken-ichiro Hayashi
- Department of Biochemistry, Okayama University of Science, Okayama, Japan
| | - Yuji Kamiya
- RIKEN, Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Yusuke Jikumaru
- RIKEN, Plant Science Center, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Tomoaki Shigeta
- Department of Biochemical Science and Technology, Kagoshima University, Kagoshima, Japan
| | - Yasushi Nakamura
- Department of Food Sciences and Nutritional Health, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto, Japan
| | - Tomoaki Matsuo
- Department of Biochemical Science and Technology, Kagoshima University, Kagoshima, Japan
| | - Shigehisa Okamoto
- Department of Agricultural Sciences and Natural Resources, Kagoshima University, Kagoshima, Japan
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Oikawa A, Otsuka T, Jikumaru Y, Yamaguchi S, Matsuda F, Nakabayashi R, Takashina T, Isuzugawa K, Saito K, Shiratake K. Effects of freeze-drying of samples on metabolite levels in metabolome analyses. J Sep Sci 2011; 34:3561-7. [PMID: 21898815 DOI: 10.1002/jssc.201100466] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 07/15/2011] [Accepted: 07/15/2011] [Indexed: 01/14/2023]
Abstract
Freeze-drying (FD) is a useful technique for removing water from biological tissues, such as food samples. Cellular components freeze at once, and the ice sublimates under conditions of high vacuum and low temperatures. Because biological activity is restricted during FD, the degradation of cellular metabolites is often believed to be limited. However, the cellular structure is damaged by several factors, such as the increase in cell volume during freezing, and this has serious effects on the levels of some cellular metabolites. We studied these effects of FD on metabolite levels when using it as a sample preparation step in metabolome analysis. We observed significant decreases in the levels of some metabolites, such as succinate and choline, in Arabidopsis and pear, respectively. We also found that the effects of FD on certain metabolite levels differed between Arabidopsis plants and pear fruits. These results suggest that it is necessary to confirm the metabolite recovery in each sample species when FD is used for sample preparation.
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Affiliation(s)
- Akira Oikawa
- RIKEN Plant Science Center (Tsuruoka), Tsuruoka, Japan.
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Robert-Seilaniantz A, MacLean D, Jikumaru Y, Hill L, Yamaguchi S, Kamiya Y, Jones JDG. The microRNA miR393 re-directs secondary metabolite biosynthesis away from camalexin and towards glucosinolates. Plant J 2011; 67:218-31. [PMID: 21457368 DOI: 10.1111/j.1365-313x.2011.04591.x] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
flg22 treatment increases levels of miR393, a microRNA that targets auxin receptors. Over-expression of miR393 renders plants more resistant to biotroph pathogens and more susceptible to necrotroph pathogens. In contrast, over-expression of AFB1, an auxin receptor whose mRNA is partially resistant to miR393 degradation, renders the plant more susceptible to biotroph pathogens. Here we investigate the mechanism by which auxin signalling and miR393 influence plant defence. We show that auxin signalling represses SA levels and signalling. We also show that miR393 represses auxin signalling, preventing it from antagonizing SA signalling. In addition, over-expression of miR393 increases glucosinolate levels and decreases the levels of camalexin. Further studies on pathogen interactions in auxin signalling mutants revealed that ARF1 and ARF9 negatively regulate glucosinolate accumulation, and that ARF9 positively regulates camalexin accumulation. We propose that the action of miR393 on auxin signalling triggers two complementary responses. First, it prevents suppression of SA levels by auxin. Second, it stabilizes ARF1 and ARF9 in inactive complexes. As a result, the plant is able to mount a full SA response and to re-direct metabolic flow toward the most effective anti-microbial compounds for biotroph resistance. We propose that miR393 levels can fine-tune plant defences and prioritize resources.
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Okamoto M, Kushiro T, Jikumaru Y, Abrams SR, Kamiya Y, Seki M, Nambara E. ABA 9'-hydroxylation is catalyzed by CYP707A in Arabidopsis. Phytochemistry 2011; 72:717-22. [PMID: 21414645 DOI: 10.1016/j.phytochem.2011.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 12/08/2010] [Accepted: 02/08/2011] [Indexed: 05/18/2023]
Abstract
Abscisic acid (ABA) catabolism is important for regulating endogenous ABA levels. To date, most effort has focused on catabolism of ABA to phaseic acid (PA), which is generated spontaneously after 8'-hydroxylation of ABA by cytochrome P450s in the CYP707A subfamily. Neophaseic acid (neoPA) is another well-documented ABA catabolite that is produced via ABA 9'-hydroxylation, but the 9'-hydroxylase has not yet been defined. Here, we show that endogenous neoPA levels are reduced in loss-of-function mutants defective in CYP707A genes. In addition, in planta levels of both neoPA and PA are reduced after treatment of plants with uniconazole-P, a P450 inhibitor. These lines of evidence suggest that CYP707A genes also encode the 9'-hydroxylase required for neoPA synthesis. To test this, in vitro enzyme assays using microsomal fractions from CYP707A-expressing yeast strains were conducted and these showed that all four Arabidopsis CYP707As are 9'-hydroxylases, although this activity is minor. Collectively, our results demonstrate that ABA 9'-hydroxylation is catalyzed by CYP707As as a side reaction.
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Gallego-Giraldo L, Jikumaru Y, Kamiya Y, Tang Y, Dixon RA. Selective lignin downregulation leads to constitutive defense response expression in alfalfa (Medicago sativa L.). New Phytol 2011. [PMID: 21251001 DOI: 10.1111/nph.2011.190.issue-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
• Downregulation of hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) in alfalfa (Medicago sativa) reduces lignin levels and improves forage quality and saccharification efficiency for bioethanol production. However, the plants have reduced stature. It was previously reported that HCT-down-regulated Arabidopsis have impaired auxin transport, but this has recently been disproved. • To address the basis for the phenotypes of lignin-modified alfalfa, we measured auxin transport, profiled a range of metabolites including flavonoids and hormones, and performed in depth transcriptome analyses. • Auxin transport is unaffected in HCT antisense alfalfa despite increased flavonoid biosynthesis. The plants show increased cytokinin and reduced auxin levels, and gibberellin levels and sensitivity are both reduced. Levels of salicylic, jasmonic and abscisic acids are elevated, associated with massive upregulation of pathogenesis and abiotic stress-related genes and enhanced tolerance to fungal infection and drought. • We suggest that HCT downregulated alfalfa plants exhibit constitutive activation of defense responses, triggered by release of bioactive cell wall fragments and production of hydrogen peroxide as a result of impaired secondary cell wall integrity.
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Gallego-Giraldo L, Jikumaru Y, Kamiya Y, Tang Y, Dixon RA. Selective lignin downregulation leads to constitutive defense response expression in alfalfa (Medicago sativa L.). New Phytol 2011; 190:627-39. [PMID: 21251001 DOI: 10.1111/j.1469-8137.2010.03621.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
• Downregulation of hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) in alfalfa (Medicago sativa) reduces lignin levels and improves forage quality and saccharification efficiency for bioethanol production. However, the plants have reduced stature. It was previously reported that HCT-down-regulated Arabidopsis have impaired auxin transport, but this has recently been disproved. • To address the basis for the phenotypes of lignin-modified alfalfa, we measured auxin transport, profiled a range of metabolites including flavonoids and hormones, and performed in depth transcriptome analyses. • Auxin transport is unaffected in HCT antisense alfalfa despite increased flavonoid biosynthesis. The plants show increased cytokinin and reduced auxin levels, and gibberellin levels and sensitivity are both reduced. Levels of salicylic, jasmonic and abscisic acids are elevated, associated with massive upregulation of pathogenesis and abiotic stress-related genes and enhanced tolerance to fungal infection and drought. • We suggest that HCT downregulated alfalfa plants exhibit constitutive activation of defense responses, triggered by release of bioactive cell wall fragments and production of hydrogen peroxide as a result of impaired secondary cell wall integrity.
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Ando S, Sato Y, Shigemori H, Shimizu T, Okada K, Yamane H, Jikumaru Y, Kamiya Y, Yamada K, Akimoto-Tomiyama C, Tanabe S, Nishizawa Y, Minami E. Identification and characterization of 2'-deoxyuridine from the supernatant of conidial suspensions of rice blast fungus as an infection-promoting factor in rice plants. Mol Plant Microbe Interact 2011; 24:519-532. [PMID: 21171893 DOI: 10.1094/mpmi-07-10-0172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We previously detected infection-promoting activity in the supernatant of the conidial suspension (SCS) of the rice blast fungus. In the present study, a molecule carrying the activity was purified and identified as 2'-deoxyuridine (dU). The infection-promoting activity of dU was strictly dependent on its chemical structure and displayed characteristics consistent with those of the SCS. Notably, the activity of dU was exclusively detected during interactions between rice and virulent isolates of the fungus, the number of susceptible lesions in leaf blades was increased by dU, and nonhost resistance in rice plants was not affected by treatment with dU. In addition, the expression of pathogensis-related genes, accumulation of H(2)O(2), and production of phytoalexins in rice in response to inoculation with virulent fungal isolates was not suppressed by dU. The infection-promoting activity of dU was not accompanied by elevated levels of endogenous abscissic acid, which is known to modify plant-pathogen interactions, and was not detected in interactions between oat plants and a virulent oat blast fungus isolate. Taken together, these results demonstrate that dU is a novel infection-promoting factor that acts specifically during compatible interactions between rice plants and rice blast fungus in a mode distinct from that of toxins and suppressors.
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Affiliation(s)
- Sugihiro Ando
- Division of Plant Sciences, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan
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Lin PC, Pomeranz MC, Jikumaru Y, Kang SG, Hah C, Fujioka S, Kamiya Y, Jang JC. The Arabidopsis tandem zinc finger protein AtTZF1 affects ABA- and GA-mediated growth, stress and gene expression responses. Plant J 2011; 65:253-268. [PMID: 21223390 DOI: 10.1111/tpj.2011.65.issue-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Tandem zinc finger (TZF) proteins are characterized by two zinc-binding CCCH motifs arranged in tandem. Human TZFs such as tristetraproline (TTP) bind to and trigger the degradation of mRNAs encoding cytokines and various regulators. Although the molecular functions of plant TZFs are unknown, recent genetic studies have revealed roles in hormone-mediated growth and environmental responses, as well as in the regulation of gene expression. Here we show that expression of AtTZF1 (AtCTH/AtC3H23) mRNA is repressed by a hexokinase-dependent sugar signaling pathway. However, AtTZF1 acts as a positive regulator of ABA/sugar responses and a negative regulator of GA responses, at least in part by modulating gene expression. RNAi of AtTZF1-3 caused early germination and slightly stress-sensitive phenotypes, whereas plants over-expressing AtTZF1 were compact, late flowering and stress-tolerant. The developmental phenotypes of plants over-expressing AtTZF1 were only partially rescued by exogenous application of GA, implying a reduction in the GA response or defects in other mechanisms. Likewise, the enhanced cold and drought tolerance of plants over-expressing AtTZF1 were not associated with increased ABA accumulation, suggesting that it is mainly ABA responses that are affected. Consistent with this notion, microarray analysis showed that over-expression of AtTZF1 mimics the effects of ABA or GA deficiency on gene expression. Notably, a gene network centered on a GA-inducible and ABA/sugar-repressible putative peptide hormone encoded by GASA6 was severely repressed by AtTZF1 over-expression. Hence AtTZF1 may serve as a regulator connecting sugar, ABA, GA and peptide hormone responses.
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Affiliation(s)
- Pei-Chi Lin
- Department of Plant Cellular and Molecular Biology, Plant Biotechnology Center, Ohio State University, Columbus, OH 43210, USA
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46
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Lin PC, Pomeranz MC, Jikumaru Y, Kang SG, Hah C, Fujioka S, Kamiya Y, Jang JC. The Arabidopsis tandem zinc finger protein AtTZF1 affects ABA- and GA-mediated growth, stress and gene expression responses. Plant J 2011; 65:253-68. [PMID: 21223390 DOI: 10.1111/j.1365-313x.2010.04419.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Tandem zinc finger (TZF) proteins are characterized by two zinc-binding CCCH motifs arranged in tandem. Human TZFs such as tristetraproline (TTP) bind to and trigger the degradation of mRNAs encoding cytokines and various regulators. Although the molecular functions of plant TZFs are unknown, recent genetic studies have revealed roles in hormone-mediated growth and environmental responses, as well as in the regulation of gene expression. Here we show that expression of AtTZF1 (AtCTH/AtC3H23) mRNA is repressed by a hexokinase-dependent sugar signaling pathway. However, AtTZF1 acts as a positive regulator of ABA/sugar responses and a negative regulator of GA responses, at least in part by modulating gene expression. RNAi of AtTZF1-3 caused early germination and slightly stress-sensitive phenotypes, whereas plants over-expressing AtTZF1 were compact, late flowering and stress-tolerant. The developmental phenotypes of plants over-expressing AtTZF1 were only partially rescued by exogenous application of GA, implying a reduction in the GA response or defects in other mechanisms. Likewise, the enhanced cold and drought tolerance of plants over-expressing AtTZF1 were not associated with increased ABA accumulation, suggesting that it is mainly ABA responses that are affected. Consistent with this notion, microarray analysis showed that over-expression of AtTZF1 mimics the effects of ABA or GA deficiency on gene expression. Notably, a gene network centered on a GA-inducible and ABA/sugar-repressible putative peptide hormone encoded by GASA6 was severely repressed by AtTZF1 over-expression. Hence AtTZF1 may serve as a regulator connecting sugar, ABA, GA and peptide hormone responses.
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Affiliation(s)
- Pei-Chi Lin
- Department of Plant Cellular and Molecular Biology, Plant Biotechnology Center, Ohio State University, Columbus, OH 43210, USA
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Ohkama-Ohtsu N, Sasaki-Sekimoto Y, Oikawa A, Jikumaru Y, Shinoda S, Inoue E, Kamide Y, Yokoyama T, Hirai MY, Shirasu K, Kamiya Y, Oliver DJ, Saito K. 12-oxo-phytodienoic acid-glutathione conjugate is transported into the vacuole in Arabidopsis. Plant Cell Physiol 2011; 52:205-209. [PMID: 21097476 DOI: 10.1093/pcp/pcq181] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
While exogenous toxic compounds such as herbicides are thought to be sequestered into vacuoles in the form of glutathione (GSH) conjugates, little is understood about natural plant products conjugated with GSH. To identify natural products conjugated with GSH in plants, metabolites in the Arabidopsis γ-glutamyl transpeptidase (ggt) 4 knockout mutants that are blocked in the degradation of GSH conjugates in the vacuole were compared with those in wild-type plants. Among the metabolites identified, one was confirmed to be the 12-oxo-phytodienoic acid (OPDA)-GSH conjugate, indicating that OPDA, a precursor of jasmonic acid (JA), is transported into the vacuole as a GSH conjugate.
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Kanno Y, Jikumaru Y, Hanada A, Nambara E, Abrams SR, Kamiya Y, Seo M. Comprehensive hormone profiling in developing Arabidopsis seeds: examination of the site of ABA biosynthesis, ABA transport and hormone interactions. Plant Cell Physiol 2010; 51:1988-2001. [PMID: 20959378 DOI: 10.1093/pcp/pcq158] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
ABA plays important roles in many aspects of seed development, including accumulation of storage compounds, acquisition of desiccation tolerance, induction of seed dormancy and suppression of precocious germination. Quantification of ABA in the F(1) and F(2) populations originated from crosses between the wild type and an ABA-deficient mutant aba2-2 demonstrated that ABA was synthesized in both maternal and zygotic tissues during seed development. In the absence of zygotic ABA, ABA synthesized in maternal tissues was translocated into the embryos and partially induced seed dormancy. We also analyzed the levels of ABA metabolites, gibberellins, IAA, cytokinins, jasmonates and salicylic acid (SA) in the developing seeds of the wild type and aba2-2. ABA metabolites accumulated differentially in the silique and seed tissues during development. Endogenous levels of SA were elevated in aba2-2 in the later developmental stages, whereas that of IAA was reduced compared with the wild type. These data suggest that ABA metabolism depends on developmental stages and tissues, and that ABA interacts with other hormones to regulate seed developmental processes.
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Affiliation(s)
- Yuri Kanno
- RIKEN Plant Science Center, Yokohama, Kanagawa, 230-0045 Japan
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Gonzalez N, De Bodt S, Sulpice R, Jikumaru Y, Chae E, Dhondt S, Van Daele T, De Milde L, Weigel D, Kamiya Y, Stitt M, Beemster GT, Inzé D. Increased leaf size: different means to an end. Plant Physiol 2010; 153:1261-79. [PMID: 20460583 PMCID: PMC2899902 DOI: 10.1104/pp.110.156018] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The final size of plant organs, such as leaves, is tightly controlled by environmental and genetic factors that must spatially and temporally coordinate cell expansion and cell cycle activity. However, this regulation of organ growth is still poorly understood. The aim of this study is to gain more insight into the genetic control of leaf size in Arabidopsis (Arabidopsis thaliana) by performing a comparative analysis of transgenic lines that produce enlarged leaves under standardized environmental conditions. To this end, we selected five genes belonging to different functional classes that all positively affect leaf size when overexpressed: AVP1, GRF5, JAW, BRI1, and GA20OX1. We show that the increase in leaf area in these lines depended on leaf position and growth conditions and that all five lines affected leaf size differently; however, in all cases, an increase in cell number was, entirely or predominantly, responsible for the leaf size enlargement. By analyzing hormone levels, transcriptome, and metabolome, we provide deeper insight into the molecular basis of the growth phenotype for the individual lines. A comparative analysis between these data sets indicates that enhanced organ growth is governed by different, seemingly independent pathways. The analysis of transgenic lines simultaneously overexpressing two growth-enhancing genes further supports the concept that multiple pathways independently converge on organ size control in Arabidopsis.
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Mosher S, Moeder W, Nishimura N, Jikumaru Y, Joo SH, Urquhart W, Klessig DF, Kim SK, Nambara E, Yoshioka K. The lesion-mimic mutant cpr22 shows alterations in abscisic acid signaling and abscisic acid insensitivity in a salicylic acid-dependent manner. Plant Physiol 2010; 152:1901-13. [PMID: 20164209 PMCID: PMC2850030 DOI: 10.1104/pp.109.152603] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Accepted: 02/15/2010] [Indexed: 05/19/2023]
Abstract
A number of Arabidopsis (Arabidopsis thaliana) lesion-mimic mutants exhibit alterations in both abiotic stress responses and pathogen resistance. One of these mutants, constitutive expresser of PR genes22 (cpr22), which has a mutation in two cyclic nucleotide-gated ion channels, is a typical lesion-mimic mutant exhibiting elevated levels of salicylic acid (SA), spontaneous cell death, constitutive expression of defense-related genes, and enhanced resistance to various pathogens; the majority of its phenotypes are SA dependent. These defense responses in cpr22 are suppressed under high-humidity conditions and enhanced by low humidity. After shifting plants from high to low humidity, the cpr22 mutant, but not the wild type, showed a rapid increase in SA levels followed by an increase in abscisic acid (ABA) levels. Concomitantly, genes for ABA metabolism were up-regulated in the mutant. The expression of a subset of ABA-inducible genes, such as RD29A and KIN1/2, was down-regulated, but that of other genes, like ABI1 and HAB1, was up-regulated in cpr22 after the humidity shift. cpr22 showed reduced responsiveness to ABA not only in abiotic stress responses but also in germination and stomatal closure. Double mutant analysis with nahG plants that degrade SA indicated that these alterations in ABA signaling were attributable to elevated SA levels. Furthermore, cpr22 displayed suppressed drought responses by long-term drought stress. Taken together, these results suggest an effect of SA on ABA signaling/abiotic stress responses during the activation of defense responses in cpr22.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Keiko Yoshioka
- Department of Cell and Systems Biology (S.M., W.M., W.U., E.N., K.Y.) and Center for the Analysis of Genome Evolution and Function (W.M., E.N., K.Y.), University of Toronto, Toronto, Ontario M5S 3B2, Canada; Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Molecular Genetics, University of California, San Diego, La Jolla, California 92093–0116 (N.N.); Growth Regulation Research Group, RIKEN Plant Science Center, Suehiro-cho, Tsurumi-ku, Yokohama 230–0045, Japan (Y.J., E.N.); Department of Life Science, Chung-Ang University, Seoul 156–756, South Korea (S.-H.J., S.-K.K.); and Boyce Thompson Institute for Plant Research, Ithaca, New York 14850 (D.F.K.)
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