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Singhal C, Singh A, Sharma AK, Khurana P. Identification of CKX gene family in Morus indica cv K2 and functional characterization of MiCKX4 during abiotic stress. STRESS BIOLOGY 2024; 4:35. [PMID: 39136853 PMCID: PMC11322459 DOI: 10.1007/s44154-024-00173-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 05/06/2024] [Indexed: 08/16/2024]
Abstract
Cytokinin oxidase/dehydrogenase (CKX) is the key enzyme that has been observed to catalyze irreversible inactivation of cytokinins and thus modulate cytokinin levels in plants. CKX gene family is known to have few members which are, expanded in the genome mainly due to duplication events. A total of nine MiCKXs were identified in Morus indica cv K2 with almost similar gene structures and conserved motifs and domains. The cis-elements along with expression analysis of these MiCKXs revealed their contrasting and specific role in plant development across different developmental stages. The localization of these enzymes in ER and Golgi bodies signifies their functional specification and property of getting modified post-translationally to carry out their activities. The overexpression of MiCKX4, an ortholog of AtCKX4, displayed longer primary root and higher number of lateral roots. Under ABA stress also the transgenic lines showed higher number of lateral roots and tolerance against drought stress as compared to wild-type plants. In this study, the CKX gene family members were analyzed bioinformatically for their roles under abiotic stresses.
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Affiliation(s)
- Chanchal Singhal
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Arunima Singh
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Arun Kumar Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Paramjit Khurana
- Department of Plant Molecular Biology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India.
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2
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Zhao J, Wang J, Liu J, Zhang P, Kudoyarova G, Liu CJ, Zhang K. Spatially distributed cytokinins: Metabolism, signaling, and transport. PLANT COMMUNICATIONS 2024; 5:100936. [PMID: 38689499 PMCID: PMC11287186 DOI: 10.1016/j.xplc.2024.100936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 04/25/2024] [Accepted: 04/28/2024] [Indexed: 05/02/2024]
Abstract
Cytokinins are mobile phytohormones that regulate plant growth, development, and environmental adaptability. The major cytokinin species include isopentenyl adenine (iP), trans-zeatin (tZ), cis-zeatin (cZ), and dihydrozeatin (DZ). The spatial distributions of different cytokinin species in different organelles, cells, tissues, and organs are primarily shaped by biosynthesis via isopentenyltransferases (IPT), cytochrome P450 monooxygenase, and 5'-ribonucleotide phosphohydrolase and by conjugation or catabolism via glycosyltransferase or cytokinin oxidase/dehydrogenase. Cytokinins bind to histidine receptor kinases in the endoplasmic reticulum or plasma membrane and relay signals to response regulators in the nucleus via shuttle proteins known as histidine phosphotransfer proteins. The movements of cytokinins from sites of biosynthesis to sites of signal perception usually require long-distance, intercellular, and intracellular transport. In the past decade, ATP-binding cassette (ABC) transporters, purine permeases (PUP), AZA-GUANINE RESISTANT (AZG) transporters, equilibrative nucleoside transporters (ENT), and Sugars Will Eventually Be Exported transporters (SWEET) have been characterized as involved in cytokinin transport processes. This review begins by introducing the spatial distributions of various cytokinins and the subcellular localizations of the proteins involved in their metabolism and signaling. Highlights focus on an inventory of the characterized transporters involved in cytokinin compartmentalization, including long-distance, intercellular, and intracellular transport, and the regulation of the spatial distributions of cytokinins by environmental cues. Future directions for cytokinin research are also discussed.
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Affiliation(s)
- Jiangzhe Zhao
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Jingqi Wang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Jie Liu
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Penghong Zhang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Guzel Kudoyarova
- Ufa Institute of Biology, Ufa Federal Research Center, RAS, Prospekt Oktyabrya 69, Ufa 450054, Russia
| | - Chang-Jun Liu
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Kewei Zhang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China.
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Šmeringai J, Schrumpfová PP, Pernisová M. Cytokinins - regulators of de novo shoot organogenesis. FRONTIERS IN PLANT SCIENCE 2023; 14:1239133. [PMID: 37662179 PMCID: PMC10471832 DOI: 10.3389/fpls.2023.1239133] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 07/31/2023] [Indexed: 09/05/2023]
Abstract
Plants, unlike animals, possess a unique developmental plasticity, that allows them to adapt to changing environmental conditions. A fundamental aspect of this plasticity is their ability to undergo postembryonic de novo organogenesis. This requires the presence of regulators that trigger and mediate specific spatiotemporal changes in developmental programs. The phytohormone cytokinin has been known as a principal regulator of plant development for more than six decades. In de novo shoot organogenesis and in vitro shoot regeneration, cytokinins are the prime candidates for the signal that determines shoot identity. Both processes of de novo shoot apical meristem development are accompanied by changes in gene expression, cell fate reprogramming, and the switching-on of the shoot-specific homeodomain regulator, WUSCHEL. Current understanding about the role of cytokinins in the shoot regeneration will be discussed.
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Affiliation(s)
- Ján Šmeringai
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Petra Procházková Schrumpfová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Markéta Pernisová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Brno, Czechia
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Zha M, Zhao Y, Wang Y, Chen B, Tan Z. Strigolactones and Cytokinin Interaction in Buds in the Control of Rice Tillering. FRONTIERS IN PLANT SCIENCE 2022; 13:837136. [PMID: 35845690 PMCID: PMC9286680 DOI: 10.3389/fpls.2022.837136] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Shoot branching is among the most crucial morphological traits in rice (Oryza sativa L.) and is physiologically modulated by auxins, cytokinins (CKs), and strigolactones (SLs) cumulatively in rice. A number of studies focused on the interplay of these three hormones in regulating rice tiller extension. The present study primarily aimed at determining the impact of different treatments, which were used to regulate rice tiller and axillary bud development on node 2 at the tillering stage and full heading stage, respectively. Transcription levels of several genes were quantified through qRT-PCR analysis, and an endogenous auxin and four types of CKs were determined through LC-MS/MS. Both nutrient deficiency and exogenous SL supply were found to inhibit rice tiller outgrowth by reducing the CK content in the tiller buds. Furthermore, supplying the inhibitor of both exogenous SLs and endogenous SL synthesis could also affect the expression level of OsCKX genes but not the OsIPT genes. Comparison of OsCKX gene expression pattern under exogenous SL and CK supply suggested that the induction of OsCKX expression was most likely via a CK-induced independent pathway. These results combined with the expression of CK type-A RR genes in bud support a role for SLs in regulating bud outgrowth through the regulation of local CK levels. SL functioned antagonistically with CK in regulating the outgrowth of buds on node 2, by promoting the OsCKX gene expression in buds.
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Affiliation(s)
- Manrong Zha
- College of Biology Resources and Environmental Sciences, Jishou University, Jishou, China
- Key Laboratory of Plant Resources Conservation and Utilization, College of Hunan Province, Jishou, China
| | - Yanhui Zhao
- College of Biology Resources and Environmental Sciences, Jishou University, Jishou, China
- Key Laboratory of Plant Resources Conservation and Utilization, College of Hunan Province, Jishou, China
| | - Yan Wang
- College of Biology Resources and Environmental Sciences, Jishou University, Jishou, China
- Key Laboratory of Plant Resources Conservation and Utilization, College of Hunan Province, Jishou, China
| | - Bingxian Chen
- Guangdong Key Lab for Crop Germplasm Resources Preservation and Utilization, Guangzhou, China
| | - Zecheng Tan
- College of Biology Resources and Environmental Sciences, Jishou University, Jishou, China
- Key Laboratory of Plant Resources Conservation and Utilization, College of Hunan Province, Jishou, China
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Mandal S, Ghorai M, Anand U, Roy D, Kant N, Mishra T, Mane AB, Jha NK, Lal MK, Tiwari RK, Kumar M, Radha, Ghosh A, Bhattacharjee R, Proćków J, Dey A. Cytokinins: A Genetic Target for Increasing Yield Potential in the CRISPR Era. Front Genet 2022; 13:883930. [PMID: 35559022 PMCID: PMC9086551 DOI: 10.3389/fgene.2022.883930] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 03/21/2022] [Indexed: 12/12/2022] Open
Abstract
Over the last decade, remarkable progress has been made in our understanding the phytohormones, cytokinin's (CKs) biosynthesis, perception, and signalling pathways. Additionally, it became apparent that interfering with any of these steps has a significant effect on all stages of plant growth and development. As a result of their complex regulatory and cross-talk interactions with other hormones and signalling networks, they influence and control a wide range of biological activities, from cellular to organismal levels. In agriculture, CKs are extensively used for yield improvement and management because of their wide-ranging effects on plant growth, development and physiology. One of the primary targets in this regard is cytokinin oxidase/dehydrogenase (CKO/CKX), which is encoded by CKX gene, which catalyses the irreversible degradation of cytokinin. The previous studies on various agronomically important crops indicated that plant breeders have targeted CKX directly. In recent years, prokaryotic clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system has been increasingly used in editing the CKO/CKX gene and phenomenal results have been achieved. This review provides an updated information on the applications of CRISPR-based gene-editing tools in manipulating cytokinin metabolism at the genetic level for yield improvement. Furthermore, we summarized the current developments of RNP-mediated DNA/transgene-free genomic editing of plants which would broaden the application of this technology. The current review will advance our understanding of cytokinins and their role in sustainably increase crop production through CRISPR/Cas genome editing tool.
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Affiliation(s)
- Sayanti Mandal
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, India
| | - Mimosa Ghorai
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Uttpal Anand
- CytoGene Research & Development LLP, Barabanki, Uttar Pradesh, India
| | - Debleena Roy
- PG Department of Botany, Lady Brabourne College, Kolkata, India
| | - Nishi Kant
- Department of Biotechnology, ARKA Jain University, Jamshedpur, India
| | - Tulika Mishra
- Department of Botany, DDU Gorakhpur University, Gorakhpur, India
| | - Abhijit Bhagwan Mane
- Department of Zoology, Dr. Patangrao Kadam Mahavidhyalaya, Ramanandnagar (Burli), Sangli, India
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, India
| | | | | | - Manoj Kumar
- Chemical and Biochemical Processing Division, ICAR-Central Institute for Research on Cotton Technology, Mumbai, India
| | - Radha
- School of Biological and Environmental Sciences, Shoolini University of Biotechnology and Management Sciences, Solan, India
| | - Arabinda Ghosh
- Microbiology Division, Department of Botany, Gauhati University, Guwahati, India
| | - Rahul Bhattacharjee
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT) Deemed To Be University, Bhubaneswar, India
| | - Jarosław Proćków
- Department of Plant Biology, Institute of Environmental Biology, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Abhijit Dey
- Department of Life Sciences, Presidency University, Kolkata, India
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Frébortová J, Frébort I. Biochemical and Structural Aspects of Cytokinin Biosynthesis and Degradation in Bacteria. Microorganisms 2021; 9:microorganisms9061314. [PMID: 34208724 PMCID: PMC8234997 DOI: 10.3390/microorganisms9061314] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 11/16/2022] Open
Abstract
It has been known for quite some time that cytokinins, hormones typical of plants, are also produced and metabolized in bacteria. Most bacteria can only form the tRNA-bound cytokinins, but there are examples of plant-associated bacteria, both pathogenic and beneficial, that actively synthesize cytokinins to interact with their host. Similar to plants, bacteria produce diverse cytokinin metabolites, employing corresponding metabolic pathways. The identification of genes encoding the enzymes involved in cytokinin biosynthesis and metabolism facilitated their detailed characterization based on both classical enzyme assays and structural approaches. This review summarizes the present knowledge on key enzymes involved in cytokinin biosynthesis, modifications, and degradation in bacteria, and discusses their catalytic properties in relation to the presence of specific amino acid residues and protein structure.
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Fu X, Su H, Liu S, Du X, Xu C, Luo K. Cytokinin signaling localized in phloem noncell-autonomously regulates cambial activity during secondary growth of Populus stems. THE NEW PHYTOLOGIST 2021; 230:1476-1488. [PMID: 33540480 DOI: 10.1111/nph.17255] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
The regulation of cytokinin on secondary vascular development has been uncovered by modulating cytokinin content. However, it remains unclear how cytokinin enriched in developing secondary phloem regulates cambium activity in poplar. Here, we visualized the gradient distribution of cytokinin with a peak in the secondary phloem of poplar stem via immunohistochemical imaging, and determined the role of phloem-located cytokinin signaling during wood formation. We generated transgenic poplar harboring cytokinin oxidase/dehydrogenase (CKX)2, a gene encoding a cytokinin degrading enzyme, driven by the phloem-specific CLE41b promoter, indicating that the disruption of the cytokinin gradient pattern restricts the cambial activity. The RNA interference-based knockdown of the histidine kinase (HK) genes encoding cytokinin receptors specifically in secondary phloem significantly compromised the division activity of cambial cells, whereas the phloem-specific expression of a type-B response regulator (RR) transcription factor stimulated cambial proliferation, providing evidence for the noncell-autonomous regulation of local cytokinin signaling on the cambial activity. Moreover, the cambium-specific knockdown of HKs also led to restricted cambial activity, and the defects were aggravated by the reduced cytokinin accumulation. Our results showed that local cytokinin signaling in secondary phloem regulates cambial activity noncell-autonomously, and coordinately with its local signaling in cambium.
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Affiliation(s)
- Xiaokang Fu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Huili Su
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Shuai Liu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Xuelian Du
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Changzheng Xu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Keming Luo
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing, 400715, China
- Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing, 400715, China
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Nedvěd D, Hošek P, Klíma P, Hoyerová K. Differential Subcellular Distribution of Cytokinins: How Does Membrane Transport Fit into the Big Picture? Int J Mol Sci 2021; 22:3428. [PMID: 33810428 PMCID: PMC8037549 DOI: 10.3390/ijms22073428] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/02/2021] [Accepted: 03/22/2021] [Indexed: 12/17/2022] Open
Abstract
Cytokinins are a class of phytohormones, signalling molecules specific to plants. They act as regulators of diverse physiological processes in complex signalling pathways. It is necessary for plants to continuously regulate cytokinin distribution among different organs, tissues, cells, and compartments. Such regulatory mechanisms include cytokinin biosynthesis, metabolic conversions and degradation, as well as cytokinin membrane transport. In our review, we aim to provide a thorough picture of the latter. We begin by summarizing cytokinin structures and physicochemical properties. Then, we revise the elementary thermodynamic and kinetic aspects of cytokinin membrane transport. Next, we review which membrane-bound carrier proteins and protein families recognize cytokinins as their substrates. Namely, we discuss the families of "equilibrative nucleoside transporters" and "purine permeases", which translocate diverse purine-related compounds, and proteins AtPUP14, AtABCG14, AtAZG1, and AtAZG2, which are specific to cytokinins. We also address long-distance cytokinin transport. Putting all these pieces together, we finally discuss cytokinin distribution as a net result of these processes, diverse in their physicochemical nature but acting together to promote plant fitness.
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Affiliation(s)
- Daniel Nedvěd
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
- Department of Biochemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic
| | - Petr Hošek
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
| | - Petr Klíma
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
| | - Klára Hoyerová
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
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The Hulks and the Deadpools of the Cytokinin Universe: A Dual Strategy for Cytokinin Production, Translocation, and Signal Transduction. Biomolecules 2021; 11:biom11020209. [PMID: 33546210 PMCID: PMC7913349 DOI: 10.3390/biom11020209] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 02/06/2023] Open
Abstract
Cytokinins are plant hormones, derivatives of adenine with a side chain at the N6-position. They are involved in many physiological processes. While the metabolism of trans-zeatin and isopentenyladenine, which are considered to be highly active cytokinins, has been extensively studied, there are others with less obvious functions, such as cis-zeatin, dihydrozeatin, and aromatic cytokinins, which have been comparatively neglected. To help explain this duality, we present a novel hypothesis metaphorically comparing various cytokinin forms, enzymes of CK metabolism, and their signalling and transporter functions to the comics superheroes Hulk and Deadpool. Hulk is a powerful but short-lived creation, whilst Deadpool presents a more subtle and enduring force. With this dual framework in mind, this review compares different cytokinin metabolites, and their biosynthesis, translocation, and sensing to illustrate the different mechanisms behind the two CK strategies. This is put together and applied to a plant developmental scale and, beyond plants, to interactions with organisms of other kingdoms, to highlight where future study can benefit the understanding of plant fitness and productivity.
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Gupta MK, Gouda G, Donde R, Vadde R, Behera L. Novel cytokinin oxidase/dehydrogenase inhibitors for enhancing grain yield in crop plants and potential applications in the biotechnology industry. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:153-156. [PMID: 33529340 DOI: 10.1093/jxb/eraa445] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This article comments on:Nisler J, Kopečný D, Pěkná Z, Končitíková R, Koprna R, Murvanidze N, Werbrouck SPO, Havlíček L, De Diego N, Wimmer Z, Briozzo P, Moréra S, Zalabák D, Spíchal L, Strnad M. 2021. Diphenylurea-derived cytokinin oxidase/dehydrogenase inhibitors for biotechnology and agriculture. Journal of Experimental Botany 72, 355–370.
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Affiliation(s)
- Manoj Kumar Gupta
- ICAR-National Rice Research Institute, Cuttack, Odisha, India
- Department of Biotechnology & Bioinformatics, Yogi Vemana University, Kadapa, Andhra Pradesh, India
| | - Gayatri Gouda
- ICAR-National Rice Research Institute, Cuttack, Odisha, India
| | - Ravindra Donde
- ICAR-National Rice Research Institute, Cuttack, Odisha, India
| | - Ramakrishna Vadde
- Department of Biotechnology & Bioinformatics, Yogi Vemana University, Kadapa, Andhra Pradesh, India
| | - Lambodar Behera
- ICAR-National Rice Research Institute, Cuttack, Odisha, India
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Huang X, Zhang H, Guo R, Wang Q, Liu X, Kuang W, Song H, Liao J, Huang Y, Wang Z. Systematic identification and characterization of circular RNAs involved in flag leaf senescence of rice. PLANTA 2021; 253:26. [PMID: 33410920 PMCID: PMC7790769 DOI: 10.1007/s00425-020-03544-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 12/19/2020] [Indexed: 05/30/2023]
Abstract
Circular RNAs (circRNAs) identification, expression profiles, and construction of circRNA-parental gene relationships and circRNA-miRNA-mRNA ceRNA networks indicate that circRNAs are involved in flag leaf senescence of rice. Circular RNAs (circRNAs) are a class of 3'-5' head-to-tail covalently closed non-coding RNAs which have been proved to play important roles in various biological processes. However, no systematic identification of circRNAs associated with leaf senescence in rice has been studied. In this study, a genome-wide high-throughput sequencing analysis was performed using rice flag leaves developing from normal to senescence. Here, a total of 6612 circRNAs were identified, among which, 113 circRNAs were differentially expressed (DE) during the leaf senescence process. Moreover, 4601 (69.59%) circRNAs were derived from the exons or introns of their parental genes, while 2110 (71%) of the parental genes produced only one circRNA. The sequence alignment analysis showed that hundreds of rice circRNAs were conserved among different plant species. Gene Ontology (GO) enrichment analysis revealed that parental genes of DE circRNAs were enriched in many biological processes closely related to leaf senescence. Through weighted gene co-expression network analysis (WGCNA), six continuously down-expressed circRNAs, 18 continuously up-expressed circRNAs and 15 turn-point high-expressed circRNAs were considered to be highly associated with leaf senescence. Additionally, a total of 17 senescence-associated circRNAs were predicted to have parental genes, in which, regulations of three circRNAs to their parental genes were validated by qRT-PCR. The competing endogenous RNA (ceRNA) networks were also constructed. And a total of 11 senescence-associated circRNAs were predicted to act as miRNA sponges to regulate mRNAs, in which, regulation of two circRNAs to eight mRNAs was validated by qRT-PCR. It is discussed that senescence-associated circRNAs were involved in flag leaf senescence probably through mediating their parental genes and ceRNA networks, to participate in several well-studied senescence-associated processes, mainly including the processes of transcription, translation, and posttranslational modification (especially protein glycosylation), oxidation-reduction process, involvement of senescence-associated genes, hormone signaling pathway, proteolysis, and DNA damage repair. This study not only showed the systematic identification of circRNAs involved in leaf senescence of rice, but also laid a foundation for functional research on candidate circRNAs.
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Affiliation(s)
- Xiaoping Huang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Hongyu Zhang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Rong Guo
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Qiang Wang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Xuanzhi Liu
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Weigang Kuang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Haiyan Song
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Jianglin Liao
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China
| | - Yingjin Huang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China.
| | - Zhaohai Wang
- Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education of the P.R. China, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi Province, China.
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Wang C, Wang H, Zhu H, Ji W, Hou Y, Meng Y, Wen J, Mysore KS, Li X, Lin H. Genome-wide identification and characterization of cytokinin oxidase/dehydrogenase family genes in Medicago truncatula. JOURNAL OF PLANT PHYSIOLOGY 2021; 256:153308. [PMID: 33190018 DOI: 10.1016/j.jplph.2020.153308] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/10/2020] [Accepted: 10/12/2020] [Indexed: 05/25/2023]
Abstract
Cytokinin oxidase/dehydrogenases (CKXs) play a key role in the irreversible degradation of phytohormone cytokinin that is necessary for various plant growth and development processes. However, thus far, detailed investigations of the CKX gene family in the model legume Medicago truncatula are limited. In this study, we identified 9 putative CKX homologues with conserved FAD- and cytokinin-binding domains in the M. truncatula genome. We analyzed their phylogenetic relationship, gene structure, conserved domain, expression pattern, protein subcellular locations and other properties. The tissue-specific expression profiles of the MtCKX genes are different among different members and these MtCKXs also displayed different patterns in response to synthetic cytokinin 6-benzylaminopurine (6-BA) and indole-3-acetic acid (IAA), suggesting their diverse roles in M. truncatula development. To further understand the biological function of MtCKXs, we identified and characterized mutants of each MtCKX by taking advantage of the Tnt1 mutant population in M. truncatula. Results indicated that M. truncatula plants harboring Tnt1 insertions in each single MtCKX genes showed no morphological changes in aerial parts, suggesting functional redundancy of MtCKXs in M. truncatula shoot development. However, disruption of Medtr4g126160, which is predominantly expressed in roots, leads to an obvious reduced primary root length and increased lateral root number, indicating the specific roles of cytokinin in regulating root architecture. We systematically analyzed the MtCKX gene family at the genome-wide level and revealed their possible roles in M. truncatula shoot and root development, which shed lights on understanding the biological function of CKX family genes in related legume plants.
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Affiliation(s)
- Chongnan Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Hui Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Hao Zhu
- Grassland Research Institute, Xinjiang Academy of Animal Sciences, Urumqi 830011, China
| | - Wenkai Ji
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yaling Hou
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yingying Meng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiangqi Wen
- Noble Research Institute, LLC, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Kirankumar S Mysore
- Noble Research Institute, LLC, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Xuesen Li
- Grassland Research Institute, Xinjiang Academy of Animal Sciences, Urumqi 830011, China
| | - Hao Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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13
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Xiao Y, Zhang J, Yu G, Lu X, Mei W, Deng H, Zhang G, Chen G, Chu C, Tong H, Tang W. Endoplasmic Reticulum-Localized PURINE PERMEASE1 Regulates Plant Height and Grain Weight by Modulating Cytokinin Distribution in Rice. FRONTIERS IN PLANT SCIENCE 2020; 11:618560. [PMID: 33414802 PMCID: PMC7783468 DOI: 10.3389/fpls.2020.618560] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 12/03/2020] [Indexed: 05/04/2023]
Abstract
Cytokinins (CKs) are a class of phytohormones playing essential roles in various biological processes. However, the mechanisms underlying CK transport as well as its function in plant growth and development are far from being fully elucidated. Here, we characterize the function of PURINE PERMEASE1 (OsPUP1) in rice (Oryza sativa L.). OsPUP1 was predominantly expressed in the root, particularly in vascular cells, and CK treatment can induce its expression. Subcellular localization analysis showed that OsPUP1 was predominantly localized to the endoplasmic reticulum (ER). Overexpression of OsPUP1 resulted in growth defect of various aerial tissues, including decreased leaf length, plant height, grain weight, panicle length, and grain number. Hormone profiling revealed that the CK content was decreased in the shoot of OsPUP1-overexpressing seedling, but increased in the root, compared with the wild type. The CK content in the panicle was also decreased. Quantitative reverse transcription-PCR (qRT-PCR) analysis using several CK type-A response regulators (OsRRs) as the marker genes suggested that the CK response in the shoot of OsPUP1-overexpressing seedling is decreased compared to the wild type when CKs are applied to the root. Genetic analysis revealed that BG3/OsPUP4, a putative plasma membrane-localized CK transporter, overcomes the function of OsPUP1. We hypothesize that OsPUP1 might be involved in importing CKs into ER to unload CKs from the vascular tissues by cell-to-cell transport.
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Affiliation(s)
- Yunhua Xiao
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Junwen Zhang
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Guiyuan Yu
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Xuedan Lu
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Wentao Mei
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Huabing Deng
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Guilian Zhang
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Guihua Chen
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Hongning Tong
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wenbang Tang
- Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, China
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14
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15
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Cheng HP, Yang XH, Lan L, Xie LJ, Chen C, Liu C, Chu J, Li ZY, Liu L, Zhang TQ, Luo DQ, Cheng L. Chemical Deprenylation of N 6 -Isopentenyladenosine (i 6 A) RNA. Angew Chem Int Ed Engl 2020; 59:10645-10650. [PMID: 32198805 DOI: 10.1002/anie.202003360] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/20/2020] [Indexed: 12/19/2022]
Abstract
N6 -isopentenyladenosine (i6 A) is an RNA modification found in cytokinins, which regulate plant growth/differentiation, and a subset of tRNAs, where it improves the efficiency and accuracy of translation. The installation and removal of this modification is mediated by prenyltransferases and cytokinin oxidases, and a chemical approach to selective deprenylation of i6 A has not been developed. We show that a selected group of oxoammonium cations function as artificial deprenylases to promote highly selective deprenylation of i6 A in nucleosides, oligonucleotides, and live cells. Importantly, other epigenetic modifications, amino acid residues, and natural products were not affected. Moreover, a significant phenotype difference in the Arabidopsis thaliana shoot and root development was observed with incubation of the cation. These results establish these small organic molecules as direct chemical regulators/artificial deprenylases of i6 A.
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Affiliation(s)
- Hou-Ping Cheng
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiao-Hui Yang
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, College of Life Science, Hebei University, Hebei, 071002, China
| | - Ling Lan
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Li-Jun Xie
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chuan Chen
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, College of Life Science, Hebei University, Hebei, 071002, China
| | - Cuimei Liu
- National Centre for Plant Gene Research (Beijing), Innovation Academy for Seed Design, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jinfang Chu
- National Centre for Plant Gene Research (Beijing), Innovation Academy for Seed Design, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhi-Yan Li
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Li Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tian-Qi Zhang
- National Key Laboratory of Plant Molecular Genetics (NKLPMG), CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai, 200032, China
| | - Du-Qiang Luo
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, College of Life Science, Hebei University, Hebei, 071002, China
| | - Liang Cheng
- Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
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16
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Hoyerová K, Hošek P. New Insights Into the Metabolism and Role of Cytokinin N-Glucosides in Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:741. [PMID: 32582261 PMCID: PMC7292203 DOI: 10.3389/fpls.2020.00741] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/08/2020] [Indexed: 05/18/2023]
Abstract
Cytokinin (CK) N-glucosides are the most abundant group of CK metabolites in many species; however, their physiological role in planta was for a long time perceived as irreversible storage CK forms only. Recently, a comprehensive screen showed that only vascular plants form CK N-glucosides in contrast to mosses, algae, and fungi. The formation of CK N-glucosides as biologically inactive CK conjugates thus represents an evolutionarily young mechanism for deactivation of CK bases. Even though CK N-glucosides are not biologically active themselves due to their inability to activate the CK perception system, new data on CK N-glucoside metabolism show that trans-zeatin (tZ) N7- and N9-glucosides are metabolized in vivo, efficiently releasing free CK bases that are most probably responsible for the biological activities observed in a number of bioassays. Moreover, CK N-glucosides' subcellular localization as well as their abundance in xylem both point to their possible plasma membrane transport and indicate a role also as CK transport forms. Identification of the enzyme(s) responsible for the hydrolysis of tZ N7- and N9-glucosides, as well as the discovery of putative CK N-glucoside plasma membrane transporter, would unveil important parts of the overall picture of CK metabolic interconversions and their physiological importance.
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17
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Czajkowska BI, Finlay CM, Jones G, Brown TA. Diversity of a cytokinin dehydrogenase gene in wild and cultivated barley. PLoS One 2019; 14:e0225899. [PMID: 31805120 PMCID: PMC6894797 DOI: 10.1371/journal.pone.0225899] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 11/14/2019] [Indexed: 01/09/2023] Open
Abstract
The cytokinin dehydrogenase gene HvCKX2.1 is the regulatory target for the most abundant heterochromatic small RNAs in drought-stressed barley caryopses. We investigated the diversity of HvCKX2.1 in 228 barley landraces and 216 wild accessions and identified 14 haplotypes, five of these with ten or more members, coding for four different protein variants. The third largest haplotype was abundant in wild accessions (51 members), but absent from the landrace collection. Protein structure predictions indicated that the amino acid substitution specific to haplotype 3 could result in a change in the functional properties of the HvCKX2.1 protein. Haplotypes 1–3 have overlapping geographical distributions in the wild population, but the average rainfall amounts at the collection sites for haplotype 3 plants are significantly higher during November to February compared to the equivalent data for plants of haplotypes 1 and 2. We argue that the likelihood that haplotype 3 plants were excluded from landraces by sampling bias that occurred when the first wild barley plants were taken into cultivation is low, and that it is reasonable to suggest that plants with haplotype 3 are absent from the crop because these plants were less suited to the artificial conditions associated with cultivation. Although the cytokinin signalling pathway influences many aspects of plant development, the identified role of HvCKX2.1 in the drought response raises the possibility that the particular aspect of cultivation that mitigated against haplotype 3 relates in some way to water utilization. Our results therefore highlight the possibility that water utilization properties should be looked on as a possible component of the suite of physiological adaptations accompanying the domestication and subsequent evolution of cultivated barley.
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Affiliation(s)
- Beata I. Czajkowska
- Department of Earth and Environmental Sciences, Manchester Institute of Biotechnology, University of Manchester, Manchester, England, United Kingdom
| | - Conor M. Finlay
- Lydia Becker Institute of Immunology and Inflammation, School of Biological Sciences, University of Manchester, Manchester, England, United Kingdom
| | - Glynis Jones
- Department of Archaeology, University of Sheffield, Northgate House, West Street, Sheffield, England, United Kingdom
| | - Terence A. Brown
- Department of Earth and Environmental Sciences, Manchester Institute of Biotechnology, University of Manchester, Manchester, England, United Kingdom
- * E-mail:
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18
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Zhao J, Yu N, Ju M, Fan B, Zhang Y, Zhu E, Zhang M, Zhang K. ABC transporter OsABCG18 controls the shootward transport of cytokinins and grain yield in rice. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:6277-6291. [PMID: 31504730 PMCID: PMC6859808 DOI: 10.1093/jxb/erz382] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 08/16/2019] [Indexed: 05/05/2023]
Abstract
Cytokinins are one of the most important phytohormones and play essential roles in multiple life processes in planta. Root-derived cytokinins are transported to the shoots via long-distance transport. The mechanisms of long-distance transport of root-derived cytokinins remain to be demonstrated. In this study, we report that OsABCG18, a half-size ATP-binding cassette transporter from rice (Oryza sativa L.), is essential for the long-distance transport of root-derived cytokinins. OsABCG18 encodes a plasma membrane protein and is primarily expressed in the vascular tissues of the root, stem, and leaf midribs. Cytokinin profiling, as well as [14C]trans-zeatin tracer, and xylem sap assays, demonstrated that the shootward transport of root-derived cytokinins was significantly suppressed in the osabcg18 mutants. Transport assays in tobacco (Nicotiana benthamiana) indicated that OsABCG18 exhibited efflux transport activities for various substrates of cytokinins. While the mutation reduced root-derived cytokinins in the shoot and grain yield, overexpression of OsABCG18 significantly increased cytokinins in the shoot and improved grain yield. The findings for OsABCG18 as a transporter for long-distance transport of cytokinin provide new insights into the cytokinin transport mechanism and a novel strategy to increase cytokinins in the shoot and promote grain yield.
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Affiliation(s)
- Jiangzhe Zhao
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Ningning Yu
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Min Ju
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Biao Fan
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Yanjun Zhang
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Engao Zhu
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Mengyuan Zhang
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
| | - Kewei Zhang
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, China
- Correspondence:
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19
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Gouda G, Gupta MK, Donde R, Kumar J, Vadde R, Mohapatra T, Behera L. Computational approach towards understanding structural and functional role of cytokinin oxidase/dehydrogenase 2 (CKX2) in enhancing grain yield in rice plant. J Biomol Struct Dyn 2019; 38:1158-1167. [PMID: 30896372 DOI: 10.1080/07391102.2019.1597771] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cytokinin oxidase/dehydrogenase (CKX) is the only known enzyme associated with irreversible degradation of cytokinins in plants. CKX2 contains flavin adenine dinucleotide (FAD) domain. Earlier studies utilising antisense & hpRNAi suppression techniques in mutant/transgenic rice plants revealed that when CKX2 binds with FAD, CKX2 expression reduces, which in turn causes cytokinin aggregation in inflorescence meristem that subsequently enhances both branches and grain number resulting in increased grain yield. Owing to the non-existence of complete three-dimensional structure of CKX2, insight into the structure and function of CKX2 and its relationship with its cofactor FAD is still a topic of debate. In the present study, computational approach was employed to estimate the three-dimensional structure of CKX2 through comparative modelling approach. Later, CKX2 and FAD interaction study was performed to understand the underlying mechanism involved with reduced expression of CKX2. Molecular dynamic simulation studies of both CKX2 and CKX-FAD complex revealed that after binding with FAD, CKX2 experienced increased pressure and reduced RMSD, potential energy and free energy landscape energy, which in turn lessen anti-correlation between almost all α and β strands and random motion of C-α, subsequently reducing CKX2 expression. In near future, these information can be utilised for increasing rice yield under irrigated field condition by introgression of Gn1a gene through marker assisted back-crossing breeding. AbbreviationsGROMACSGROningen MAchine for Chemical SimulationsNPTConstant Number of Particles, Volume and TemperatureRMSDRoot Mean Square DeviationRMSFRoot Mean Square FluctuationsQTLquantitative trait lociFADflavin adenine dinucleotideNVTConstant Number of Particles, Pressure and TemperatureLINCSLinear Constraint SolverCKX2Cytokinin oxidase/dehydrogenase 2MM/PBSAMolecular Mechanics/Poisson-Boltzmann surface areaSDFStructure Data FileCommunicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Gayatri Gouda
- ICAR-National Rice Research Institute, Cuttack, India
| | - Manoj Kumar Gupta
- Department of Biotechnology & Bioinformatics, Yogi Vemana University, Kadapa, India
| | | | | | - Ramakrishna Vadde
- Department of Biotechnology & Bioinformatics, Yogi Vemana University, Kadapa, India
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Li Y, Song G, Gao J, Zhang S, Zhang R, Li W, Chen M, Liu M, Xia X, Risacher T, Li G. Enhancement of grain number per spike by RNA interference of cytokinin oxidase 2 gene in bread wheat. Hereditas 2018; 155:33. [PMID: 30305809 PMCID: PMC6169005 DOI: 10.1186/s41065-018-0071-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 09/21/2018] [Indexed: 11/23/2022] Open
Abstract
Background This study aimed to validate the function of CKX gene on grain numbers in wheat. Methods we constructed and transformed a RNA interference expression vector of TaCKX2.4 in bread wheat line NB1. Southern blotting analysis was used to select transgenic plants with single copy. The expression of TaCKX2.4 gene was estimated by Quantitative real-time PCR (qRT-PCR) analysis. Finally, the relation between expression of TaCKX2.4 gene and grain numbers was validated. Results Totally, 20 positive independent events were obtained. Homozygous lines from 5 events with a single copy of transformed gene each were selected to evaluate the expression of TaCKX2.4 and grain numbers per spike in T3 generation. Compared with the control NB1, the average grain numbers per spike significantly increased by 12.6%, 8.3%, 6.5% and 5.8% in the T3 lines JW39-3A, JW1-2B, JW1-1A and JW5-1A, respectively. Conclusion Our study indicated that the expression level of TaCKX2.4 was negatively correlated with the grain number per spike, indicating that the reduced expression of TaCKX2.4 increased grain numbers per spike in wheat.
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Affiliation(s)
- Yulian Li
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Guoqi Song
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Jie Gao
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Shujuan Zhang
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Rongzhi Zhang
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Wei Li
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Mingli Chen
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Min Liu
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
| | - Xianchun Xia
- 3Institute of Crop Sciences, National Wheat Improvement Center, Chinese Academy of Agricultural Sciences (CAAS), 12 Zhongguancun South Street, Beijing, 100081 China
| | | | - Genying Li
- Crop Research Institute, Shandong Academy of Agricultural Sciences; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, National Engineering Laboratory for Wheat and Maize, Jinan, 250100 Shandong China
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21
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Cai L, Zhang L, Fu Q, Xu ZF. Identification and expression analysis of cytokinin metabolic genes IPTs, CYP735A and CKXs in the biofuel plant Jatropha curcas. PeerJ 2018; 6:e4812. [PMID: 29785355 PMCID: PMC5960259 DOI: 10.7717/peerj.4812] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 04/30/2018] [Indexed: 11/28/2022] Open
Abstract
The seed oil of Jatropha curcas is considered a potential bioenergy source that could replace fossil fuels. However, the seed yield of Jatropha is low and has yet to be improved. We previously reported that exogenous cytokinin treatment increased the seed yield of Jatropha. Cytokinin levels are directly regulated by isopentenyl transferase (IPT), cytochrome P450 monooxygenase, family 735, subfamily A (CYP735A), and cytokinin oxidase/dehydrogenase (CKX). In this study, we cloned six IPT genes, one JcCYP735A gene, and seven JcCKX genes. The expression patterns of these 14 genes in various organs were determined using real-time quantitative PCR. JcIPT1 was primarily expressed in roots and seeds, JcIPT2 was expressed in roots, apical meristems, and mature leaves, JcIPT3 was expressed in stems and mature leaves, JcIPT5 was expressed in roots and mature leaves, JcIPT6 was expressed in seeds at 10 days after pollination, and JcIPT9 was expressed in mature leaves. JcCYP735A was mainly expressed in roots, flower buds, and seeds. The seven JcCKX genes also showed different expression patterns in different organs of Jatropha. In addition, CK levels were detected in flower buds and seeds at different stages of development. The concentration of N6-(Δ2-isopentenyl)-adenine (iP), iP-riboside, and trans-zeatin (tZ) increased with flower development, and the concentration of iP decreased with seed development, while that of tZ increased. We further analyzed the function of JcCYP735A using the CRISPR-Cas9 system, and found that the concentrations of tZ and tZ-riboside decreased significantly in the Jccyp735a mutants, which showed severely retarded growth. These findings will be helpful for further studies of the functions of cytokinin metabolic genes and understanding the roles of cytokinins in Jatropha growth and development.
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Affiliation(s)
- Li Cai
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Lu Zhang
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan, China.,National Engineering Research Center for Ornamental Horticulture, Flower Research Institute of Yunnan Academy of Agricultural Sciences, Kunming, Yunnan, China
| | - Qiantang Fu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan, China
| | - Zeng-Fu Xu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan, China
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22
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De Novo Sequencing and Assembly Analysis of Transcriptome in Pinus bungeana Zucc. ex Endl. FORESTS 2018. [DOI: 10.3390/f9030156] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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23
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Visser M, Cook G, Burger JT, Maree HJ. In silico analysis of the grapefruit sRNAome, transcriptome and gene regulation in response to CTV-CDVd co-infection. Virol J 2017; 14:200. [PMID: 29058618 PMCID: PMC5651572 DOI: 10.1186/s12985-017-0871-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 10/16/2017] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Small RNA (sRNA) associated gene regulation has been shown to play a significant role during plant-pathogen interaction. In commercial citrus orchards co-infection of Citrus tristeza virus (CTV) and viroids occur naturally. METHODS A next-generation sequencing-based approach was used to study the sRNA and transcriptional response in grapefruit to the co-infection of CTV and Citrus dwarfing viroid. RESULTS The co-infection resulted in a difference in the expression of a number of sRNA species when comparing healthy and infected plants; the majority of these were derived from transcripts processed in a phased manner. Several RNA transcripts were also differentially expressed, including transcripts derived from two genes, predicted to be under the regulation of sRNAs. These genes are involved in plant hormone systems; one in the abscisic acid, and the other in the cytokinin regulatory pathway. Additional analysis of virus- and viroid-derived small-interfering RNAs (siRNAs) showed areas on the pathogen genomes associated with increased siRNA synthesis. Most interestingly, the starting position of the p23 silencing suppressor's sub-genomic RNA generated a siRNA hotspot on the CTV genome. CONCLUSIONS This study showed the involvement of various genes, as well as endogenous and exogenous RNA-derived sRNA species in the plant-defence response. The results highlighted the role of sRNA-directed plant hormone regulation during biotic stress, as well as a counter-response of plants to virus suppressors of RNA-silencing.
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Affiliation(s)
- Marike Visser
- Department of Genetics, Stellenbosch University, Stellenbosch, South Africa
| | - Glynnis Cook
- Department of Genetics, Stellenbosch University, Stellenbosch, South Africa
- Citrus Research International, Nelspruit, South Africa
| | - Johan T. Burger
- Department of Genetics, Stellenbosch University, Stellenbosch, South Africa
| | - Hans J. Maree
- Department of Genetics, Stellenbosch University, Stellenbosch, South Africa
- Agricultural Research Council, Infruitec-Nietvoorbij: Institute for Deciduous Fruit, Vines and Wine, Stellenbosch, South Africa
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Nanda AK, Pujol V, Wissuwa M. Patterns of stress response and tolerance based on transcriptome profiling of rice crown tissue under zinc deficiency. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1715-1729. [PMID: 28369468 DOI: 10.1093/jxb/erx039] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Zinc (Zn) deficiency is the most prevalent micronutrient disorder in rice and leads to delayed development and decreased yield. Several studies have investigated how rice plants respond to Zn deficiency and examined the differences between Zn-efficient (ZE) and Zn-inefficient (ZI) genotypes. ZE genotypes reallocate more Zn to roots and are better at maintaining crown root development than ZI genotypes in response to Zn deficiency. However, little is known about the molecular mechanisms controlling these differences. Moreover, the role of the crown, the part of the stem from which crown roots emerge, has yet to be examined. In this study we highlight the molecular mechanisms triggered by early Zn deficiency in crown tissue through RNA sequencing of two contrasting groups of several ZE and ZI genotypes. This method allowed us to (i) identify several novel and well-known Zn transporters involved in Zn retranslocation from the crown to the shoot and roots in response to Zn deficiency; (ii) determine that Zn deficiency triggers the conversion of soluble sugars into starch; and (iii) detect several candidate genes possibly conferring Zn efficiency, including a monosaccharide transporter, a Zn finger domain-containing protein, a gibberellin-stimulated family protein and a plasma membrane polypeptide family protein.
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Affiliation(s)
- Amrit K Nanda
- Crop, Livestock and Environment Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Japan
| | - Vincent Pujol
- Crop, Livestock and Environment Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Japan
| | - Matthias Wissuwa
- Crop, Livestock and Environment Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Japan
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Hluska T, Šebela M, Lenobel R, Frébort I, Galuszka P. Purification of Maize Nucleotide Pyrophosphatase/Phosphodiesterase Casts Doubt on the Existence of Zeatin Cis- Trans Isomerase in Plants. FRONTIERS IN PLANT SCIENCE 2017; 8:1473. [PMID: 28878803 PMCID: PMC5572937 DOI: 10.3389/fpls.2017.01473] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/08/2017] [Indexed: 05/14/2023]
Abstract
Almost 25 years ago, an enzyme named zeatin cis-trans isomerase from common bean has been described by Bassil et al. (1993). The partially purified enzyme required an external addition of FAD and dithiothreitol for the conversion of cis-zeatin to its trans- isomer that occurred only under light. Although an existence of this important enzyme involved in the metabolism of plant hormones cytokinins was generally accepted by plant biologists, the corresponding protein and encoding gene have not been identified to date. Based on the original paper, we purified and identified an enzyme from maize, which shows the described zeatin cis-trans isomerase activity. The enzyme belongs to nucleotide pyrophosphatase/phosphodiesterase family, which is well characterized in mammals, but less known in plants. Further experiments with the recombinant maize enzyme obtained from yeast expression system showed that rather than the catalytic activity of the enzyme itself, a non-enzymatic flavin induced photoisomerization is responsible for the observed zeatin cis-trans interconversion in vitro. An overexpression of the maize nucleotide pyrophosphatase/phosphodiesterase gene led to decreased FAD and increased FMN and riboflavin contents in transgenic Arabidopsis plants. However, neither contents nor the ratio of zeatin isomers was altered suggesting that the enzyme is unlikely to catalyze the interconversion of zeatin isomers in vivo. Using enhanced expression of a homologous gene, functional nucleotide pyrophosphatase/phosphodiesterase was also identified in rice.
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Affiliation(s)
- Tomáš Hluska
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University OlomoucOlomouc, Czechia
| | - Marek Šebela
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University OlomoucOlomouc, Czechia
| | - René Lenobel
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University OlomoucOlomouc, Czechia
| | - Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University OlomoucOlomouc, Czechia
| | - Petr Galuszka
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University OlomoucOlomouc, Czechia
- *Correspondence: Petr Galuszka,
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26
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Improvement of Sorghum Crop through Exogenous Application of Natural Growth-Promoting Substances under a Changing Climate. SUSTAINABILITY 2016. [DOI: 10.3390/su8121330] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zalabák D, Johnová P, Plíhal O, Šenková K, Šamajová O, Jiskrová E, Novák O, Jackson D, Mohanty A, Galuszka P. Maize cytokinin dehydrogenase isozymes are localized predominantly to the vacuoles. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 104:114-24. [PMID: 27031423 DOI: 10.1016/j.plaphy.2016.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 03/09/2016] [Accepted: 03/10/2016] [Indexed: 05/12/2023]
Abstract
The maize genome encompasses 13 genes encoding for cytokinin dehydrogenase isozymes (CKXs). These enzymes are responsible for irreversible degradation of cytokinin plant hormones and thus, contribute regulating their levels. Here, we focus on the unique aspect of CKXs: their diverse subcellular distribution, important in regulating cytokinin homeostasis. Maize CKXs were tagged with green fluorescent protein (GFP) and transiently expressed in maize protoplasts. Most of the isoforms, namely ZmCKX1, ZmCKX2, ZmCKX4a, ZmCKX5, ZmCKX6, ZmCKX8, ZmCKX9, and ZmCKX12, were associated with endoplasmic reticulum (ER) several hours after transformation. GFP-fused CKXs were observed to accumulate in putative prevacuolar compartments. To gain more information about the spatiotemporal localization of the above isoforms, we prepared stable expression lines of all ZmCKX-GFP fusions in Arabidopsis thaliana Ler suspension culture. All the ER-associated isoforms except ZmCKX1 and ZmCKX9 were found to be targeted primarily to vacuoles, suggesting that ER-localization is a transition point in the intracellular secretory pathway and vacuoles serve as these isoforms' final destination. ZmCKX9 showed an ER-like localization pattern similar to those observed in the transient maize assay. Apoplastic localization of ZmCKX1 was further confirmed and ZmCKX10 showed cytosolic/nuclear localization due to the absence of the signal peptide sequence as previously reported. Additionally, we prepared GFP-fused N-terminal signal deletion mutants of ZmCKX2 and ZmCKX9 and clearly demonstrated that the localization pattern of these mutant forms was cytosolic/nuclear. This study provides the first complex model for spatiotemporal localization of the key enzymes of the cytokinin degradation/catabolism in monocotyledonous plants.
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Affiliation(s)
- David Zalabák
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Patricie Johnová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Ondřej Plíhal
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Karolina Šenková
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Olga Šamajová
- Department of Cell Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Eva Jiskrová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - Ondřej Novák
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic
| | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Amitabh Mohanty
- DuPont Pioneer Ag Biotech, DuPont Knowledge Centre, Turkapally Village, Hyderabad 500078, Telangana, India
| | - Petr Galuszka
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 27, Olomouc 783 71, Czech Republic.
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Nguyen QT, Kisiala A, Andreas P, Neil Emery R, Narine S. Soybean Seed Development: Fatty Acid and Phytohormone Metabolism and Their Interactions. Curr Genomics 2016; 17:241-60. [PMID: 27252591 PMCID: PMC4869011 DOI: 10.2174/1389202917666160202220238] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/27/2015] [Accepted: 08/04/2015] [Indexed: 12/20/2022] Open
Abstract
Vegetable oil utilization is determined by its fatty acid composition. In soybean and other grain crops, during the seed development oil accumulation is important trait for value in food or industrial applications. Seed development is relatively short and sensitive to unfavorable abiotic conditions. These stresses can lead to a numerous undesirable qualitative as well as quantitative changes in fatty acid production. Fatty acid manipulation which targets a higher content of a specific single fatty acid for food or industrial application has gained more attention. Despite several successes in modifying the ratio of endogenous fatty acids in most domesticated oilseed crops, numerous obstacles in FA manipulation of seed maturation are yet to be overcome. Remarkably, connections with plant hormones have not been well studied despite their critical roles in the regulation and promotion of a plethora of processes in plant growth and development. While activities of phytohormones during the reproductive phase have been partially clarified in seed physiology, the biological role of plant hormones in oil accumulation during seed development has not been investigated. In this review seed development and numerous effects of abiotic stresses are discussed. After describing fatty acid and phytohormone metabolism and their interactions, we postulate that the endogenous plant hormones play important roles in fatty acid production in soybean seeds.
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Affiliation(s)
- Quoc Thien. Nguyen
- Environmental & Life Sciences Graduate Program, Trent University, Peterborough, Ontario,Canada
| | - Anna Kisiala
- Department of Biology, Trent University, Peterborough, Ontario, Canada
| | - Peter Andreas
- Department of Biology, Trent University, Peterborough, Ontario, Canada
| | - R.J. Neil Emery
- Department of Biology, Trent University, Peterborough, Ontario, Canada
| | - Suresh Narine
- Trent Centre for Biomaterials Research, Departments of Physics & Astronomy and Chemistry, Trent University, Peterborough,Ontario, Canada
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Pospíšilová H, Jiskrová E, Vojta P, Mrízová K, Kokáš F, Čudejková MM, Bergougnoux V, Plíhal O, Klimešová J, Novák O, Dzurová L, Frébort I, Galuszka P. Transgenic barley overexpressing a cytokinin dehydrogenase gene shows greater tolerance to drought stress. N Biotechnol 2016; 33:692-705. [PMID: 26773738 DOI: 10.1016/j.nbt.2015.12.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 12/07/2015] [Accepted: 12/08/2015] [Indexed: 01/10/2023]
Abstract
Together with auxins, cytokinins are the main plant hormones involved in many different physiological processes. Given this knowledge, cytokinin levels can be manipulated by genetic modification in order to improve agronomic parameters of cereals in relation to, for example, morphology, yield, and tolerance to various stresses. The barley (Hordeum vulgare) cultivar Golden Promise was transformed using the cytokinin dehydrogenase 1 gene from Arabidopsis thaliana (AtCKX1) under the control of mild root-specific β-glucosidase promoter from maize. Increased cytokinin degradation activity was observed positively to affect the number and length of lateral roots. The impact on morphology depended upon the recombinant protein's subcellular compartmentation. While assumed cytosolic and vacuolar targeting of AtCKX1 had negligible effect on shoot growth, secretion of AtCKX1 protein to the apoplast had a negative effect on development of the aerial part and yield. Upon the application of severe drought stress, all transgenic genotypes maintained higher water content and showed better growth and yield parameters during revitalization. Higher tolerance to drought stress was most caused by altered root morphology resulting in better dehydration avoidance.
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Affiliation(s)
- Hana Pospíšilová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Eva Jiskrová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Petr Vojta
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 1333/5, 779 00 Olomouc, Czech Republic
| | - Katarína Mrízová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Filip Kokáš
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Mária Majeská Čudejková
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Veronique Bergougnoux
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Ondřej Plíhal
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Jana Klimešová
- Department of Crop Science, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
| | - Ondřej Novák
- Department of Metabolomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Lenka Dzurová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Petr Galuszka
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
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Yeh SY, Chen HW, Ng CY, Lin CY, Tseng TH, Li WH, Ku MSB. Down-Regulation of Cytokinin Oxidase 2 Expression Increases Tiller Number and Improves Rice Yield. RICE (NEW YORK, N.Y.) 2015; 8:36. [PMID: 26643073 PMCID: PMC4671980 DOI: 10.1186/s12284-015-0070-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 11/29/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND Cytokinins are plant-specific hormones that affect plant growth and development. The endogenous level of cytokinins in plant cells is regulated in part by irreversible degradation via cytokinin oxidase/dehydrogenase (CKX). Among the 11 rice CKXs, CKX2 has been implicated in regulation of rice grain yield. RESULTS To specifically down-regulate OsCKX2 expression, we have chosen two conserved glycosylation regions of OsCKX2 for designing artificial short hairpin RNA interference genes (shRNA-CX3 and -CX5, representing the 5' and 3' glycosylation region sequences, respectively) for transformation by the Agrobacterium-mediated method. For each construct, 5 independent transgenic lines were obtained for detailed analysis. Southern blot analysis confirmed the integration of the shRNA genes into the rice genome, and quantitative real time RT-PCR and northern blot analyses showed reduced OsCKX2 expression in the young stem of transgenic rice at varying degrees. However, the expression of other rice CKX genes, such as CKX1 and CKX3, in these transgenic lines was not altered. Transgenic rice plants grown in the greenhouse were greener and more vigorous with delayed senescence, compared to the wild type. In field experiments, both CX3 and CX5 transgenic rice plants produced more tillers (27-81 %) and grains (24-67 %) per plant and had a heavier 1000 grain weight (5-15 %) than the wild type. The increases in grain yield were highly correlated with increased tiller numbers. Consistently, insertional activation of OsCKX2 led to increased expression of CKX2 and reduced tiller number and growth in a gene-dosage dependant manner. CONCLUSIONS Taken together, these results demonstrate that specific suppression of OsCKX2 expression through shRNA-mediated gene silencing leads to enhanced growth and productivity in rice by increasing tiller number and grain weight.
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Affiliation(s)
- Su-Ying Yeh
- Biodiversity Research Center and Genome Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Hau-Wen Chen
- Department of Bioagricultural Science, National Chiayi University, Chiayi, 600, Taiwan
| | - Chun-Yeung Ng
- Biodiversity Research Center and Genome Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Chu-Yin Lin
- Biodiversity Research Center and Genome Research Center, Academia Sinica, Taipei, 115, Taiwan
| | - Tung-Hai Tseng
- Division of Biotechnology, Taiwan Agricultural Research Institute, Taichung, 413, Taiwan
| | - Wen-Hsiung Li
- Biodiversity Research Center and Genome Research Center, Academia Sinica, Taipei, 115, Taiwan
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, 60637, USA
| | - Maurice S B Ku
- Department of Bioagricultural Science, National Chiayi University, Chiayi, 600, Taiwan.
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA.
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Antimicrobial peptide production and plant-based expression systems for medical and agricultural biotechnology. Biotechnol Adv 2015; 33:1005-23. [DOI: 10.1016/j.biotechadv.2015.03.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 02/25/2015] [Accepted: 03/10/2015] [Indexed: 11/24/2022]
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Frébortová J, Greplová M, Seidl MF, Heyl A, Frébort I. Biochemical Characterization of Putative Adenylate Dimethylallyltransferase and Cytokinin Dehydrogenase from Nostoc sp. PCC 7120. PLoS One 2015; 10:e0138468. [PMID: 26376297 PMCID: PMC4574047 DOI: 10.1371/journal.pone.0138468] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/31/2015] [Indexed: 12/20/2022] Open
Abstract
Cytokinins, a class of phytohormones, are adenine derivatives common to many different organisms. In plants, these play a crucial role as regulators of plant development and the reaction to abiotic and biotic stress. Key enzymes in the cytokinin synthesis and degradation in modern land plants are the isopentyl transferases and the cytokinin dehydrogenases, respectively. Their encoding genes have been probably introduced into the plant lineage during the primary endosymbiosis. To shed light on the evolution of these proteins, the genes homologous to plant adenylate isopentenyl transferase and cytokinin dehydrogenase were amplified from the genomic DNA of cyanobacterium Nostoc sp. PCC 7120 and expressed in Escherichia coli. The putative isopentenyl transferase was shown to be functional in a biochemical assay. In contrast, no enzymatic activity was detected for the putative cytokinin dehydrogenase, even though the principal domains necessary for its function are present. Several mutant variants, in which conserved amino acids in land plant cytokinin dehydrogenases had been restored, were inactive. A combination of experimental data with phylogenetic analysis indicates that adenylate-type isopentenyl transferases might have evolved several times independently. While the Nostoc genome contains a gene coding for protein with characteristics of cytokinin dehydrogenase, the organism is not able to break down cytokinins in the way shown for land plants.
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Affiliation(s)
- Jitka Frébortová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Marta Greplová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Michael F. Seidl
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Alexander Heyl
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Berlin, Germany
| | - Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
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Tarkowská D, Novák O, Floková K, Tarkowski P, Turečková V, Grúz J, Rolčík J, Strnad M. Quo vadis plant hormone analysis? PLANTA 2014; 240:55-76. [PMID: 24677098 DOI: 10.1007/s00425-014-2063-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/08/2014] [Indexed: 05/04/2023]
Abstract
Plant hormones act as chemical messengers in the regulation of myriads of physiological processes that occur in plants. To date, nine groups of plant hormones have been identified and more will probably be discovered. Furthermore, members of each group may participate in the regulation of physiological responses in planta both alone and in concert with members of either the same group or other groups. The ideal way to study biochemical processes involving these signalling molecules is 'hormone profiling', i.e. quantification of not only the hormones themselves, but also their biosynthetic precursors and metabolites in plant tissues. However, this is highly challenging since trace amounts of all of these substances are present in highly complex plant matrices. Here, we review advances, current trends and future perspectives in the analysis of all currently known plant hormones and the associated problems of extracting them from plant tissues and separating them from the numerous potentially interfering compounds.
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Affiliation(s)
- Danuše Tarkowská
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany ASCR and Palacký University, Šlechtitelů 11, 783 71, Olomouc, Czech Republic,
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Suttle JC, Huckle LL, Lu S, Knauber DC. Potato tuber cytokinin oxidase/dehydrogenase genes: biochemical properties, activity, and expression during tuber dormancy progression. JOURNAL OF PLANT PHYSIOLOGY 2014; 171:448-57. [PMID: 24594397 DOI: 10.1016/j.jplph.2013.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 05/25/2023]
Abstract
The enzymatic and biochemical properties of the proteins encoded by five potato cytokinin oxidase/dehydrogenase (CKX)-like genes functionally expressed in yeast and the effects of tuber dormancy progression on StCKX expression and cytokinin metabolism were examined in lateral buds isolated from field-grown tubers. All five putative StCKX genes encoded proteins with in vitro CKX activity. All five enzymes were maximally active at neutral to slightly alkaline pH with 2,6-dichloro-indophenol as the electron acceptor. In silico analyses indicated that four proteins were likely secreted. Substrate dependence of two of the most active enzymes varied; one exhibiting greater activity with isopentenyl-type cytokinins while the other was maximally active with cis-zeatin as a substrate. [(3)H]-isopentenyl-adenosine was readily metabolized by excised tuber buds to adenine/adenosine demonstrating that CKX was active in planta. There was no change in apparent in planta CKX activity during either natural or chemically forced dormancy progression. Similarly although expression of individual StCKX genes varied modestly during tuber dormancy, there was no clear correlation between StCKX gene expression and tuber dormancy status. Thus although CKX gene expression and enzyme activity are present in potato tuber buds throughout dormancy, they do not appear to play a significant role in the regulation of cytokinin content during tuber dormancy progression.
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Affiliation(s)
- Jeffrey C Suttle
- U.S. Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, 1605 Albrecht Boulevard N, Fargo, ND 58102-2765, USA.
| | - Linda L Huckle
- U.S. Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, 1605 Albrecht Boulevard N, Fargo, ND 58102-2765, USA
| | - Shunwen Lu
- U.S. Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, 1605 Albrecht Boulevard N, Fargo, ND 58102-2765, USA
| | - Donna C Knauber
- U.S. Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, 1605 Albrecht Boulevard N, Fargo, ND 58102-2765, USA
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Zalabák D, Galuszka P, Mrízová K, Podlešáková K, Gu R, Frébortová J. Biochemical characterization of the maize cytokinin dehydrogenase family and cytokinin profiling in developing maize plantlets in relation to the expression of cytokinin dehydrogenase genes. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 74:283-93. [PMID: 24333683 DOI: 10.1016/j.plaphy.2013.11.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 11/19/2013] [Indexed: 05/18/2023]
Abstract
The cytokinin dehydrogenases (CKX; EC 1.5.99.12) are a protein family that maintains the endogenous levels of cytokinins in plants by catalyzing their oxidative degradation. The CKX family in maize (Zea mays L.) has thirteen members, only two of which--ZmCKX1 and ZmCKX10--have previously been characterized in detail. In this study, nine further maize CKX isoforms were heterologously expressed in Escherichia coli, purified by affinity and ion-exchange chromatography and biochemically characterized. ZmCKX6 and ZmCKX9 could only be expressed successfully after the removal of putative sequence-specific vacuolar sorting signals (LLPT and LPTS, respectively), suggesting that these proteins are localized to the vacuole. Substrate specificity analyses revealed that the CKX isoforms can be grouped into two subfamilies: members of the first strongly prefer cytokinin free bases while members of the second degrade a broad range of substrates. The most active isoform was found to be ZmCKX1. One of the studied isoforms, ZmCKX6, seemed to encode a nonfunctional enzyme due to a mutation in a conserved HFG protein domain at the C-terminus. Site-directed mutagenesis experiments revealed that this domain is essential for CKX activity. The roles of the maize CKX enzymes in the development of maize seedlings during the two weeks immediately after radicle emergence were also investigated. It appears that ZmCKX1 is a key regulator of active cytokinin levels in developing maize roots. However, the expression of individual CKX isoforms in the shoots varied and none of them seemed to have strong effects on the cytokinin pool.
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Affiliation(s)
- David Zalabák
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Molecular Biology, Šlechtitelů 11, Olomouc 783 71, Czech Republic.
| | - Petr Galuszka
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Molecular Biology, Šlechtitelů 11, Olomouc 783 71, Czech Republic.
| | - Katarina Mrízová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Molecular Biology, Šlechtitelů 11, Olomouc 783 71, Czech Republic.
| | - Kateřina Podlešáková
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Chemical Biology and Genetics, Šlechtitelů 11, Olomouc 783 71, Czech Republic.
| | - Riliang Gu
- Key Lab of Plant Nutrition, MOA, College of Resources and Environmental Science, China Agricultural University, 100193 Beijing, China.
| | - Jitka Frébortová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Chemical Biology and Genetics, Šlechtitelů 11, Olomouc 783 71, Czech Republic.
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Mrízová K, Jiskrová E, Vyroubalová Š, Novák O, Ohnoutková L, Pospíšilová H, Frébort I, Harwood WA, Galuszka P. Overexpression of cytokinin dehydrogenase genes in barley (Hordeum vulgare cv. Golden Promise) fundamentally affects morphology and fertility. PLoS One 2013; 8:e79029. [PMID: 24260147 PMCID: PMC3829838 DOI: 10.1371/journal.pone.0079029] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 09/17/2013] [Indexed: 01/07/2023] Open
Abstract
Barley is one of the most important cereal crops grown worldwide. It has numerous applications, but its utility could potentially be extended by genetically manipulating its hormonal balances. To explore some of this potential we identified gene families of cytokinin dehydrogenases (CKX) and isopentenyl transferases, enzymes that respectively irreversibly degrade and synthesize cytokinin (CK) plant hormones, in the raw sequenced barley genome. We then examined their spatial and temporal expression patterns by immunostaining and qPCR. Two CKX-specific antibodies, anti-HvCKX1 and anti-HvCKX9, predominantly detect proteins in the aleurone layer of maturing grains and leaf vasculature, respectively. In addition, two selected CKX genes were used for stable, Agrobacterium tumefaciens-mediated transformation of the barley cultivar Golden Promise. The results show that constitutive overexpression of CKX causes morphological changes in barley plants and prevents their transition to flowering. In all independent transgenic lines roots proliferated more rapidly and root-to-shoot ratios were higher than in wild-type plants. Only one transgenic line, overexpressing CKX under the control of a promoter from a phosphate transporter gene, which is expressed more strongly in root tissue than in aerial parts, yielded progeny. Analysis of several T1-generation plants indicates that plants tend to compensate for effects of the transgene and restore CK homeostasis later during development. Depleted CK levels during early phases of development are restored by down-regulation of endogenous CKX genes and reinforced de novo biosynthesis of CKs.
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Affiliation(s)
- Katarína Mrízová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Eva Jiskrová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Šárka Vyroubalová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulatory, Palacký University and Institute of Experimental Botany, Olomouc, Czech Republic
| | - Ludmila Ohnoutková
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Hana Pospíšilová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Wendy A. Harwood
- Department of Crop Genetics, John Innes Centre, Norwich, United Kingdom
| | - Petr Galuszka
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
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Černý M, Kuklová A, Hoehenwarter W, Fragner L, Novák O, Rotková G, Jedelský PL, Žáková K, Šmehilová M, Strnad M, Weckwerth W, Brzobohatý B. Proteome and metabolome profiling of cytokinin action in Arabidopsis identifying both distinct and similar responses to cytokinin down- and up-regulation. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:4193-206. [PMID: 24064926 PMCID: PMC3808309 DOI: 10.1093/jxb/ert227] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In plants, numerous developmental processes are controlled by cytokinin (CK) levels and their ratios to levels of other hormones. While molecular mechanisms underlying the regulatory roles of CKs have been intensely researched, proteomic and metabolomic responses to CK deficiency are unknown. Transgenic Arabidopsis seedlings carrying inducible barley cytokinin oxidase/dehydrogenase (CaMV35S>GR>HvCKX2) and agrobacterial isopentenyl transferase (CaMV35S>GR>ipt) constructs were profiled to elucidate proteome- and metabolome-wide responses to down- and up-regulation of CK levels, respectively. Proteome profiling identified >1100 proteins, 155 of which responded to HvCKX2 and/or ipt activation, mostly involved in growth, development, and/or hormone and light signalling. The metabolome profiling covered 79 metabolites, 33 of which responded to HvCKX2 and/or ipt activation, mostly amino acids, carbohydrates, and organic acids. Comparison of the data sets obtained from activated CaMV35S>GR>HvCKX2 and CaMV35S>GR>ipt plants revealed unexpectedly extensive overlaps. Integration of the proteomic and metabolomic data sets revealed: (i) novel components of molecular circuits involved in CK action (e.g. ribosomal proteins); (ii) previously unrecognized links to redox regulation and stress hormone signalling networks; and (iii) CK content markers. The striking overlaps in profiles observed in CK-deficient and CK-overproducing seedlings might explain surprising previously reported similarities between plants with down- and up-regulated CK levels.
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Affiliation(s)
- Martin Černý
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR and CEITEC–Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00 Brno, Czech Republic
| | - Alena Kuklová
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR and CEITEC–Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00 Brno, Czech Republic
| | - Wolfgang Hoehenwarter
- Department of Molecular Systems Biology (MOSYS), University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
- *Present address: Proteome Analysis Research Group, Leibniz Institute of Plant Biochemistry, D-06120 Halle, Germany
| | - Lena Fragner
- Department of Molecular Systems Biology (MOSYS), University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
| | - Ondřej Novák
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany, Academy of Sciences of the Czech Republic, CZ-78371 Olomouc, Czech Republic
| | - Gabriela Rotková
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR and CEITEC–Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00 Brno, Czech Republic
| | - Petr L. Jedelský
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, CZ-128 43 Prague, Czech Republic
| | - Kateřina Žáková
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR and CEITEC–Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00 Brno, Czech Republic
| | - Mária Šmehilová
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Molecular Biology, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-78371 Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany, Academy of Sciences of the Czech Republic, CZ-78371 Olomouc, Czech Republic
| | - Wolfram Weckwerth
- Department of Molecular Systems Biology (MOSYS), University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
| | - Břetislav Brzobohatý
- Laboratory of Plant Molecular Biology, Institute of Biophysics AS CR and CEITEC–Central European Institute of Technology, Mendel University in Brno, Zemědělská 1, CZ-613 00 Brno, Czech Republic
- To whom correspondence should be addressed. E-mail:
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Avalbaev AM, Somov KA, Yuldashev RA, Shakirova FM. Cytokinin oxidase is key enzyme of cytokinin degradation. BIOCHEMISTRY (MOSCOW) 2013; 77:1354-61. [PMID: 23244730 DOI: 10.1134/s0006297912120024] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cytokinin oxidase (EC 1.5.99.12) is an enzyme that catalyzes the irreversible degradation of cytokinin phytohormones that are extremely necessary for growth, development, and differentiation of plants. Cytokinin oxidase plays an important role in the regulation of quantitative level of cytokinins and their distribution in plant tissues. This review generalizes the available information on the structure, properties, and functional role of this enzyme in plant ontogeny under conditions of normal growth and under the influence of unfavorable environmental factors.
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Affiliation(s)
- A M Avalbaev
- Institute of Biochemistry and Genetics, Ufa Research Center of the Russian Academy of Sciences, pr. Oktyabrya 71, 450054 Ufa, Bashkortostan Republic, Russia
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Radchuk V, Radchuk R, Pirko Y, Vankova R, Gaudinova A, Korkhovoy V, Yemets A, Weber H, Weschke W, Blume YB. A somaclonal line SE7 of finger millet (Eleusine coracana) exhibits modified cytokinin homeostasis and increased grain yield. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:5497-506. [PMID: 22888132 PMCID: PMC3444265 DOI: 10.1093/jxb/ers200] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The SE7 somaclonal line of finger millet (Eleusine coracana) achieved increased grain yield in field trials that apparently resulted from a higher number of inflorescences and seeds per plant, compared with the wild type. Levels of endogenous cytokinins, especially those of highly physiologically active iso-pentenyl adenine, were increased during early inflorescence development in SE7 plants. Transcript levels of cytokinin-degrading enzymes but not of a cytokinin-synthesizing enzyme were also decreased in young leaves, seedlings, and initiating inflorescences of SE7. These data suggest that attenuated degradation of cytokinins in SE7 inflorescences leads to higher cytokinin levels that stimulate meristem activity and result in production of more inflorescences. Gene expression was compared between SE7 and wild-type young inflorescences using the barley 12K cDNA array. The largest fraction of up-regulated genes in SE7 was related to transcription, translation, and cell proliferation, cell wall assembly/biosynthesis, and to growth regulation of young and meristematic tissues including floral formation. Other up-regulated genes were associated with protein and lipid degradation and mitochondrial energy production. Down-regulated genes were related to pathogen defence and stress response, primary metabolism, glycolysis, and the C:N balance. The results indicate a prolonged proliferation phase in SE7 young inflorescences characterized by up-regulated protein synthesis, cytokinesis, floral formation, and energy production. In contrast, wild-type inflorescences are similar to a more differentiated status characterized by regulated protein degradation, cell elongation, and defence/stress responses. It is concluded that attenuated degradation of cytokinins in SE7 inflorescences leads to higher cytokinin levels, which stimulate meristem activity, inflorescence formation, and seed set.
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Affiliation(s)
- Volodymyr Radchuk
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstrasse 3, D-06466 Gatersleben, Germany.
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Franc V, Šebela M, Řehulka P, Končitíková R, Lenobel R, Madzak C, Kopečný D. Analysis of N-glycosylation in maize cytokinin oxidase/dehydrogenase 1 using a manual microgradient chromatographic separation coupled offline to MALDI-TOF/TOF mass spectrometry. J Proteomics 2012; 75:4027-37. [DOI: 10.1016/j.jprot.2012.05.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 04/13/2012] [Accepted: 05/08/2012] [Indexed: 12/26/2022]
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41
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Sp Chal LX. Cytokinins - recent news and views of evolutionally old molecules. FUNCTIONAL PLANT BIOLOGY : FPB 2012; 39:267-284. [PMID: 32480780 DOI: 10.1071/fp11276] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 03/06/2012] [Indexed: 05/03/2023]
Abstract
Cytokinins (CKs) are evolutionally old and highly conserved low-mass molecules that have been identified in almost all known organisms. In plants, they evolved into an important group of plant hormones controlling many physiological and developmental processes throughout the whole lifespan of the plant. CKs and their functions are, however, not unique to plants. In this review, the strategies and mechanisms of plants - and phylogenetically distinct plant-interacting organisms such as bacteria, fungi, nematodes and insects employing CKs or regulation of CK status in plants - are described and put into their evolutionary context. The major breakthroughs made in the last decade in the fields of CK biosynthesis, degradation and signalling are also summarised.
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Affiliation(s)
- Luk X Sp Chal
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-78371 Olomouc, Czech Republic. Email
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42
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Zalabák D, Pospíšilová H, Šmehilová M, Mrízová K, Frébort I, Galuszka P. Genetic engineering of cytokinin metabolism: prospective way to improve agricultural traits of crop plants. Biotechnol Adv 2011; 31:97-117. [PMID: 22198203 DOI: 10.1016/j.biotechadv.2011.12.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 12/02/2011] [Indexed: 01/02/2023]
Abstract
Cytokinins (CKs) are ubiquitous phytohormones that participate in development, morphogenesis and many physiological processes throughout plant kingdom. In higher plants, mutants and transgenic cells and tissues with altered activity of CK metabolic enzymes or perception machinery, have highlighted their crucial involvement in different agriculturally important traits, such as productivity, increased tolerance to various stresses and overall plant morphology. Furthermore, recent precise metabolomic analyses have elucidated the specific occurrence and distinct functions of different CK types in various plant species. Thus, smooth manipulation of active CK levels in a spatial and temporal way could be a very potent tool for plant biotechnology in the future. This review summarises recent advances in cytokinin research ranging from transgenic alteration of CK biosynthetic, degradation and glucosylation activities and CK perception to detailed elucidation of molecular processes, in which CKs work as a trigger in model plants. The first attempts to improve the quality of crop plants, focused on cereals are discussed, together with proposed mechanism of action of the responses involved.
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Affiliation(s)
- David Zalabák
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
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Kowalska M, Tian F, Šmehilová M, Galuszka P, Frébort I, Napier R, Dale N. Prussian Blue acts as a mediator in a reagentless cytokinin biosensor. Anal Chim Acta 2011; 701:218-23. [PMID: 21801891 DOI: 10.1016/j.aca.2011.06.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 04/19/2011] [Accepted: 06/15/2011] [Indexed: 10/18/2022]
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Cools K, Chope GA, Hammond JP, Thompson AJ, Terry LA. Ethylene and 1-methylcyclopropene differentially regulate gene expression during onion sprout suppression. PLANT PHYSIOLOGY 2011; 156:1639-52. [PMID: 21593215 PMCID: PMC3135958 DOI: 10.1104/pp.111.174979] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Onion (Allium cepa) is regarded as a nonclimacteric vegetable. In onions, however, ethylene can suppress sprouting while the ethylene-binding inhibitor 1-methylcyclopropene (1-MCP) can also suppress sprout growth; yet, it is unknown how ethylene and 1-MCP elicit the same response. In this study, onions were treated with 10 μL L(-1) ethylene or 1 μL L(-1) 1-MCP individually or in combination for 24 h at 20°C before or after curing (6 weeks) at 20°C or 28°C and then stored at 1°C. Following curing, a subset of these same onions was stored separately under continuous air or ethylene (10 μL L(-1)) at 1°C. Onions treated with ethylene and 1-MCP in combination after curing for 24 h had reduced sprout growth as compared with the control 25 weeks after harvest. Sprout growth following storage beyond 25 weeks was only reduced through continuous ethylene treatment. This observation was supported by a higher proportion of down-regulated genes characterized as being involved in photosynthesis, measured using a newly developed onion microarray. Physiological and biochemical data suggested that ethylene was being perceived in the presence of 1-MCP, since sprout growth was reduced in onions treated with 1-MCP and ethylene applied in combination but not when applied individually. A cluster of probes representing transcripts up-regulated by 1-MCP alone but down-regulated by ethylene alone or in the presence of 1-MCP support this suggestion. Ethylene and 1-MCP both down-regulated a probe tentatively annotated as an ethylene receptor as well as ethylene-insensitive 3, suggesting that both treatments down-regulate the perception and signaling events of ethylene.
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45
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Frébort I, Kowalska M, Hluska T, Frébortová J, Galuszka P. Evolution of cytokinin biosynthesis and degradation. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:2431-52. [PMID: 21321050 DOI: 10.1093/jxb/err004] [Citation(s) in RCA: 219] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cytokinin hormones are important regulators of development and environmental responses of plants that execute their action via the molecular machinery of signal perception and transduction. The limiting step of the whole process is the availability of the hormone in suitable concentrations in the right place and at the right time to interact with the specific receptor. Hence, the hormone concentrations in individual tissues, cells, and organelles must be properly maintained by biosynthetic and metabolic enzymes. Although there are merely two active cytokinins, isopentenyladenine and its hydroxylated derivative zeatin, a variety of conjugates they may form and the number of enzymes/isozymes with varying substrate specificity involved in their biosynthesis and conversion gives the plant a variety of tools for fine tuning of the hormone level. Recent genome-wide studies revealed the existence of the respective coding genes and gene families in plants and in some bacteria. This review summarizes present knowledge on the enzymes that synthesize cytokinins, form cytokinin conjugates, and carry out irreversible elimination of the hormones, including their phylogenetic analysis and possible variations in different organisms.
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Affiliation(s)
- Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 813/21, CZ-78371 Olomouc, Czech Republic.
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46
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Kowalska M, Galuszka P, Frébortová J, Šebela M, Béres T, Hluska T, Šmehilová M, Bilyeu KD, Frébort I. Vacuolar and cytosolic cytokinin dehydrogenases of Arabidopsis thaliana: heterologous expression, purification and properties. PHYTOCHEMISTRY 2010; 71:1970-8. [PMID: 20825956 DOI: 10.1016/j.phytochem.2010.08.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 07/20/2010] [Accepted: 08/11/2010] [Indexed: 05/08/2023]
Abstract
The catabolism of cytokinins is a vital component of hormonal regulation, contributing to the control of active forms of cytokinins and their cellular distribution. The enzyme catalyzing the irreversible cleavage of N(6)-side chains from cytokinins is a flavoprotein classified as cytokinin dehydrogenase (CKX, EC 1.5.99.12). CKXs also show low cytokinin oxidase activity, but molecular oxygen is a comparatively poor electron acceptor. The CKX gene family of Arabidopsis thaliana comprises seven members. Four code for proteins secreted to the apoplast, the remainder are not secreted. Two are targeted to the vacuoles and one is restricted to the cytosol. This study presents the purification and characterization of each of these non-secreted CKX enzymes and substrate specificities are discussed with respect to their compartmentation. Vacuolar enzymes AtCKX1 and AtCKX3 were produced in Pichia pastoris and cytosolic enzyme AtCKX7 was expressed in Escherichia coli. The recombinant proteins were purified by column chromatography. All enzymes preferred synthetic electron acceptors over oxygen, namely potassium ferricyanide and 2,3-dimetoxy-5-methyl-1,4-benzoquinone (Q(0)). In slightly acidic conditions (pH 5.0), N(6)-(2-isopentenyl)adenine 9-glucoside (iP9G) was the best substrate for AtCKX1 and AtCKX7, whereas AtCKX3 preferentially degraded N(6)-(2-isopentenyl)adenine 9-riboside-5'-monophosphate (iPMP). Moreover, vacuolar AtCKX enzymes in certain conditions degraded N(6)-(2-isopentenyl)adenine di- and triphosphates two to five times more effectively than its monophosphate.
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Affiliation(s)
- Marta Kowalska
- Department of Biochemistry, Faculty of Science, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
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Frébortová J, Novák O, Frébort I, Jorda R. Degradation of cytokinins by maize cytokinin dehydrogenase is mediated by free radicals generated by enzymatic oxidation of natural benzoxazinones. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 61:467-81. [PMID: 19912568 DOI: 10.1111/j.1365-313x.2009.04071.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Hydroxamic acid 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-one (DIMBOA) was isolated from maize phloem sap as a compound enhancing the degradation of isopentenyl adenine by maize cytokinin dehydrogenase (CKX), after oxidative conversion by either laccase or peroxidase. Laccase and peroxidase catalyze oxidative cleavage of DIMBOA to 4-nitrosoresorcinol-1-monomethyl ether (coniferron), which serves as a weak electron acceptor of CKX. The oxidation of DIMBOA and coniferron generates transitional free radicals that are used by CKX as effective electron acceptors. The function of free radicals in the CKX-catalyzed reaction was also verified with a stable free radical of 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid. Application of exogenous cytokinin to maize seedlings resulted in an enhanced benzoxazinoid content in maize phloem sap. The results indicate a new function for DIMBOA in the metabolism of the cytokinin group of plant hormones.
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Affiliation(s)
- Jitka Frébortová
- Laboratory of Growth Regulators, Faculty of Science, Palacký University/Institute of Experimental Botany of the Academy of Science, Slechtitelů 11, 783 71 Olomouc, Czech Republic.
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Kudo T, Kiba T, Sakakibara H. Metabolism and long-distance translocation of cytokinins. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2010; 52:53-60. [PMID: 20074140 DOI: 10.1111/j.1744-7909.2010.00898.x] [Citation(s) in RCA: 177] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
During plant development, distantly-located organs must communicate in order to adapt morphological and physiological features in response to environmental inputs. Among the recognized signaling molecules, a class of phytohormones known as the cytokinins functions as both local and long-distance regulatory signals for the coordination of plant development. This cytokinin-dependent communication system consists of orchestrated regulation of the metabolism, translocation, and signal transduction of this phytohormone class. Here, to gain insight into this elaborate signaling system, we summarize current models of biosynthesis, trans-membrane transport, and long-distance translocation of cytokinins in higher plants.
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Affiliation(s)
- Toru Kudo
- RIKEN Plant Science Center, Yokohama, Kanagawa, 230-0045, Japan
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Smehilová M, Galuszka P, Bilyeu KD, Jaworek P, Kowalska M, Sebela M, Sedlárová M, English JT, Frébort I. Subcellular localization and biochemical comparison of cytosolic and secreted cytokinin dehydrogenase enzymes from maize. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:2701-12. [PMID: 19436049 DOI: 10.1093/jxb/erp126] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cytokinin dehydrogenase (CKX; EC 1.5.99.12) degrades cytokinin hormones in plants. There are several differently targeted isoforms of CKX in plant cells. While most CKX enzymes appear to be localized in the apoplast or vacuoles, there is generally only one CKX per plant genome that lacks a translocation signal and presumably functions in the cytosol. The only extensively characterized maize CKX is the apoplastic ZmCKX1; a maize gene encoding a non-secreted CKX has not previously been cloned or characterized. Thus, the aim of this work was to characterize the maize non-secreted CKX gene (ZmCKX10), elucidate the subcellular localization of ZmCKX10, and compare its biochemical properties with those of ZmCKX1. Expression profiling of ZmCKX1 and ZmCKX10 was performed in maize tissues to determine their transcript abundance and organ-specific expression. For determination of the subcellular localization, the CKX genes were fused with green fluorescent protein (GFP) and overexpressed in tomato hairy roots. Using confocal microscopy, the ZmCKX1-GFP signal was confirmed to be present in the apoplast, whereas ZmCKX10-GFP was detected in the cytosol. No interactions of ZmCKX1 with the plasma membrane were observed. While roots overexpressing ZmCKX1-GFP formed significantly more mass in comparison with the control, non-secreted CKX overexpression resulted in a small reduction in root mass accumulation. Biochemical characterization of ZmCKX10 was performed using recombinant protein produced in Pichia pastoris. In contrast to the preference for 2,6-dichlorophenolindophenol (DCPIP) as an electron acceptor and trans-zeatin, N(6)-(Delta(2)-isopentenyl)adenine (iP) and N(6)-(Delta(2)-isopentenyl)adenosine (iPR) as substrates for ZmCKX1, the non-secreted ZmCKX10 had a range of suitable electron acceptors, and the enzyme had a higher preference for cis-zeatin and cytokinin N-glucosides as substrates.
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Affiliation(s)
- Mária Smehilová
- Department of Biochemistry, Faculty of Science, Palacký University, Slechtitelů 11, 78371 Olomouc, Czech Republic.
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Molecular cloning and expression analysis of a cytokinin oxidase (DhCKX) gene in Dendrobium huoshanense. Mol Biol Rep 2008; 36:1331-8. [DOI: 10.1007/s11033-008-9316-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 07/03/2008] [Indexed: 11/26/2022]
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