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Jin FC, Chen JJ, Xu QX, Zhou MH, Lin Y, Zhang QW, Zhang CC, Zhang ZG. Kinetin inhibits hepatic stellate cell activation and induces apoptosis via interactions with the TGF-β1/Smad signaling pathway. Toxicol Appl Pharmacol 2023; 475:116655. [PMID: 37579951 DOI: 10.1016/j.taap.2023.116655] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 07/22/2023] [Accepted: 08/11/2023] [Indexed: 08/16/2023]
Abstract
Hepatic fibrosis is the pathological repair response of the liver to chronic injury; hepatic stellate cell (HSC) activation is the central link in the pathogenesis of hepatic fibrosis. Previously, we showed that kinetin, a plant cytokinin hormone, has a protective effect on CCl4-induced liver injury in mice. However, the role of kinetin in liver fibrosis remains unclear. We aimed to study these protective effects and to determine the mechanisms by which kinetin mediates HSC activation and apoptosis. For this purpose, the human HSC line LX-2 was treated with 10 ng/ml transforming growth factor-β1 (TGF-β1) for 24 h to stimulate activation. We found that treatment with kinetin at the sub-cytotoxic dose of 40 μg/ml for 48 h reduced the expression of the HSC activation marker α-SMA and inhibited the secretion of extracellular matrix proteins. In addition, kinetin was found to inhibit the proliferation and migration of LX-2 cells. We found that kinetin induced apoptosis in LX-2 cells by increasing the level of cleaved-caspase 3 and the Bax-to-Bcl-2 ratio. Interestingly, these effect were not observed in quiescent HSCs, suggesting that they are activation-dependent. Further study showed that kinetin attenuates activation and promotes apoptosis of LX-2 cells in vitro in part by suppressing the TGF-β1/Smad signaling pathway.
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Affiliation(s)
- Fu-Chang Jin
- Division of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing-Jing Chen
- Division of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | | | - Ming-Hui Zhou
- Division of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Division of Gastroenterology, Tianyou Hospital, Wuhan University of Science and Technology, Wuhan, China
| | - Yi Lin
- Division of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi-Wei Zhang
- Jianghan University School of Medicine, Wuhan, China
| | - Chang-Chun Zhang
- Wuhan Sixth Hospital Affiliated to Jianghan University, Wuhan, China
| | - Zhen-Gang Zhang
- Division of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Guo LN, Lu L, Dong XR, Zhang FL, Yan P, Dong ZQ. Effects of gibberellic acid, kinetin and indole butyric acid mixture on sorghum salinity tolerance and grain yield in saline-alkali coastal zone. Ying Yong Sheng Tai Xue Bao 2023; 34:2405-2412. [PMID: 37899106 DOI: 10.13287/j.1001-9332.202309.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
The development and utilization of coastal saline-alkali lands hold significant importance in mitigating the shortage of cultivated land resources in China, enhancing the agro-ecological environment in coastal saline and alkaline areas, and ensuring national food security. We set up both pot and field trials (randomized block design) at Xinxiang experimental station of Institute of Crop Science, Chinese Academy of Agricultural Sciences (ICS-CAAS) and Dongying Yellow River Delta Modern Agricultural Research Base in Shandong Province in 2021 and 2022, respectively. The experimental materials, Jiliang 1 and Jiliang 2, underwent seed dressing with GKI composites at concentrations of 2.5 and 5 mL·kg-1. These composites, which contained the main components of gibberellin, kinetin, and indole butyric acid, were denoted as GKI2.5 and GKI5.0, respectively. The control plots (CK) received water seed dressing. The aim was to assess the regulatory effects of GKI on salt tolerance and grain sorghum yield. Compared to CK, the GKI2.5 and GKI5.0 seed dressing treatments significantly enhanced the growth and development of the two grain sorghum varieties, increased antioxidant enzyme activity and soluble protein content of sorghum leaves, while reducing leaf malondialdehyde content. Moreover, the GKI treatments increased leaf net photosynthetic rate. Under field conditions, yields of Jiliang 1 and Jiliang 2 were enhanced by an average of 17.1% and 19.1%, respectively. In conclusion, GKI seed dressing treatment effectively promoted the growth and development of sorghum under salt stress. It enhanced the antioxidant and osmoregulatory capacities of leaves, reduced the level of membrane lipid peroxidation, and improved net photosynthetic rate of leaves, which together improved the salt tolerance and sorghum yield.
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Affiliation(s)
- Li-Na Guo
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
- College of Agronomy, Agricultural University of Hebei, Baoding 071001, Hebei, China
| | - Lin Lu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
| | - Xue-Rui Dong
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
| | - Feng-Lu Zhang
- College of Agronomy, Agricultural University of Hebei, Baoding 071001, Hebei, China
| | - Peng Yan
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
| | - Zhi-Qiang Dong
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
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Vostálová J, Škařupová D, Plíhalová L, Hönig M, Zálešák B, Rajnochová Svobodová A. Photoprotective properties of new derivatives of kinetin. Photochem Photobiol Sci 2023; 22:357-369. [PMID: 36264480 DOI: 10.1007/s43630-022-00320-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 10/07/2022] [Indexed: 01/28/2023]
Abstract
The chronic exposure of skin to ultraviolet (UV) radiation causes adverse dermal reactions, such as erythema, sunburn, photoaging, and cancer, by altering several signalling pathways associated with oxidative stress, inflammation, and DNA damage. One of the possible UV light protection strategies is the use of dermal photoprotective preparations. The plant hormone kinetin (N6-furfuryladenine; KIN) exhibits antioxidant and anti-senescent effects in human cells. Topically applied KIN also reduced some of the clinical signs of photodamaged skin. To improve the biological activities of KIN, several derivatives have been recently prepared and their beneficial effects on cell viability of skin cells exposed to UVA and UVB light were screened. Two potent candidates, 6-(tetrahydrofuran-2-yl)methylamino-9-(tetrahydrofuran-2-yl)purine (HEO) and 6-(thiophen-2-yl)methylamino-9-(tetrahydrofuran-2-yl)purine (HEO6), were identified. Here the effects of KIN, its N9-substituted derivatives the tetrahydropyran-2-yl derivative of KIN (THP), tetrahydrofuran-2-yl KIN (THF), HEO and HEO6 (both THF derivatives) on oxidative stress, apoptosis and inflammation in UVA- or UVB-exposed skin cell was investigated. Human primary dermal fibroblasts and human keratinocytes HaCaT pre-treated with the tested compounds were then exposed to UVA/UVB light using a solar simulator. All compounds effectively prevented UVA-induced ROS generation and glutathione depletion in both cells. HEO6 was found to be the most potent. All compounds also reduced UVB-induced caspase-3 activity and interleukin-6 release. THP and THF exhibited the best UVB protection. In conclusion, our results demonstrated the UVA- and UVB-photoprotective potential of KIN and its derivatives. From this point of view, they seem to be useful agents for full UV spectrum protective dermatological preparations.
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Affiliation(s)
- Jitka Vostálová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15, Olomouc, Czech Republic
| | - Denisa Škařupová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15, Olomouc, Czech Republic
| | - Lucie Plíhalová
- Department of Chemical Biology, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany ASCR, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Martin Hönig
- Department of Chemical Biology, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Bohumil Zálešák
- Department of Plastic and Aesthetic Surgery, University Hospital Olomouc, I. P. Pavlova 6, 779 00, Olomouc, Czech Republic
| | - Alena Rajnochová Svobodová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15, Olomouc, Czech Republic.
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Abstract
Cell death (CD) may be induced by endogenous or exogenous factors and contributes to all the steps of plant development. This paper presents results related to the mechanism of CD regulation induced by kinetin (Kin) in the root cortex of Vicia faba ssp. minor. To explain the process, 6-(2-hydroxy-3-methylbenzylamino)purine (PI-55), adenine (Ad), 5'-amine-5'-deoxyadenosine (Ado) and N-(2-chloro-4-piridylo)-N'-phenylurea (CPPU) were applied to (i) block cytokinin receptors (CKs) and inhibit the activities of enzymes of CK metabolism, i.e., (ii) phosphoribosyltransferase, (iii) kinases, and (iv) oxidases, respectively. Moreover, ethylene glycol-bis(β-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), lanthanum chloride (LaCl3), ruthenium red (RRed) and cyclosporine A (CS-A) were applied to (i) chelate extracellular calcium ions (Ca2+) as well as blocks of (ii) plasma-, (iii) endoplasmic reticulum- (ER) membrane Ca2+ ion channels and (iv) mitochondria- (MIT) Ca2+ ions release by permeability transition por (PTP), respectively. The measured physiological effectiveness of these factors was the number of living and dying cortex cells estimated with orange acridine (OA) and ethidium bromide (EB), the amounts of cytosolic Ca2+ ions with chlortetracycline (CTC) staining and the intensity of chromatin and Ca2+-CTC complex fluorescence, respectively. Moreover, the role of sorafenib, an inhibitor of RAF kinase, on the vitality of cortex cells and ethylene levels as well as the activities of RAF-like kinase and MEK2 with Syntide-2 and Mek2 as substrates were studied. The results clarified the previously presented suggestion that Kin is converted to appropriate ribotides (5'-monophosphate ribonucleotides), which cooperate with the ethylene and Ca2+ ion signalling pathways to transduce the signal of kinetin-programmed cell death (Kin-PCD). Based on the present and previously published results related to Kin-PCD, the crosstalk between ethylene and MAP kinase signalling, as well as inhibitors of CK receptors and enzymes of their metabolism, is proposed.
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Affiliation(s)
- Andrzej Kaźmierczak
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland.
| | - Anita Kunikowska
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland
| | - Magdalena Doniak
- Department of Cytophysiology, Institute of Experimental Biology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Lodz, Poland
| | - Andrzej Kornaś
- Institute of Biology, Pedagogical University of Krakow, Podchorążych 2, 30-084, Kraków, Poland
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Bashri G, Singh S, Prasad SM, Ansari MJ, Usmani S, Alfarraj S, Alharbi SA, Brestic M. Kinetin mitigates Cd-induced damagesto growth, photosynthesis and PS II photochemistry of Trigonella seedlings by up-regulating ascorbate-glutathione cycle. PLoS One 2021; 16:e0249230. [PMID: 34157031 PMCID: PMC8219128 DOI: 10.1371/journal.pone.0249230] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 03/14/2021] [Indexed: 12/13/2022] Open
Abstract
Cytokinins (CKs) plays a key role in plant adaptation over a range of different stress conditions. Here, we analyze the effects of a cytokinin (i.e., kinetin, KN) on the growth, photosynthesis (rate of O2 evolution), PS II photochemistry and AsA-GSH cycle in Trigonella seedlings grown under cadmium (Cd) stress. Trigonella seeds were sown in soil amended with 0, 3 and 9 mg Cd kg-1 soil, and after 15 days resultant seedlings were sprayed with three doses of KN, i.e.,10 μM (low, KNL), 50 μM (medium, KNM) and 100 μM (high, KNH); subsequent experiments were performed after 15 days of KN application, i.e., 30 days after sowing. Cadmium toxicity induced oxidative damage as shown by decreased seedling growth and photosynthetic pigment production (Chl a, Chl b and Car), rates of O2-evolution, and photochemistry of PS II of Trigonella seedlings, all accompanied by an increase in H2O2 accumulation. Supplementation with doses of KN at KNL and KNM significantly improved the growth and photosynthetic activity by reducing H2O2 accumulation through the up-regulation AsA-GSH cycle. Notably, KNL and KNM doses stimulated the rate of enzyme activities of APX, GR and DHAR, involved in the AsA-GSH cycle thereby efficiently regulates the level of AsA and GSH in Trigonella grown under Cd stress. The study concludes that KN can mitigate the damaging effects of Cd stress on plant growth by maintaining the redox status (>ratios: AsA/DHA and GSH/GSSG) of cells through the regulation of AsA-GSH cycle at 10 and 50 μM KN under Cd stress conditions. At 100 μM KN, the down-regulation of AsA-GSH cycle did not support the growth and PS II activity of the test seedlings.
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Affiliation(s)
- Gausiya Bashri
- Department of Botany, Ranjan Plant Physiology and Biochemistry Laboratory, University of Allahabad, Allahabad, India
- * E-mail: (GB); (SMP); (MJA)
| | - Shikha Singh
- Department of Botany, Ranjan Plant Physiology and Biochemistry Laboratory, University of Allahabad, Allahabad, India
| | - Sheo Mohan Prasad
- Department of Botany, Ranjan Plant Physiology and Biochemistry Laboratory, University of Allahabad, Allahabad, India
- * E-mail: (GB); (SMP); (MJA)
| | - Mohammad Javed Ansari
- Department of Botany, Hindu College Moradabad, Mahatma Jyotiba Phule Rohilkhand University, Bareilly, India
- * E-mail: (GB); (SMP); (MJA)
| | - Salma Usmani
- Department of Biochemistry, D.K.M College for Women (Autonomous), Vellore, India
| | - Saleh Alfarraj
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Sulaiman Ali Alharbi
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Marian Brestic
- Department of Plant Physiology, Slovak University of Agriculture, Nitra, Slovakia
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Khan AL, Mabood F, Akber F, Ali A, Shahzad R, Al-Harrasi A, Al-Rawahi A, Shinwari ZK, Lee IJ. Endogenous phytohormones of frankincense producing Boswellia sacra tree populations. PLoS One 2018; 13:e0207910. [PMID: 30566477 PMCID: PMC6300221 DOI: 10.1371/journal.pone.0207910] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 11/08/2018] [Indexed: 12/17/2022] Open
Abstract
Boswellia sacra, an endemic tree to Oman, is exposed to man-made incisions for commercial level frankincense production, whereas unsustainable harvesting may lead to population decline. In this case, assessment of endogenous phytohormones (gibberellic acid (GA), indole-acetic acid (IAA), salicylic acid (SA) and kinetin) can help to understand population health and growth dynamics. Hence, it was aimed to devise a robust method using Near-Infrared spectroscopy (NIRS) coupled with multivariate methods for phytohormone analysis of thirteen different populations of B. sacra. NIRS data was recorded in absorption mode (10000-4000 cm-1) to build partial least squares regression model (calibration set 70%). Model was externally cross validated (30%) as a test set to check their prediction ability before the application to quantify the unknown amount of phytohormones in thirteen different populations of B. sacra. The results showed that phytohormonal contents varied significantly, showing a trend of SA>GA/IAA>kinetin across different populations. SA and GA contents were significantly higher in Pop13 (Hasik), followed by Pop2 (Dowkah)-an extreme end of B. sacra tree cover in Dhofar region. A similar trend in the concentration of phytohormones was found when the samples from 13 populations were subjected to advance liquid chromatography mass spectrophotometer and gas chromatograph with selected ion monitor analysis. The current analysis provides alternative tool to assess plant health, which could be important to in situ propagation of tree population as well as monitoring tree population growth dynamics.
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Affiliation(s)
- Abdul Latif Khan
- Natural & Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Fazal Mabood
- Department of Biological Sciences & Chemistry, University of Nizwa, Nizwa, Oman
| | - Fazal Akber
- Natural & Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Amjad Ali
- Natural & Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Raheem Shahzad
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Ahmed Al-Harrasi
- Natural & Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | - Ahmed Al-Rawahi
- Natural & Medical Sciences Research Center, University of Nizwa, Nizwa, Oman
| | | | - In-Jung Lee
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea
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Chen MS, Pan BZ, Wang GJ, Ni J, Niu L, Xu ZF. Analysis of the transcriptional responses in inflorescence buds of Jatropha curcas exposed to cytokinin treatment. BMC Plant Biol 2014; 14:318. [PMID: 25433671 PMCID: PMC4272566 DOI: 10.1186/s12870-014-0318-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 11/06/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Jatropha curcas L. is a potential biofuel plant. Application of exogenous cytokinin (6-benzyladenine, BA) on its inflorescence buds can significantly increase the number of female flowers, thereby improving seed yield. To investigate which genes and signal pathways are involved in the response to cytokinin in J. curcas inflorescence buds, we monitored transcriptional activity in inflorescences at 0, 3, 12, 24, and 48 h after BA treatment using a microarray. RESULTS We detected 5,555 differentially expressed transcripts over the course of the experiment, which could be grouped into 12 distinct temporal expression patterns. We also identified 31 and 131 transcripts in J. curcas whose homologs in model plants function in flowering and phytohormonal signaling pathways, respectively. According to the transcriptional analysis of genes involved in flower development, we hypothesized that BA treatment delays floral organ formation by inhibiting the transcription of the A, B and E classes of floral organ-identity genes, which would allow more time to generate more floral primordia in inflorescence meristems, thereby enhancing inflorescence branching and significantly increasing flower number per inflorescence. BA treatment might also play an important role in maintaining the flowering signals by activating the transcription of GIGANTEA (GI) and inactivating the transcription of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) and TERMINAL FLOWER 1b (TFL1b). In addition, exogenous cytokinin treatment could regulate the expression of genes involved in the metabolism and signaling of other phytohormones, indicating that cytokinin and other phytohormones jointly regulate flower development in J. curcas inflorescence buds. CONCLUSIONS Our study provides a framework to better understand the molecular mechanisms underlying changes in flowering traits in response to cytokinin treatment in J. curcas inflorescence buds. The results provide valuable information related to the mechanisms of cross-talk among multiple phytohormone signaling pathways in woody plants.
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Affiliation(s)
- Mao-Sheng Chen
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
- />University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Bang-Zhen Pan
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
| | - Gui-Juan Wang
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
| | - Jun Ni
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
- />School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 China
| | - Longjian Niu
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
- />School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 China
| | - Zeng-Fu Xu
- />Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Yunnan 666303 China
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Coelho N, González-Benito ME, Romano A. Approaches for the cryopreservation of Plantago algarbiensis, a rare endemic species of the Algarve. Cryo Letters 2014; 35:521-529. [PMID: 25583013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND Plantago algarbiensis is an endangered endemic species from the Algarve, Portugal. OBJECTIVE The main goal of this study was to investigate the viability of cryopreservation procedures in the conservation of seeds and nodal explants from this species. MATERIALS AND METHODS Seeds were directly immersed in liquid nitrogen (LN) for 30 days. Two methods were tested for the cryopreservation of nodal explants, namely droplet-vitrification and encapsulation-dehydration. For both methods, nodal segments were precultured on Murashige and Skoog (MS) medium and recovered on MS supplemented with 0.2 mg l(-1) 6-benzyladenine (BA), after freezing. RESULTS After 30 days in LN, the germination capacity of seeds was not affected. The regrowth percentages of cryopreserved nodal segments were approximately 60%. With the droplet-vitrification method, a regrowth percentage of 60.0+/-15.2% was obtained after 120 min exposure to PVS2 (plant vitrification solution 2) and with encapsulation-dehydration method the highest percentage, 63.3+/-9.6%, was achieved after 3 h desiccation. CONCLUSION Seed cryopreservation and cryopreservation of nodal segments by droplet-vitrification and encapsulation-dehydration are therefore effective approaches for the conservation of P. algarbiensis.
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Affiliation(s)
- Natacha Coelho
- Faculty of Sciences and Technology, MeditBio, University of Algarve, Campus de Gambelas, Faro, Portugal
| | | | - Anabela Romano
- Faculty of Sciences and Technology, MeditBio, University of Algarve, Campus de Gambelas, Faro, Portugal.
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Lu Y, Tarkowská D, Turečková V, Luo T, Xin Y, Li J, Wang Q, Jiao N, Strnad M, Xu J. Antagonistic roles of abscisic acid and cytokinin during response to nitrogen depletion in oleaginous microalga Nannochloropsis oceanica expand the evolutionary breadth of phytohormone function. Plant J 2014; 80:52-68. [PMID: 25041627 DOI: 10.1111/tpj.12615] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 07/06/2014] [Accepted: 07/07/2014] [Indexed: 05/03/2023]
Abstract
The origin of phytohormones is poorly understood, and their physiological roles in microalgae remain elusive. Genome comparison of photosynthetic autotrophic eukaryotes has revealed that the biosynthetic pathways of abscisic acid (ABA) and cytokinins (CKs) emerged in unicellular algae. While ABA and CK degradation mechanisms emerged broadly in algal lineages, complete vascular plant-type conjugation pathways emerged prior to the rise of Streptophyta. In microalgae, a complete set of proteins from the canonical ABA and CK sensing and signaling pathways is not essential, but individual components are present, suggesting stepwise recruitment of phytohormone signaling components. In the oleaginous eustigmatophyte Nannochloropsis oceanica IMET1, UHPLC-MS/MS detected a wide array of plant hormones, despite a phytohormone profile that is very distinct from that of flowering plants. Time-series transcriptional analysis during nitrogen depletion revealed activation of the ABA biosynthetic pathway and antagonistic transcription of CK biosynthetic genes. Correspondingly, the ABA level increases while the dominant bioactive CK forms decrease. Moreover, exogenous CKs stimulate cell-cycle progression while exogenous ABA acts as both an algal growth repressor and a positive regulator in response to stresses. The presence of such functional flowering plant-like phytohormone signaling systems in Nannochloropsis sp. suggests a much earlier origin of phytohormone biosynthesis and degradation than previously believed, and supports the presence in microalgae of as yet unknown conjugation and sensing/signaling systems that may be exploited for microalgal feedstock development.
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Affiliation(s)
- Yandu Lu
- Single Cell Center, Chinese Academy of Sciences Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong, 266101, China
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Migas P, Luczkiewicz M, Cisowski W. The Influence of Auxins on the Biosynthesis of Isoprene Derivatives in Callus Cultures of Vaccinium corymbosum var. bluecrop. Z NATURFORSCH C 2014; 61:565-70. [PMID: 16989318 DOI: 10.1515/znc-2006-7-816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Callus cultures of Vaccinium corymbosum var. bluecrop were optimized for their isoprene derivatives production by supplementing Schenk-Hildebrandt (SH) medium with constant concentration of kinetin (2.32 μᴍ) and two different amounts of selected auxins. Every auxin, except for IBA, used in 10-time higher concentration (2,4D, NAA, IAA, NOA) stimulated biosynthesis of β-sitosterol and inhibited triterpene synthesis. Quantitative analysis of isoprene derivatives in callus biomass collected on the 25th day of the experiment proved that the analyzed callus of Vaccinium corymbosum var. bluecrop synthesized the highest amount of isoprene derivatives after subculturing on SH medium modified with 22.6 μᴍ of 2,4D and 2.32 μᴍ of kinetin.
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Affiliation(s)
- Piotr Migas
- Department of Pharmacognosy, Medical University of Gdańsk, Al. Gen. J. Hallera 107, 80-416 Gdańsk-Wrzeszcz, Poland.
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Xu Q, Lu Y, Jing L, Cai L, Zhu X, Xie J, Hu X. Specific binding and inhibition of 6-benzylaminopurine to catalase: multiple spectroscopic methods combined with molecular docking study. Spectrochim Acta A Mol Biomol Spectrosc 2014; 123:327-335. [PMID: 24412785 DOI: 10.1016/j.saa.2013.12.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 12/05/2013] [Accepted: 12/05/2013] [Indexed: 06/03/2023]
Abstract
6-Benzylaminopurine (6-BA) is a kind of cytokinin which could regulate the activities of the antioxidant defense system of plants. In this work, its interaction with and inhibition of beef liver catalase have been systematically investigated using spectroscopic, isothermal titration calorimetric and molecular docking methods under physiological conditions. The fluorescence quenching of beef liver catalase (BLC) by 6-BA is due to the formation of 6-BA-BLC complex. Hydrogen bonds and van der Waals interactions play major roles in stabilizing the complex. The Stern-Volmer quenching constant, binding constant, the corresponding thermodynamic parameters and binding numbers were measured. The results of UV-vis absorption, three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopic results demonstrate that the binding of 6-BA results in the micro-environment change around tyrosine (Tyr) and tryptophan (Trp) residues of BLC. The BLC-mediated conversion of H2O2 to H2O and O2, in the presence and absence of 6-BA, was also studied. Lineweaver-Burk plot indicates a noncompetitive type of inhibition. Molecular docking study was used to find the binding sites.
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Affiliation(s)
- Qin Xu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | - Yanni Lu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Longyun Jing
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Lijuan Cai
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Xinfeng Zhu
- College of Information Technology, Yangzhou University, Yangzhou 225127, China
| | - Ju Xie
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Xiaoya Hu
- College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
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12
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Furet PM, Lothier J, Demotes-Mainard S, Travier S, Henry C, Guérin V, Vian A. Light and nitrogen nutrition regulate apical control in Rosa hybrida L. J Plant Physiol 2014; 171:7-13. [PMID: 24484952 DOI: 10.1016/j.jplph.2013.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/27/2013] [Accepted: 10/21/2013] [Indexed: 05/06/2023]
Abstract
Apical control is defined as the inhibition of basal axillary bud outgrowth by an upper actively growing axillary axis, whose regulation is poorly understood yet differs markedly from the better-known apical dominance. We studied the regulation of apical control by environmental factors in decapitated Rosa hybrida in order to remove the apical hormonal influence and nutrient sink. In this plant model, all the buds along the main axis have a similar morphology and are able to burst in vitro. We concentrated on the involvement of light intensity and nitrate nutrition on bud break and axillary bud elongation in the primary axis pruned above the fifth leaf of each rose bush. We observed that apical control took place in low light (92 μmol m(-2)s(-1)), where only the 2-apical buds grew out, both in low (0.25 mM) and high (12.25 mM) nitrate. In contrast, in high light (453 μmol m(-2)s(-1)), the apical control only operates in low nitrate while all the buds along the stem grew out when the plant was supplied with a high level of nitrate. We found a decreasing photosynthetic activity from the top to the base of the plant concomitant with a light gradient along the stem. The quantity of sucrose, fructose, glucose and starch are higher in high light conditions in leaves and stem. The expression of the sucrose transporter RhSUC2 was higher in internodes and buds in this lighting condition, suggesting an increased capacity for sucrose transport. We propose that light intensity and nitrogen availability both contribute to the establishment of apical control.
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Affiliation(s)
- Pierre-Maxime Furet
- Université d'Angers, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, PRES L'UNAM, 2 Bd Lavoisier, F-49045 Angers, France
| | - Jérémy Lothier
- Université d'Angers, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, PRES L'UNAM, 2 Bd Lavoisier, F-49045 Angers, France
| | - Sabine Demotes-Mainard
- INRA, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, BP 60057, F-49071 Beaucouzé, France
| | - Sandrine Travier
- Université d'Angers, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, PRES L'UNAM, 2 Bd Lavoisier, F-49045 Angers, France
| | - Clémence Henry
- Université d'Angers, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, PRES L'UNAM, 2 Bd Lavoisier, F-49045 Angers, France
| | - Vincent Guérin
- INRA, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, BP 60057, F-49071 Beaucouzé, France
| | - Alain Vian
- Université d'Angers, UMR 1345 Institut de Recherche en Horticulture et Semences (Université d'Angers, Agrocampus-Ouest, INRA), SFR 4207 QUASAV, PRES L'UNAM, 2 Bd Lavoisier, F-49045 Angers, France.
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13
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Marchi L, Degola F, Polverini E, Tercé-Laforgue T, Dubois F, Hirel B, Restivo FM. Glutamate dehydrogenase isoenzyme 3 (GDH3) of Arabidopsis thaliana is regulated by a combined effect of nitrogen and cytokinin. Plant Physiol Biochem 2013; 73:368-74. [PMID: 24189523 DOI: 10.1016/j.plaphy.2013.10.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/14/2013] [Indexed: 05/24/2023]
Abstract
In higher plants, NAD(H)-glutamate dehydrogenase (GDH; EC 1.4.1.2) is an abundant enzyme that exists in different isoenzymic forms. In Arabidopsis thaliana, three genes (Gdh1, Gdh2 and Gdh3) encode three different GDH subunits (β, α and γ) that randomly associate to form a complex array of homo- and heterohexamers. The modification of the GDH isoenzyme pattern and its regulation was studied during the development of A. thaliana in the gdh1, gdh2 single mutants and the gdh1-2 double mutant, with particular emphasis on GDH3. Investigations showed that the GDH3 isoenzyme could not be detected in closely related Arabidopsis species. The induction and regulation of GDH3 activity in the leaves and roots was investigated following nitrogen deprivation in the presence or absence of sucrose or kinetin. These experiments indicate that GDH3 is likely to play an important role during senescence and nutrient remobilization.
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Affiliation(s)
- Laura Marchi
- Dipartimento di Bioscienze, Università di Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
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14
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Ling APK, Tan KP, Hussein S. Comparative effects of plant growth regulators on leaf and stem explants of Labisia pumila var. alata. J Zhejiang Univ Sci B 2013; 14:621-31. [PMID: 23825148 PMCID: PMC3709067 DOI: 10.1631/jzus.b1200135] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 10/11/2012] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Labisia pumila var. alata, commonly known as 'Kacip Fatimah' or 'Selusuh Fatimah' in Southeast Asia, is traditionally used by members of the Malay community because of its post-partum medicinal properties. Its various pharmaceutical applications cause an excessive harvesting and lead to serious shortage in natural habitat. Thus, this in vitro propagation study investigated the effects of different plant growth regulators (PGRs) on in vitro leaf and stem explants of L. pumila. METHODS The capabilities of callus, shoot, and root formation were evaluated by culturing both explants on Murashige and Skoog (MS) medium supplemented with various PGRs at the concentrations of 0, 1, 3, 5, and 7 mg/L. RESULTS Medium supplemented with 3 mg/L indole-3-butyric acid (IBA) showed the optimal callogenesis from both leaf and stem explants with (72.34 ± 19.55)% and (70.40 ± 14.14)% efficacy, respectively. IBA was also found to be the most efficient PGR for root induction. A total of (50.00 ± 7.07)% and (77.78 ± 16.47)% of root formation were obtained from the in vitro stem and leaf explants after being cultured for (26.5 ± 5.0) and (30.0 ± 8.5) d in the medium supplemented with 1 and 3 mg/L of IBA, respectively. Shoot formation was only observed in stem explant, with the maximum percentage of formation ((100.00 ± 0.00)%) that was obtained in 1 mg/L zeatin after (11.0 ± 2.8) d of culture. CONCLUSIONS Callus, roots, and shoots can be induced from in vitro leaf and stem explants of L. pumila through the manipulation of types and concentrations of PGRs.
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Affiliation(s)
- Anna Pick Kiong Ling
- Division of Human Biology, International Medical University, 57000 Kuala Lumpur, Malaysia.
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15
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Silva LC, Paiva R, Swennen R, Andre E, Panis B. Shoot-tip cryopreservation by droplet vitrification of Byrsonima intermedia A. Juss.: a woody tropical and medicinal plant species from Brazilian cerrado. Cryo Letters 2013; 34:338-348. [PMID: 23995401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Cryopreservation of plant species is poorly investigated in Brazil. The aim of this study was to cryopreserve Byrsonima intermedia shoot apical meristems through droplet vitrification. A culture medium for shoot-tips growth was established using the Woody Plant Medium supplemented with 2.22 uM 6-benzylaminopurine. Excised shoot-tips were subjected to pre-culture and/or post-culture treatments on Murashige and Skoog medium with 0.3 M sucrose for 24 h prior dehydration on PVS2 at 0°C for 15, 30 or 45 minutes prior to plunging in liquid nitrogen. The effect of 15 days of shoot pre-growth on a high osmotic medium (0.3 M sucrose or 0.21 M sorbitol + 0.09 M sucrose) prior to meristem excision and cryopreservation was also investigated. Pre-culturing shoot-tips on 0.3 M sucrose for 24 h prior to cryopreservation increased the regrowth level after thawing to 90%. Shoot-tips excised from shoots pre-grown on MS + 0.21 M sorbitol + 0.09 M sucrose for 15 days presented a satisfactory regrowth level (67%).
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Affiliation(s)
- L C Silva
- Departamento de Biologia, Universidade Federal de Lavras, Brasil.
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16
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Ostrowski M, Jakubowska A. GH3 expression and IAA-amide synthetase activity in pea (Pisum sativum L.) seedlings are regulated by light, plant hormones and auxinic herbicides. J Plant Physiol 2013; 170:361-8. [PMID: 23332498 DOI: 10.1016/j.jplph.2012.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 10/05/2012] [Accepted: 10/22/2012] [Indexed: 05/14/2023]
Abstract
The formation of auxin conjugates is one of the important regulatory mechanisms for modulating IAA action. Several auxin-responsive GH3 genes encode IAA-amide synthetases that are involved in the maintenance of hormonal homeostasis by conjugating excess IAA to amino acids. Recently, the data have revealed novel regulatory functions of several GH3 proteins in plant growth, organ development, fruit ripening, light signaling, abiotic stress tolerance and plant defense responses. Indole-3-acetyl-aspartate (IAA-Asp) synthetase catalyzing IAA conjugation to aspartic acid in immature seeds of pea (Pisum sativum L.) was purified and characterized during our previous investigations. In this study, we examined the effect of auxin and other plant hormones (ABA, GA, kinetin, JA, MeJA, SA), different light conditions (red, far-red, blue, white light), and auxinic herbicides (2,4-D, Dicamba, Picloram) on the expression of a putative GH3 gene and IAA-amide synthesizing activity in 10-d-old pea seedlings. Quantitative RT-PCR analysis indicated that the PsGH3-5 gene, weakly expressed in control sample, was visibly induced in response to all plant hormones, different light wavelengths and the auxinic herbicides tested. Protein A immunoprecipitation/gel blot analysis using anti-AtGH3.5 antibodies revealed a similar pattern of changes on the protein levels in response to all treatments. IAA-amide synthetase activity determined with aspartate as a substrate, not detectable in control seedlings, was positively affected by a majority of treatments. Based on these results, we suggest that PsGH3-5 may control the growth and development of pea plants in a way similar to the known GH3 genes from other plant species.
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Affiliation(s)
- Maciej Ostrowski
- Department of Biochemistry, Nicolaus Copernicus University, Gagarina 9, 87-100 Toruń, Poland.
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17
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Žd'árská M, Zatloukalová P, Benítez M, Šedo O, Potěšil D, Novák O, Svačinová J, Pešek B, Malbeck J, Vašíčková J, Zdráhal Z, Hejátko J. Proteome analysis in Arabidopsis reveals shoot- and root-specific targets of cytokinin action and differential regulation of hormonal homeostasis. Plant Physiol 2013; 161:918-30. [PMID: 23209126 PMCID: PMC3561029 DOI: 10.1104/pp.112.202853] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The plant hormones cytokinins (CKs) regulate multiple developmental and physiological processes in Arabidopsis (Arabidopsis thaliana). Responses to CKs vary in different organs and tissues (e.g. the response to CKs has been shown to be opposite in shoot and root samples). However, the tissue-specific targets of CKs and the mechanisms underlying such specificity remain largely unclear. Here, we show that the Arabidopsis proteome responds with strong tissue and time specificity to the aromatic CK 6-benzylaminopurine (BAP) and that fast posttranscriptional and/or posttranslational regulation of protein abundance is involved in the contrasting shoot and root proteome responses to BAP. We demonstrate that BAP predominantly regulates proteins involved in carbohydrate and energy metabolism in the shoot as well as protein synthesis and destination in the root. Furthermore, we found that BAP treatment affects endogenous hormonal homeostasis, again with strong tissue specificity. In the shoot, BAP up-regulates the abundance of proteins involved in abscisic acid (ABA) biosynthesis and the ABA response, whereas in the root, BAP rapidly and strongly up-regulates the majority of proteins in the ethylene biosynthetic pathway. This was further corroborated by direct measurements of hormone metabolites, showing that BAP increases ABA levels in the shoot and 1-aminocyclopropane-1-carboxylic acid, the rate-limiting precursor of ethylene biosynthesis, in the root. In support of the physiological importance of these findings, we identified the role of proteins mediating BAP-induced ethylene production, METHIONINE SYNTHASE1 and ACC OXIDASE2, in the early root growth response to BAP.
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18
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Nguyen KT, Towler MJ, Weathers PJ. The effect of roots and media constituents on trichomes and artemisinin production in Artemisia annua L. Plant Cell Rep 2013; 32:207-18. [PMID: 23085820 PMCID: PMC3551342 DOI: 10.1007/s00299-012-1355-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 09/20/2012] [Accepted: 10/07/2012] [Indexed: 05/21/2023]
Abstract
KEY MESSAGE : Rooting of Artemisia annua increases trichome size on leaves and helps drive the final steps of the biosynthesis of the sesquiterpene antimalarial drug, artemisinin. Artemisia annua produces the antimalarial drug, artemisinin (AN), which is synthesized and stored in glandular trichomes (GLTs). In vitro-grown A. annua shoots produce more AN when they form roots. This may be a function not of the roots, but rather media components such as the phytohormones, α-naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP), or salts and sucrose used to maintain either rooted or unrooted shoot cultures. We investigated how three main media components altered artemisinic metabolite production, pathway gene transcripts, and GLT formation in both mature and developing leaves in rooted and unrooted cultures. Although transcript levels of AN biosynthetic genes were not altered, AN levels were significantly different, and there were major differences in both artemisinic metabolite levels and trichomes in mature versus developing leaves. For example, NAA induced higher AN production in rooted shoots, but only in mature leaves. In developing leaves, BAP increased GLT density on the leaf surface. When both phytohormones were present, GLTs were larger on young developing leaves, but smaller on mature leaves. Furthermore, although other media components increased GLT density, their size decreased on young leaves, but there was no effect on mature leaves. Roots also appeared to drive conversion of artemisinic precursors towards end products. These results suggest that, while the presence of roots affects AN and trichome production, phytohormones and other media constituents used for in vitro culture of A. annua also exert an influence.
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19
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Hong SR, Yin MH. High-efficiency encapsulation-vitrification protocols for cryopreservation of embryogenic calli of the oriental medicinal plant Anemarrhena asphodeloides Bunge. Cryo Letters 2012; 33:191-201. [PMID: 22825786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Embryogenic calli from in vitro grown tillers of Anemarrhena asphodeloides Bunge were successfully cryopreserved by the encapsulation-vitrification technique. Excised embryogenic calli were precultured for 4 days in liquid MS medium supplemented with 2 mg per liter kinetin (KIN), 0.1 mg per liter α-naphthalene acetic acid (NAA) and 0.75 M sucrose, then encapsulated in calcium alginate beads and loaded with a mixture of 2 M glycerol + 0.4 M sucrose for 60 min at 25 +/- 1 degree C. Calli were then dehydrated with the PVS2 solution for 80 min at 0 degree C. After changing the solution with fresh PVS2, calli were directly immersed in liquid nitrogen (LN). After rapid rewarming in a water-bath at 35 degree C for 5 min, calli were washed three times with liquid MS medium supplemented with 2 mg L-1 KIN, 0.1 mg per liter NAA and 1.2 M sucrose, then transferred on solid MS medium supplemented with 2 mg per liter KIN, 0.1 mg per liter NAA, 3 % (w/v) sucrose and 0.75 % (w/v) agar. Cryopreserved cultures were kept in the dark for 5 days prior to exposure to a 14h light/10h dark photoperiod with a light intensity of 36 μmol per square meter per sec provided by white cool fluorescent tubes at 25 +/- 1 degree C. Survival of cryopreserved embryogenic calli reached 80 percent, including after storage for c. 1 year. No significant difference was observed in the morphological development of plants coming from control and cryopreserved embryogenic calli. This encapsulation-vitrification method appears promising for the cryopreservation of A. asphodeloides Bunge germplasm.
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Affiliation(s)
- S-R Hong
- College of Life Sciences, Shangrao Normal University, Shangrao, China
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20
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Lukaszewska E, Virden R, Sliwinska E. Hormonal control of endoreduplication in sugar beet (Beta vulgaris L.) seedlings growing in vitro. Plant Biol (Stuttg) 2012; 14:216-222. [PMID: 21973015 DOI: 10.1111/j.1438-8677.2011.00477.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The effect on endoreduplication in sugar beet (Beta vulgaris L.) seedlings of five plant hormones in MS medium, ethylene, 24-epibrassinolide (EBR), gibberellic acid (GA(3) ), kinetin and 1-naphthaleneacetic acid (NAA), as well as a combination of kinetin and NAA at two different concentrations, was studied using flow cytometry. Analyses of DNA content in nuclei of the root, hypocotyl and cotyledons of seedlings growing in vitro were performed during their early development, starting from when the root was 0.5-1.0 cm long until expansion of the first pair of leaves. The proportions of nuclei with different DNA contents were established and the mean C-value calculated. The presence of exogenous plant hormones changed endoreduplication intensity, although to different extents, depending on the organ and developmental stage. Ethylene and NAA stimulated the process, while EBR and kinetin suppressed it and GA did not clearly affect it.
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Affiliation(s)
- E Lukaszewska
- Laboratory of Molecular Biology and Cytometry, Department of Plant Genetics and Biotechnology, University of Technology and Life Sciences, Bydgoszcz, Poland
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21
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Davidiants ES. [Effect of triterpenoid glycosides on alpha- and beta-amylase activity and total protein content in wheat seedlings]. Prikl Biokhim Mikrobiol 2011; 47:530-536. [PMID: 22232893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Influence of the aleanolic acid glycosides from Silphium perfoliatum L. (silphioside B, C, E and G) and their progenins on the amylase activity and total protein content in wheat seedlings was studied. Treatment of the Triticum aestivum L. seeds with 1-10 microM water solutions of mono- and diglycosides (mono- and bisdesmosines) elevated the alpha-amylase and total amylase activities in seedlings. Silphioside E containing three glucose moieties in its molecule did not change alpha-amylase activity, but it did if bis-triglycoside acetylated carbohydrate (as in silphioside C). Effects of 5-10 microM solutions of the active glycosides was comparable with that of exogenous gibberellin A3 and 6-benzylaminopurine.
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22
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Zhao Y, Peralta-Videa JR, Lopez-Moreno ML, Ren M, Saupe G, Gardea-Torresdey JL. Kinetin increases chromium absorption, modulates its distribution, and changes the activity of catalase and ascorbate peroxidase in Mexican Palo Verde. Environ Sci Technol 2011; 45:1082-7. [PMID: 21174467 PMCID: PMC4337997 DOI: 10.1021/es102647w] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
This report shows, for the first time, the effectiveness of the phytohormone kinetin (KN) in increasing Cr translocation from roots to stems in Mexican Palo Verde. Fifteen-day-old seedlings, germinated in soil spiked with Cr(III) and (VI) at 60 and 10 mg kg(-1), respectively, were watered every other day for 30 days with a KN solution at 250 μM. Samples were analyzed for catalase (CAT) and ascorbate peroxidase (APOX) activities, Cr concentration, and Cr distribution in tissues. Results showed that KN reduced CAT but increased APOX in the roots of Cr(VI)-treated plants. In the leaves, KN reduced both CAT and APOX in Cr(III) but not in Cr(VI)-treated plants. However, KN increased total Cr concentration in roots, stems, and leaves by 45%, 103%, and 72%, respectively, compared to Cr(III) alone. For Cr(VI), KN increased Cr concentrations in roots, stems, and leaves, respectively, by 53%, 129%, and 168%, compared to Cr(VI) alone. The electron probe microanalyzer results showed that Cr was mainly located at the cortex section in the root, and Cr distribution was essentially homogeneous in stems. However, proven through X-ray images, Cr(VI)-treated roots and stems had more Cr accumulation than Cr(III) counterparts. KN increased the Cr translocation from roots to stems.
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Affiliation(s)
- Yong Zhao
- Department of Chemistry, The University of Texas at El Paso, El Paso, TX 79968, USA
| | | | - Martha L. Lopez-Moreno
- Department of Chemistry, The University of Texas at El Paso, El Paso, TX 79968, USA
- Department of Chemistry, University of Puerto Rico at Mayaguez, Mayaguez, PR, 00681
| | - Minghua Ren
- Department of Geology, The University of Texas at El Paso, El Paso, TX 79968, USA
| | - Geoffrey Saupe
- Department of Chemistry, The University of Texas at El Paso, El Paso, TX 79968, USA
| | - Jorge L Gardea-Torresdey
- Department of Chemistry, The University of Texas at El Paso, El Paso, TX 79968, USA
- Environmental Science and Engineering Ph.D. Program, The University of Texas at El Paso, El Paso, TX 79968, USA
- Corresponding Author: To whom all correspondence should be addressed phone: (915)747-5359, Fax: (915) 747-5748,
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Zhang H, Horgan KJ, Reynolds PHS, Jameson PE. 6-benzyladenine metabolism during reinvigoration of mature Pinus radiata buds in vitro. Tree Physiol 2010; 30:514-26. [PMID: 20144924 DOI: 10.1093/treephys/tpp130] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Maturation or phase change is a serious challenge in the deployment of superior trees of Pinus radiata D. Don because of the difficulties associated with propagation of cuttings from mature trees. We used an in vitro system to study 6-benzyladenine (BA)-induced reinvigoration of the fascicle meristems of mature buds during in vitro culture. Anatomical examinations revealed that BA inhibited the development of secondary needle primordia and 'rejuvenated' the fascicle meristems of the mature bud to produce primary needles, which are characteristic of the juvenile phase in P. radiata. Without BA supplement in the culture media, fascicle primordia continued developing secondary needles and quiescent fascicle meristems. BA metabolite analysis showed that the novel cytokinin pathway reported previously in P. radiata (H. Zhang, K.J. Horgan, P.H.S. Reynolds, G.E. Norris and P.E. Jameson. 2001. Novel cytokinins: The predominant forms in mature buds of Pinus radiata. Physiol. Plant. 112: 127-134) was mirrored in vitro, with BA converted into a variety of metabolites including 6-benzylamino-9-glucopyranosylribosyl-purine and its novel phosphorylated form, 6-benzylamino-9-glucopyranosylribosyl-purine. The culture of mature buds in the presence of BA caused a reduction in the level of endogenous cytokinins, suggesting a direct action of BA itself. Similar correlations are noted between levels of certain metabolites and the maturation status of buds from field-grown trees and buds in culture, indicating that this in vitro system may be a good model for studying the processes of maturation and reinvigoration.
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Affiliation(s)
- Huaibi Zhang
- New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North, New Zealand
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Zhang F, Guo S. [Application of SPSS orthogonal design in tissue culture of Anoectochilus roxburghii]. Zhongguo Zhong Yao Za Zhi 2009; 34:2581-2585. [PMID: 20069896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To study the effect of the different constitutions of plant hormone on the development of Anoectochilus roxburghii. METHOD A. roxburghii were harvested after having been cultured for 60 days. An orthogonal design was used to study the effect of NAA and 6-BA on the leaf number, eustipe number, lateral branch number of the stem tip and stem section, and the height of the stem tips. All of the data were processed by SPSS. RESULT AND CONCLUSION It is reported for the first time that NAA could make different development of A. roxburghii at low concentration ( < 1 mg L(-1)) and high concentration ( > 1 mg L(-1)). The optimum constitution of MS medium was NAA 0.5 mg L(-1) + 6-BA 1 mg L(-1) for the growth of the stem tip of A. roxburghii, and NAA 1 mg L(-1) + 6-BA 2 mg L(-1) for the differentiation of bud and the formation of lateral branch of the stem section. The different concentrations of NAA and 6-BA had different effects on the growth and differentiation of the stem tip and the stem section of A. roxburghii.
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Affiliation(s)
- Fusheng Zhang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Sobieszczuk-Nowicka E, Wieczorek P, Legocka J. Kinetin affects the level of chloroplast polyamines and transglutaminase activity during senescence of barley leaves. Acta Biochim Pol 2009; 56:255-259. [PMID: 19436838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 03/25/2009] [Accepted: 05/05/2009] [Indexed: 05/27/2023]
Abstract
We analysed the level of polyamines (PAs) bound to thylakoids and the level and activity of thylakoid transglutaminases throughout barley leaf senescence, retarded by kinetin. The level of PAs bound to thylakoids changed in senescing barley leaves: bound putrescine (PU) and spermidine (SD) increased throughout senescence, whereas bound spermine (SM) decreased. Kinetin diminished the increase in thylakoid-bound PU and SD and almost completely abolished the decrease of the bound SM. These data suggest different roles of PU/SD and SM in thylakoid degradation. Immunodetection of transglutaminases (TGase) in thylakoid fraction revealed three bands of 33, 58 and 78 kDa. During senescence the intensity of all bands increased and it was correlated with an increase in TGase activity. Kinetin down-regulated the accumulation of the 58- and 78-kDa TGases and the TGase activity. We postulate that formation of covalent bonds between PAs and proteins by TGase is involved in chloroplast senescence. The kinetin-mediated preservation of low TGase levels and activity throughout leaf senescence may represent an important component of the mechanism of kinetin action in the retardation of leaf senescence.
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Affiliation(s)
- Ewa Sobieszczuk-Nowicka
- Department of Plant Physiology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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26
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Abstract
Melatonin (N-acetyl-5-methoxytryptamine) is a highly conserved molecule whose presence is not exclusive to the animal kingdom. Indeed, numerous studies have demonstrated its presence in plants, where the possible role(s) of this indoleamine is (are) under active investigation. The present work aims to further our knowledge in this respect and presents the results of a study of the effect that melatonin has on foliar senescence. Barley leaves treated with melatonin solutions clearly slowed down the senescence process, as estimated from the chlorophyll lost in leaves. This effect of melatonin was concentration dependent, with an optimal response being obtained at 1 mm melatonin, after 48 hr of incubation in darkness. The already known effects of the phytohormones, kinetin, and abscisic acid, were also assayed. Of the phytohormone and melatonin combinations assayed, 1 mm melatonin presented the best protection against senescence. The levels of endogenous melatonin in control leaves were measured by liquid chromatography with fluorescence detection and in leaves treated with different exogenous melatonin concentrations (to demonstrate the absorption capacity of leaves). The possible physiological implications of this newly revealed action of melatonin in foliar senescence are discussed.
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Affiliation(s)
- M B Arnao
- Faculty of Biology, Department of Plant Physiology, University of Murcia, Murcia, Spain.
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Abstract
Cytokinins are important adenine derivatives that serve as hormones to control many processes in plants. They were discovered as factors that promote cell division in tobacco tissue cultures and have been shown also to regulate several other developmental events. Kinetin which was isolated 50 years ago for the first time as a plant hormone, as well as other cytokinins isopentenyladenine, zeatin and benzylaminopurine induce callus (clusters of dedifferentiated plant cells) to redifferentiate into adventitious buds. Because of some similarities in the biological phenotypes of cancer and callus cells, cytokinins and especially kinetin, affect the differentiation of human cells through a common signal transduction system. Therefore, cytokinins found their way to use in molecular medicine.
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Affiliation(s)
- Jan Barciszewski
- Institute of Bioorganic Chemistry of the Polish Academy of Sciences, Noskowskiego 12, 61-704 Poznan, Poland.
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Rup PJ, Sohal SK, Kaur H. Studies on the role of six enzymes in the metabolism of kinetin in mustard aphid, Lipaphis erysimi (Kalt.). J Environ Biol 2006; 27:579-84. [PMID: 17402253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The activity of catalase, glutathione peroxidase, superoxide dismutase, O-demethylase, ATPase and succinate dehydrogenase, belonging to two main classes of detoxification enzymes (i.e. hydrolases and oxido-reductases), mostly involved in metabolism and degradation of xenobiotics in insects, were assessed under the influence of kinetin, a plant growth regulator (PGR). The nymphs (48-52 hr old) of Lipaphis erysimi (Kalt.) were permitted to feed on radish plant, Raphanus sativus L. treated with kinetin (400 ppm) for 13, 25 and 37 hr. It was found that the activity of catalase, glutathione peroxidase and superoxide dismutase increased significantly when compared with the control of the same age group, which indicated that these enzymes might be playing a significant role in the metabolism of kinetin in this insect. The activity of O-demethylase showed an increase up to 25 hr of the treatment but it decreased under prolonged treatment whereas the activity of succinate dehydrogenase fluctuated insignificantly. ATPase showed a decrease in the activity with the treatment suggesting kinetin's interference in synthesis of ATPase.
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Affiliation(s)
- Pushpinder J Rup
- Department of Zoology, Guru Nanak Dev University, Amritsar-143 005, India.
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Mähönen AP, Bishopp A, Higuchi M, Nieminen KM, Kinoshita K, Törmäkangas K, Ikeda Y, Oka A, Kakimoto T, Helariutta Y. Cytokinin signaling and its inhibitor AHP6 regulate cell fate during vascular development. Science 2006; 311:94-8. [PMID: 16400151 DOI: 10.1126/science.1118875] [Citation(s) in RCA: 384] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The cell lineages that form the transporting tissues (xylem and phloem) and the intervening pluripotent procambial tissue originate from stem cells near the root tip. We demonstrate that in Arabidopsis, cytokinin phytohormones negatively regulate protoxylem specification. AHP6, an inhibitory pseudophosphotransfer protein, counteracts cytokinin signaling, allowing protoxylem formation. Conversely, cytokinin signaling negatively regulates the spatial domain of AHP6 expression. Thus, by controlling the identity of cell lineages, the reciprocal interaction of cytokinin signaling and its spatially specific modulator regulates proliferation and differentiation of cell lineages during vascular development, demonstrating a previously unrecognized regulatory circuit underlying meristem organization.
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Affiliation(s)
- Ari Pekka Mähönen
- Plant Molecular Biology Laboratory, Institute of Biotechnology, POB 56, FI-00014, University of Helsinki, Finland
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Koistinen KM, Soininen P, Venäläinen TA, Häyrinen J, Laatikainen R, Peräkylä M, Tervahauta AI, Kärenlampi SO. Birch PR-10c interacts with several biologically important ligands. Phytochemistry 2005; 66:2524-33. [PMID: 16246382 DOI: 10.1016/j.phytochem.2005.09.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Revised: 09/01/2005] [Accepted: 09/12/2005] [Indexed: 05/05/2023]
Abstract
PR-10c is a unique member of PR-10 proteins in birch, since it is the only one known to be post-translationally modified by glutathione and is not constitutively expressed in pollen. Both reduced and S-glutathiolated forms of PR-10c show low ribonuclease activity. However, the major function of the protein is apparently not yet resolved. Our protein-ligand interaction studies with saturation transfer difference (STD) NMR revealed that PR-10c interacts with several biologically important molecules, including cytokinin, flavonoid glycosides, sterols and emodin. Competition study with deoxycholate and kinetin revealed no statistically significant binding interference, indicating that these ligands have different binding sites in PR-10c. Ligand docking studies with a molecular model of PR-10c support the STD NMR results of ligand binding and binding epitopes, suggesting that there are three potential binding sites in PR-10c: two in the hydrophobic cavity and one in the glycine-rich loop. Our docking calculations suggested that only kinetin interacts with the glycine-rich loop, the binding occurring through its adenine moiety. Clear ligand specificity could be observed in the binding of nucleotide derivatives. S-glutathiolation of PR-10c did not affect kinetin binding. The present results suggest that birch PR-10c is a multifunctional protein, which has diverse roles in plant stress responses.
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Affiliation(s)
- Kaisa M Koistinen
- Institute of Applied Biotechnology, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland
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Moncaleán P, Alonso P, Centeno ML, Cortizo M, Rodríguez A, Fernández B, Ordás RJ. Organogenic responses of Pinus pinea cotyledons to hormonal treatments: BA metabolism and cytokinin content. Tree Physiol 2005; 25:1-9. [PMID: 15519980 DOI: 10.1093/treephys/25.1.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Isolated cotyledons from mature Pinus pinea L. embryos were cultured in vitro in a factorial combination of 4.4, 10 and 44.4 microM N6-benzyladenine (BA) for 2, 4, 8, 16 and 35 days to optimize shoot regeneration. Incubation of explants in 44.4 microM BA for 4 days, in place of the standard incubation in 4.4 microM BA for 35 days, reduced the entire culture period to 4 weeks. Shortening the culture period had no significant effect on the caulogenic response or the number of buds formed per cotyledon. To establish the relationship between key moments in the caulogenic process induced by 4.4 microM BA and the endogenous concentrations of the active forms of BA and other isoprenoid-type cytokinins (CKs), we examined uptake, metabolism and amount of BA, as well as the amounts of zeatin, dihydrozeatin and their ribosides in P. pinea cotyledons after 1, 2, 6, 12 and 24 h, and 2, 4, 8, 16 and 35 days of exposure to 8-[14C]BA. Uptake and release of BA were associated with water movement between explants and the medium during the first 8 days of culture. The interconvertible forms of BA were the main metabolites formed in the tissues. Inactivation of BA as a result of conjugation or oxidation was insignificant. The endogenous concentration of BA + N6-benzyladenosine was 20-fold higher than the exogenously applied BA during the competence acquisition phase (Days 0-3). The concentration of isoprenoid-type CKs also increased 16-fold and then decreased during this time. Induction of shoot buds (Days 4-8) was characterized by a second peak of BA uptake by explants that triggered the synthesis of N6-benzyladenosine-5 -monophosphate and by the maintenance of isoprenoid-type CKs. Reestablishment of CK homeostasis marked the shift from the induction phase to the shoot development phase in this organogenic process (Days 8-12).
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Affiliation(s)
- P Moncaleán
- Instituto Vasco de Investigación y Desarrollo Agrario, Centro Arkaute, Apdo. 46, 01080 Vitoria, Pais Vasco, Spain
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Miyamoto K, Oka M, Ueda J, Hoson T, Kamisaka S. The senescence of oat leaf segments is promoted under simulated microgravity condition on a three-dimensional clinostat. Biol Sci Space 1995; 9:327-30. [PMID: 11541893 DOI: 10.2187/bss.9.327] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Plants have evolved on the earth, indicating the morphology, growth and development, and life cycle of plants are highly influenced by gravity as well as other environmental stimuli. Indeed, simulated microgravity on a clinostat or hypergravity on a centrifuge has recently been reported to change the growth and development of plants (Hoson et al. 1992, 1993, 1995, Rasmussen et al. 1994, Kasahara et al. 1995). Senescence is a final drastic phenomenon in life cycle of plants, which is characterized by the loss of total chlorophyll and protein, and/or the formation of the abscission (Osborne 1973, Thimann 1977, Addicott 1982). Many environmental stimuli as well as the qualitative and quantitative changes of plant hormones have been reported to affect plant senescence. Among those stimuli, light is the most important factor to regulate plant senescence (Leopold 1964). Dark condition promotes leaf senescence due to the decrease in endogenous level of cytokinin and/or the increase in that of abscisic acid or ethylene (Tetley and Thimann 1974, Gepstein and Thimann 1980). However, there are few reports concerning the effect of gravity on leaf senescence. Strenuous effort to learn leaf senescence under microgravity condition has been done using a three-dimensional (3-D) clinostat. In this paper, we report that simulated microgravity condition on a 3-D clinostat promoted the senescence of oat leaf segments in the dark. A possible mechanism of microgravity condition on promoting the senescence is also discussed.
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Affiliation(s)
- K Miyamoto
- College of Integrated Arts and Sciences, Osaka Prefecture University, Sakai, Japan
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Dons JJ, Valantijn M, Schilperoort RA, Van Duijn P. Nuclear DNA content and phytohormone requirements of normal, Crown gall and habituated tissues of Nicotiana tabacum var. White Burley. Exp Cell Res 1974; 89:283-94. [PMID: 4141965 DOI: 10.1016/0014-4827(74)90792-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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