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Aoki MM, Kisiala AB, Li S, Stock NL, Brunetti CR, Huber RJ, Emery RJN. Cytokinin Detection during the Dictyostelium discoideum Life Cycle: Profiles Are Dynamic and Affect Cell Growth and Spore Germination. Biomolecules 2019; 9:E702. [PMID: 31694277 PMCID: PMC6920973 DOI: 10.3390/biom9110702] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 01/18/2023] Open
Abstract
Cytokinins (CKs) are a family of evolutionarily conserved growth regulating hormones. While CKs are well-characterized in plant systems, these N6-substituted adenine derivatives are found in a variety of organisms beyond plants, including bacteria, fungi, mammals, and the social amoeba, Dictyostelium discoideum. Within Dictyostelium, CKs have only been studied in the late developmental stages of the life cycle, where they promote spore encapsulation and dormancy. In this study, we used ultra high-performance liquid chromatography-positive electrospray ionization-high resolution tandem mass spectrometry (UHPLC-(ESI+)-HRMS/MS) to profile CKs during the Dictyostelium life cycle: growth, aggregation, mound, slug, fruiting body, and germination. Comprehensive profiling revealed that Dictyostelium produces 6 CK forms (cis-Zeatin (cZ), discadenine (DA), N6-isopentenyladenine (iP), N6-isopentenyladenine-9-riboside (iPR), N6-isopentenyladenine-9-riboside-5' phosphate (iPRP), and 2-methylthio-N6-isopentenyladenine (2MeSiP)) in varying abundance across the sampled life cycle stages, thus laying the foundation for the CK biosynthesis pathway to be defined in this organism. Interestingly, iP-type CKs were the most dominant CK analytes detected during growth and aggregation. Exogenous treatment of AX3 cells with various CK types revealed that iP was the only CK to promote the proliferation of cells in culture. In support of previous studies, metabolomics data revealed that DA is one of the most significantly upregulated small molecules during Dictyostelium development, and our data indicates that total CK levels are highest during germination. While much remains to be explored in Dictyostelium, this research offers new insight into the nature of CK biosynthesis, secretion, and function during Dictyostelium growth, development, and spore germination.
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Affiliation(s)
- Megan M. Aoki
- Department of Biology, Trent University, Peterborough, ON K9L 0G2 Canada; (A.B.K.); (C.R.B.); (R.J.H.); (R.J.N.E.)
| | - Anna B. Kisiala
- Department of Biology, Trent University, Peterborough, ON K9L 0G2 Canada; (A.B.K.); (C.R.B.); (R.J.H.); (R.J.N.E.)
| | - Shaojun Li
- Noblegen, Peterborough, ON K9L 0G2, Canada;
| | - Naomi L. Stock
- Water Quality Centre, Trent University, Peterborough, ON K9L 0G2, Canada;
| | - Craig R. Brunetti
- Department of Biology, Trent University, Peterborough, ON K9L 0G2 Canada; (A.B.K.); (C.R.B.); (R.J.H.); (R.J.N.E.)
| | - Robert J. Huber
- Department of Biology, Trent University, Peterborough, ON K9L 0G2 Canada; (A.B.K.); (C.R.B.); (R.J.H.); (R.J.N.E.)
| | - R. J. Neil Emery
- Department of Biology, Trent University, Peterborough, ON K9L 0G2 Canada; (A.B.K.); (C.R.B.); (R.J.H.); (R.J.N.E.)
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Ajitkumar P, Cherayil JD. Thionucleosides in transfer ribonucleic acid: diversity, structure, biosynthesis, and function. Microbiol Rev 1988; 52:103-13. [PMID: 3280963 PMCID: PMC372707 DOI: 10.1128/mr.52.1.103-113.1988] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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3
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Wise DS, Townsend LB. Synthesis of the Selenium Analog of the Cytokinin 6-(3-Methyl-2-Butenylamino)-2-Methylthio-9-(β-D-Ribofuranosyl)Purine. ACTA ACUST UNITED AC 1986. [DOI: 10.1080/07328318608068693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ajitkumar P, Cherayil JD. Presence of 2-methylthioribosyl-trans-zeatin in Azotobacter vinelandii tRNA. J Bacteriol 1985; 162:752-5. [PMID: 3988713 PMCID: PMC218914 DOI: 10.1128/jb.162.2.752-755.1985] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Hydroxylated cytokinin, 2-methylthio-N6-(4-hydroxy-3-methylbut-2-enyl) adenosine, was found in the tRNA of Azotobacter vinelandii. This cytokinin had the trans configuration, unlike the cis configuration reported for that from other bacteria. Culture-condition-dependent changes in the content of this thiocytokinin and a few other thionucleosides in the tRNA of this bacterium have been observed.
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6
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Kim SG, Chatfield J, Armstrong DJ. Trace enrichment of cytokinins using neutral polystyrene resins. J Chromatogr A 1985. [DOI: 10.1016/s0021-9673(01)90434-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Whenham RJ. Evaluation of selective detectors for the rapid and sensitive gas chromatographic assay of cytokinins, and application to the analysis of cytokinins in plant extracts. PLANTA 1983; 157:554-560. [PMID: 24264422 DOI: 10.1007/bf00396888] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/1982] [Accepted: 01/11/1983] [Indexed: 06/02/2023]
Abstract
The performances of four gas chromatographic detectors (nitrogen-phosphorus, flamephotometric, electron-capture and flame-ionisation) were compared for the analysis of permethylated cytokinins. The nitrogen-phosphorus and flame-photometric detectors (selective for nitrogen and sulphur-containing compounds respectively) gave greatly enhanced sensitivity and-or specificity compared with the flame-ionisation detector for a wide range of cytokinin types. The response of the electron-capture and flame-ionisation detectors was quantitatively similar. The improved performance of the nitrogen-phosphorus and flame-photometric detectors was used to develop rapid and simple purification techniques for the assay of zeatin and zeatin riboside in coconut milk; dihydrozeatin and dihydrozeatin riboside in bean leaves and cytokinin nucleosides in wheat-germ transfer RNA.
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Affiliation(s)
- R J Whenham
- Biochemistry Section, National Vegetable Research Station, Wellesbourne, CV35 9EF, Warwick, UK
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8
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Kemp TR, Andersen RA, Oh J. Cytokinin determination in tRNA by fused-silica capillary gas chromatography and nitrogen-selective detection. J Chromatogr A 1983. [DOI: 10.1016/s0021-9673(01)88017-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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9
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Dirheimer G. Chemical nature, properties, location, and physiological and pathological variations of modified nucleosides in tRNAs. Recent Results Cancer Res 1983; 84:15-46. [PMID: 6342070 DOI: 10.1007/978-3-642-81947-6_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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10
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ytokinins and Changes in Their Activity During the Development of Grains of Wheat (Triticum aestivum L.). ACTA ACUST UNITED AC 1982. [DOI: 10.1016/s0044-328x(82)80051-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Does tobacco mosaic virus RNA contain cytokinins? Virology 1982; 118:263-6. [DOI: 10.1016/0042-6822(82)90343-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/1981] [Accepted: 01/05/1982] [Indexed: 11/23/2022]
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12
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Maaß H, Klämbt D. On the biogenesis of cytokinins in roots of Phaseolus vulgaris. PLANTA 1981; 151:353-358. [PMID: 24301978 DOI: 10.1007/bf00393290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/1980] [Accepted: 12/29/1980] [Indexed: 06/02/2023]
Abstract
Roots of intact bean plants were supplied with [(14)C]adenine by pulse-chase experiments. The rate of incorporation of radioactivity into tRNA and oligonucleotides of roots as well as the content of radioactive labeled cytokinin nucleotides in these RNA fractions were determined. On the average, 1/70 of the radioactivity incorporated into tRNA was localized in N(6)(Δ(2)isopentenyl)adenosine. The half life of tRNA was estimated to be 65-70 h. Shortly after the pulse period, oligonucleotides contained zeatin riboside at a ratio of 1:800, on the basis of radioactivity. The half life of these oligonucleotides was determined to be about 8 h. The main free radioactive cytokinin of roots and leaves was zeatin. Comparing the rate of degradation of (14)C-labeled tRNA and the oligonucleotides of roots and the rate of appearance of radioactive cytokinins in roots and leaves, we found strong indications for their dependency. The results contradict the hypothesis of de novo synthesis of cytokinins in roots of intact bean plants.
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Affiliation(s)
- H Maaß
- Botanisches Institut der Universität Bonn, Meckenheimer Allee 170, D-5300, Bonn, Germany
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Lenfant M, Garcia-Giralt E, Di Giusto L, Thomas M. The purification of an immunosuppressive factor extracted from bovine spleen--III. Purification process. Mol Immunol 1980; 17:119-26. [PMID: 6987487 DOI: 10.1016/0161-5890(80)90131-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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14
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Hashizume T, Sugiyama T, Imura M, Cory HT, Scott MF, McCloskey JA. Determination of cytokinins by mass spectrometry based on stable isotope dilution. Anal Biochem 1979; 92:111-22. [PMID: 371461 DOI: 10.1016/0003-2697(79)90631-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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15
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Burrows WJ. Evidence in support of biosynthesis de novo of free cytokinins. PLANTA 1978; 138:53-57. [PMID: 24413941 DOI: 10.1007/bf00392914] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/1977] [Accepted: 10/14/1977] [Indexed: 06/03/2023]
Abstract
The four cytokinins in the tRNA from Lupinus luteus L. seeds have been purified and identified as ribosyl-cis-zeatin, 2-methylthio-ribosylzeatin, (Δ (2)-isopentenyl)adenosine and 2-methylthio-N(6)-(Δ (2)-isopentenyl)adenosine. These structures have been assigned on the basis of their chromatographic mobilities and the spectroscopic data of the parent materials and their silylated derivatives. The tRNA isolated from Populus x robusta Schneid. leaves contained four cytokinins with identical chromatographic properties to those identified in Lupinus luteus seed tRNA. No evidence was obtained for the presence, in tRNA, of the naturally occurring free cytokinins identified in these plant species, dihydrozeatin (Lupinus luteus) and N(6)-(2-hydroxybenzyl)adenosine (Populus x robusta). This is evidence in support of the possibility that free cytokinins can arise by biosynthesis de novo and are not exclusively by-products released intact during tRNA turnover.
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Affiliation(s)
- W J Burrows
- Physiology and Biological Chemistry Division, Shell Biosciences Laboratory, Shell Research Ltd., ME9 8AG, Sittingbourne, U.K
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Keith G, Guerrier-Takada C, Grosjean H, Dirheimer G. A revised sequence for Bacillus stearothermophilus phenylalanine tRNA. FEBS Lett 1977; 84:241-3. [PMID: 598504 DOI: 10.1016/0014-5793(77)80697-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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17
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Cherayil JD, Lipsett MN. Zeatin ribonucleosides in the transfer ribonucleic acid of Rhizobium leguminosarum, Agrobacterium tumefaciens, Corynebacterium fascians, and Erwinia amylovora. J Bacteriol 1977; 131:741-4. [PMID: 893341 PMCID: PMC235524 DOI: 10.1128/jb.131.3.741-744.1977] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Until recently, the presence in transfer ribonucleic acid (tRNA) of the hydroxylated cytokinin ribosylzeatin [N6-(4-hydroxy-3-methylbut-2-enyl)adenosine]was thought to be unique to higher plants. This extension of work from several laboratories indicates the presence of 2-methylthioribosylzeatin in the tRNA of the plant-associated bacteria Rhizobium leguminosarum, Agrobacterium tumefaciens, and Corynebacterium fascians, but not in that of Erwinia amylovora. This cytokinin has the cis configuration, as is normally found in the tRNA's of plants. The tRNA thionucleotide patterns in these bacteria are different from those of Escherichia coli, Bacillus subtilis, and Salmonella typhimurium, which contain the unhydroxylated analogs of ribosylzeatin or 2-methylthioribosylzeatin.
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Swaminathan S, Bock RM. Isolation and identification of cytokinins from Euglena gracilis transfer ribonucleic acid. Biochemistry 1977; 16:1355-60. [PMID: 402938 DOI: 10.1021/bi00626a018] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Three ribonucleosides responsible for cytokinin activity in Euglena gracilis var Bacillaris tRNA have been isolated and identified as 6-(3-methyl-2-butenylamino)-9-beta-D-ribofuranosylpurine, 6-(4-hydroxy-3-methyl-cis-2-butenylamino)-9-beta-D-ribofuranosylpurine, and 6-(4-hydroxy-3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine. The structures of these compounds were assigned on the basis of their chromatographic properties and ultraviolet and mass spectra which were identical with those of the corresponding synthetic compounds. The elution profiles of cytokinin bioassay activity and of 35S radioactivity suggest the presence of a trace amount of 6-(3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine.
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Burrows WJ. Mode of action of N,N'-diphenylurea: The isolation and identification of the cytokinins in the transfer RNA from tobacco callus grown in the presence of N,N'-diphenylurea. PLANTA 1976; 130:313-316. [PMID: 24424645 DOI: 10.1007/bf00387838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/1976] [Accepted: 02/23/1976] [Indexed: 06/03/2023]
Abstract
The tRNA from cytokinin-dependent tobacco callus (Nicotiana tabacum) grown on mineral medium containing N,N'-diphenylurea as the source of cytokinin was found to contain 3 cytokinin-active ribonucleosides. The 2 ribonucleosides present in the largest amounts were identified conclusively by their chromatographic properties, ultra-violet and low-resolution mass spectra as the naturally-occurring cytokinins 6-(4-hydroxy-3-methyl-cis-2-butenylamino)-9-β-D-ribofuranosylpurine and 6-(3-methyl-2-butenylamino)-9-β-ribofuranosylpurine. A third ribonucleoside, present in smaller amounts, was identified as another naturally-occurring cytokinin 6-(4-hydroxy-3-methyl-2-butenylamino)-2-methylthio-9-β-D-ribofuranosylpurine on the basis of its chromatographic behaviour. No evidence was found to associate the mode of action of the non-purine cytokinin, N,N'-diphenylurea, with tRNA.
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Affiliation(s)
- W J Burrows
- Biochemistry and Physiology Division Woodstock Laboratory, Sittingbourne Research Centre, Shell Research Ltd., ME9 8AG, Sittingbourne, UK
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20
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Reda F. Endogenous cytokinins in vernalized winter wheat grains. PLANTA 1976; 130:265-268. [PMID: 24424638 DOI: 10.1007/bf00387831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/1975] [Accepted: 02/09/1976] [Indexed: 06/03/2023]
Abstract
The soybean callus assay was used to study the effect of vernalization on the endogenous cytokinin levels of the grains of winter wheat (Triticum vulgare L.), cv. Ferto and Fema. Vernalization of the grains was carried out at 3° C in the dark for 0, 9, 18, 27, 36 and 45 days. Cytokinin activities could be detected in both the aqueous and butanol extracts of vernalized grains of both cultivars. It is suggested that flowering of winter wheat may involve changes in the levels of endogenous cytokinins during vernalization.
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Affiliation(s)
- F Reda
- Botany Laboratory, National Research Centre, Dokki, Cairo, Egypt
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21
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Hecht SM, Frye RB, Werner D, Hawrelak SD, Skoog F, Schmitz RY. On the "activation" of cytokinins. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)40950-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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22
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Thimmappaya B, Cherayil JD. Unique presence of 2-methylthio-ribosylzeatin in the transfer ribonucleic acid of the bacterium Pseudomonas aeruginosa. Biochem Biophys Res Commun 1974; 60:665-72. [PMID: 4214477 DOI: 10.1016/0006-291x(74)90292-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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23
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LEONARD NELSONJ. Chemistry of the Cytokinins. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/b978-0-12-612407-1.50008-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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24
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Beutelmann P. [Studies on the biosynthesis of a cytokinin in callus cells of moss sporophytes]. PLANTA 1973; 112:181-190. [PMID: 24469899 DOI: 10.1007/bf00388588] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/1973] [Indexed: 06/03/2023]
Abstract
When callus cells derived from the sporogon of the hybrid Funaria hygrometrica x Physcomitrium piriforme are supplied with adenine-8-(14)C, they produce a labelled cytokinin which has the same chromatographic behavior as N(6)-γγ-(dimethylallyl)aminopurine. The cytokinin is the first radioactive product that can be detected in the culture medium. It is formed as long as labelled adenine is available. When callus cells are grown in an optimum culture medium containing amino acids, about 10% of the radioactivity supplied as adenine is found in the cytokinin. When the cells are grown in a medium without amino acids, the RNA-content of the cells and the total yield of cytokinin decrease, but about 18% of the radioactivity is taken up into RNA as adenine and guanine, which are both degraded to allantoin and urea but not converted to cytokinin. Free guanine is converted neither to adenine nor to cytokinin.Weak cytokinin activity can be detected in hydrolysates of sRNA, but no radioactive cytokinin can be isolated from sRNA of adenine-labelled callus cells. it is assumed that free cytokinin is not a degradation product of tRNA.
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Affiliation(s)
- P Beutelmann
- Institut für Allgemeine Botanik der Universität, D-6500, Mainz, Federal Republic of Germany
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25
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Hecht SM, McDonald JJ. Mass spectra of some 6-substituted ureidopurines and N 6 -acyladenines. Anal Biochem 1972; 47:157-73. [PMID: 5031108 DOI: 10.1016/0003-2697(72)90289-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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26
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A Speculative View of Tobacco Alkaloid Biosynthesis. ACTA ACUST UNITED AC 1972. [DOI: 10.1016/b978-0-12-612405-7.50016-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Hecht SM, Bock RM, Schmitz RY, Skoog F, Leonard NJ. Cytokinins: development of a potent antagonist. Proc Natl Acad Sci U S A 1971; 68:2608-10. [PMID: 5289891 PMCID: PMC389478 DOI: 10.1073/pnas.68.10.2608] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A systematic search has resulted in the synthesis of a class of cytokinin antimetabolites. The development and biological properties of the anticytokinins are discussed in terms of one member of the class, 3- methyl - 7 - (3 - methylbutylamino)pyrazolo[4,3 - d]- pyrimidine.
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Playtis AJ, Leonard NJ. The synthesis of ribosyl-cis-zeatin and thin layer chromatographic separation of the cis and trans isomers of ribosylzeatin. Biochem Biophys Res Commun 1971; 45:1-5. [PMID: 5139923 DOI: 10.1016/0006-291x(71)90041-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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30
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McMullan RK, Sundaralingam M. The crystal structure of N 6 -( 2 -isopentenyl)-2-methylthioadenine, a modified base of tRNA with cytokinin activity. Biochem Biophys Res Commun 1971; 43:1158-63. [PMID: 5568184 DOI: 10.1016/0006-291x(71)90584-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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31
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Alam SN, Hall RH. Separation of the delta-2 and delta-3 isomers of N6-(delta-2-isopentenyl)adenosine by gas chromatography and characterization by mass spectroscopy. Anal Biochem 1971; 40:424-8. [PMID: 5551552 DOI: 10.1016/0003-2697(71)90402-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Kwong TC, Lane BG. Differential labelling of the thio, carboxymethyl and methyl substituents of 2-thio-5-carboxymethyluridine methyl ester, a trace nucleoside constituent of yeast transfer RNA. BIOCHIMICA ET BIOPHYSICA ACTA 1970; 224:405-12. [PMID: 5498073 DOI: 10.1016/0005-2787(70)90573-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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36
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37
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