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Klose C, Nagy F, Schäfer E. Thermal Reversion of Plant Phytochromes. MOLECULAR PLANT 2020; 13:386-397. [PMID: 31812690 DOI: 10.1016/j.molp.2019.12.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/21/2019] [Accepted: 12/03/2019] [Indexed: 05/18/2023]
Abstract
Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development. Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion, also termed dark reversion. Although the term "dark reversion" is justified by historical reasons and frequently used in the literature, "thermal reversion" more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the review. Thermal reversion is a critical parameter for the light sensitivity of phytochrome-mediated responses and has been studied for decades, often resulting in contradictory findings. Thermal reversion is an intrinsic property of the phytochrome molecules but can be modulated by intra- and intermolecular interactions, as well as biochemical modifications, such as phosphorylation. In this review, we outline the research history of phytochrome thermal reversion, highlighting important predictions that have been made before knowing the molecular basis. We further summarize and discuss recent findings about the molecular mechanisms regulating phytochrome thermal reversion and its functional roles in light and temperature sensing in plants.
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Affiliation(s)
- Cornelia Klose
- Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany.
| | - Ferenc Nagy
- Institute of Plant Biology, Biological Research Centre, Temesvári krt. 62, 6726 Szeged, Hungary
| | - Eberhard Schäfer
- Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany
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Riemann M, Bouyer D, Hisada A, Müller A, Yatou O, Weiler EW, Takano M, Furuya M, Nick P. Phytochrome A requires jasmonate for photodestruction. PLANTA 2009; 229:1035-45. [PMID: 19184094 DOI: 10.1007/s00425-009-0891-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 01/07/2009] [Indexed: 05/23/2023]
Abstract
The plant photoreceptor phytochrome is organised in a small gene family with phytochrome A (phyA) being unique, because it is specifically degraded upon activation by light. This so called photodestruction is thought to be important for dynamic aspects of sensing such as measuring day length or shading by competitors. Signal-triggered proteolytic degradation has emerged as central element of signal crosstalk in plants during recent years, but many of the molecular players are still unknown. We therefore analyzed a jasmonate (JA)-deficient rice mutant, hebiba, that in several aspects resembles a mutant affected in photomorphogenesis. In this mutant, the photodestruction of phyA is delayed as shown by in vivo spectroscopy and Western blot analysis. Application of methyl-JA (MeJA) can rescue the delayed phyA photodestruction in the mutant in a time- and dose-dependent manner. Light regulation of phyA transcripts thought to be under control of stable phytochrome B (phyB) is still functional. The delayed photodestruction is accompanied by an elevated sensitivity of phytochrome-dependent growth responses to red and far-red light.
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Affiliation(s)
- Michael Riemann
- Institute of Botany 1, Universität Karlsruhe, Kaiserstrasse 2, 76128 Karlsruhe, Germany.
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Eichenberg K, Kunkel T, Kretsch T, Speth V, Schäfer E. In vivo characterization of chimeric phytochromes in yeast. J Biol Chem 1999; 274:354-9. [PMID: 9867850 DOI: 10.1074/jbc.274.1.354] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phytochromes are plant photoreceptors that play a major role in photomorphogenesis. Two members of the phytochrome family have been characterized in some detail. Phytochrome A, which controls very low fluence and high irradiance responses, is rapidly degraded in the light, forms sequestered areas of phytochrome (SAPs), and does not exhibit dark reversion in monocotyledonous seedlings. Phytochrome B mediates red/far-red reversible responses, is stable in the light, and does not form SAPs. We report on the behavior in yeast of the phytochrome apoproteins of rice PHYA, tobacco PHYB, and chimeric PHYAB and PHYBA and on the behavior of the respective holoprotein adducts after assembly with phycocyanobilin chromophore (PHY*). SAP-like formation in yeast was not observed for PHYB, but was detectable for PHYA, PHYAB, and PHYBA. Rice PHYA* did not undergo dark reversion in yeast. Surprisingly, all other tested phytochrome constructs did exhibit dark reversion, including chimeric phytochromes with a short N-terminal part of tobacco PHYB or parsley PHYA fused to rice PHYA. Furthermore, the proportion of phytochrome undergoing dark reversion and the rate of reversion were increased for both the N terminus-swapped constructs and PHYBA*. These results are discussed with respect to structure/function analysis of phytochromes A and B.
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Affiliation(s)
- K Eichenberg
- Institut für Biologie II, Albert-Ludwigs-Universität Freiburg, Sch anzlestrasse 1, D-79104 Freiburg, Germany
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Iino M, Shitanishi K, Wada M. Phytochrome-mediated Phototropism in Adiantum Protonemata II. Participation of Phytochrome Dark Reversion. Photochem Photobiol 1997. [DOI: 10.1111/j.1751-1097.1997.tb07965.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kunkel T, Speth V, Büche C, Schäfer E. In vivo characterization of phytochrome-phycocyanobilin adducts in yeast. J Biol Chem 1995; 270:20193-200. [PMID: 7650038 DOI: 10.1074/jbc.270.34.20193] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The in vivo reconstitution of phycocyanobilin with apophytochrome leads to photoreversible adducts in living yeast cells. Investigations with the rice phytochrome A phycocyanobilin adduct (PHYA*) and the tobacco phytochrome B phycocyanobilin adduct (PHYB*) show that the protein stability in yeast is independent of the form of the photoreceptor. After in vivo assembly and irradiation with red light, 25.6% of the far-red light-absorbing form of PHYB* exhibited dark reversion with a half-life time of approximately 20 min. Control experiments with PHYA* revealed no dark reversion. The data indicate that the molecular basis for this reaction is the formation of heterodimers between the red and the far-red light absorbing form of phytochrome. Electron microscopic in situ localizations and in vitro sequestering experiments showed that phytochrome A was able to sequester in yeast. On the electron microscopic level, the sequestered areas of phytochrome from etiolated plants and yeast are indistinguishable. The sequestering reaction in yeast is independent of the formation of the far-red light absorbing form of phytochrome. Therefore, we discuss a new model for this reaction in plants. Since it is unlikely that yeast cells contain elements that distinguish between phytochrome A and B, we conclude that sequestering and dark reversion reflect intrinsic properties of phytochrome.
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Affiliation(s)
- T Kunkel
- Institut für Biologie II, Albert-Ludwigs-Universität Freiburg, Federal Republic of Germany
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Parks BM, Shanklin J, Koornneef M, Kendrick RE, Quail PH. Immunochemically detectable phytochrome is present at normal levels but is photochemically nonfunctional in the hy 1 and hy 2 long hypocotyl mutants of Arabidopsis. PLANT MOLECULAR BIOLOGY 1989; 12:425-437. [PMID: 24272903 DOI: 10.1007/bf00017582] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/1989] [Accepted: 01/09/1989] [Indexed: 06/02/2023]
Abstract
The hy 1 and hy 2 long hypocotyl mutants of Arabidopsis thaliana contain less than 20% (the detection limit) of the phytochrome in wild-type tissue as measured by in vivo difference spectroscopy. In contrast, spectral measurements for the hy 3, hy 4, and hy 5 long hypocotyl mutants indicate that they each contain levels of phytochrome equivalent to the wild-type parent. Immunoblot analysis using a monoclonal antibody directed against the chromophore-bearing region of etiolated-oat phytochrome demonstrates that extracts of all mutant and wild-type Arabidopsis tissues, prepared by extraction of proteins into hot SDS-containing buffer, have identical levels of one major immunodetectable protein (116 kDa). An assay involving controlled in vitro proteolysis, known to produce distinctive fragmentation patterns for Pr and Pfr (Vierstra RD, Quail PH, Planta 156: 158-165, 1982), indicates that the 116 kDa polypeptide from the wild-type parent represents Arabidopsis phytochrome. The 116 kDa protein from either hy 3, hy 4, or hy 5 displays the same fragmentation pattern found for the wild type. Together with the spectral data, these results indicate that the mutant phenotype of these variants does not involve lesions in the polypeptide sequence that lead to gross conformational aberrations, and suggest that the genetic lesions may affect steps in the transduction chain downstream of the photoreceptor. In contrast, this same analysis for hy 1 and hy 2 has revealed that the 116 kDa protein from either of these mutants is not degraded differently in response to the different wavelengths of irradiation given in vitro. Moreover, whereas immunoblot analysis of tissue extracts from light-grown wild-type seedlings show that the 116 kDa phytochrome protein level is greatly reduced relative to dark-grown tissue as expected, similar extracts of light-grown hy 1 and hy 2 seedlings contain the 116 kDa polypeptide in amounts equivalent to those of dark-grown tissue. Combined, these data indicate that the hy 1 and hy 2 mutants both produce normal levels of immunochemically detectable phytochrome that is photochemically nonfunctional.
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Affiliation(s)
- B M Parks
- Plant Gene Expression Center, University of California-Berkeley/United States Department of Agriculture, 800 Buchanan St., 94710, Albany, CA, USA
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SCHAUFER E, EBERT C, SCHWEITZER M. CONTROL OF HYPOCOTYL GROWTH IN MUSTARD SEEDLINGS AFTER LIGHT-DARK TRANSITIONS. Photochem Photobiol 1984. [DOI: 10.1111/j.1751-1097.1984.tb03410.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Otto V, Mousinger E, Sauter M, Schäfer E. PHYTOCHROME CONTROL OF ITS OWN SYNTHESIS IN Sorghum vulgare AND Avena sativa. Photochem Photobiol 1983. [DOI: 10.1111/j.1751-1097.1983.tb03602.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Jabben M, Beggs C, Schaufer E. DEPENDENCE OF Pfr/Ptot-RATIOS ON LIGHT QUALITY and LIGHT QUANTITY. Photochem Photobiol 1982. [DOI: 10.1111/j.1751-1097.1982.tb02634.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Heim B, Schäfer E. Light-controlled inhibition of hypocotyl growth inSinapis alba L. seedlings : Fluence rate dependence of hourly light pulses and continuous irradiation. PLANTA 1982; 154:150-155. [PMID: 24275976 DOI: 10.1007/bf00387909] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/1981] [Accepted: 11/09/1981] [Indexed: 06/02/2023]
Abstract
Fluence rate-response curves were determined for the inhibition of hypocotyl growth in 54 h old dark-grownSinapis alba L. seedlings by continuous or hourly 5 min red light irradiation (24 h). In both cases a fluence rate-dependence was observed. More than 90% of the continuous light effect could be substituted for by hourly light pulses if the total fluence of the two different light regimes was the same. Measurements of the far red absorbing form of phytochrome ([P fr]) and [P fr]/[P tot] (total phytochrome) showed a strong fluence rate-dependence under continuous and pulsed light which partially paralleled the fluence rate-response curves for the inhibition of the hypocotyl growth.
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Affiliation(s)
- B Heim
- Biologisches Institut II der Universität, Schänzlestrasse I, D-7800, Freiburg, Germany
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Hong YN, Schopfer P. Control by phytochrome of urate oxidase and allantoinase activities during peroxisome development in the cotyledons of mustard (Sinapis alba L.) seedlings. PLANTA 1981; 152:325-335. [PMID: 24301027 DOI: 10.1007/bf00388257] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/1980] [Accepted: 02/23/1981] [Indexed: 06/02/2023]
Abstract
The peroxisomal enzyme, urate oxidase (EC 1.7.3.3), and the next enzyme of the urate pathway, allantoinase (EC 3.5.2.5), demonstrate a lightmediated rise of activity in the cotyledons of mustard (Sinapis alba L.). The capacity of the peroxisomes for urate breakdown, marked by the time course of urate oxidase, develops distinctly later than the two other peroxisome functions (fatty acid breakdown, "glyoxysomal" function; glycolate breakdown, "leaf peroxisomal" function). The light effect on urate oxidase and allantoinase is mediated through the phytochrome system in all three seedling organs (cotyledons, hypocotyl, radicle), as revealed by induction/reversion experiments with red/far-red light pulses and continuous irradiation with far-red light (high irradiance reaction of phytochrome). Both enzyme activities can be induced by phytochrome in the seedling cotyledons only during a sensitive period of about 48 h prior to the actual light-mediated rise of activity, making it necessary to assume the existence of a long-lived intermediate ("transmitter") in the signal response chain connecting enzyme formation to the phytochrome system. Detailed kinetic investigation, designed to test whether urate oxidase and allantoinase are controlled by phytochrome via the same signal response chain (coordinate induction), revealed large differences between the two enzymes: (i) a different onset of the loss of reversibility of a red light induction by a far-red light pulse (=onset of transmitter formation=coupling point; 48 h/24 h after sowing for urate oxidase/allantoinase); (ii) a different onset of the response (=onset of competence for transmitter= starting point; 72 h/48 h); (iii) full loss of reversibility (=completion of transmitter formation) is reached at different times (independence point, 90 h/52 h). These differences show that phytochrome controls urate oxidase and allantoinase via separate signal response chains. While urate oxidase can be localized in the peroxisomal fraction isolated from crude organelle extracts of the cotyledons by density gradient centrifugation, most of the allantoinase activity found in the peroxisomal fraction did not appear to be an integral part of the peroxisome but originated presumably from adhering membrane fragments.
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Affiliation(s)
- Y N Hong
- Biologisches Institut II der Universität Freiburg, Schänzlestr 1, D-7800, Freiburg, Federal Republic of Germany
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Schäfer E. VARIATION IN THE RATES OF SYNTHESIS AND DEGRADATION OF PHYTOCHROME IN COTYLEDONS OF CUCURBITA PEPO L. DURING SEEDLING DEVELOPMENT. Photochem Photobiol 1978. [DOI: 10.1111/j.1751-1097.1978.tb07676.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Johnson CB, Hilton J. Effects of light on phytochrome in cauliflower curd. PLANTA 1978; 144:13-17. [PMID: 24408639 DOI: 10.1007/bf00385002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/1978] [Accepted: 06/19/1978] [Indexed: 06/03/2023]
Abstract
The effect of light on the phytochrome content of cauliflower (Brassica oleracea (L.) var. botrytis) curd was studied using in vivo spectrophotometry. It was found that light caused a rapid increase in phytochrome level whereas transfer to darkness caused a rapid loss, regardless of the amount of phytochrome initially present in the far red absorbing form. The amount of phytochrome detectable during continuous irradiation appears to be related to the photoequilibrium φ, and is thus controlled by phytochrome itself.
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Affiliation(s)
- C B Johnson
- Department of Physiology and Environmental Studies, University of Nottingham, School of Agriculture, Sutton Bonington, LE12 5RD, Loughborough, U.K
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Oelze-Karow H, Mohr H. An attempt to localize the threshold reaction in phytochrome-mediated control of lipoxygenase synthesis in the mustard seedling. Photochem Photobiol 1976; 23:61-7. [PMID: 817339 DOI: 10.1111/j.1751-1097.1976.tb06772.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Schäfer E, Lassig TU, Schopfer P. Photocontrol of phytochrome destruction in grass seedlings. The influence of wavelength and irradiance. Photochem Photobiol 1975; 22:193-202. [PMID: 1215429 DOI: 10.1111/j.1751-1097.1975.tb06736.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Schäfer E, Schmidt W. Temperature dependence of phytochrome dark reactions. PLANTA 1974; 116:257-266. [PMID: 24458194 DOI: 10.1007/bf00390231] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/1973] [Indexed: 06/03/2023]
Abstract
The dark reversion and the destruction reaction of the phytochrome of squash (Cucurbita pepo L.) cotyledons show different temperature behaviour in the temperature range 15-35°. The Arrhenius activation energy of the destruction reaction is temperature independent whereas that of the reversion reaction shows a jump at 20°. This indicates an interaction of phytochrome molecules with membranes. A reaction scheme is discussed which can explain the differences of the dark kinetics in a quantitative manner.
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Affiliation(s)
- E Schäfer
- Institute für Biologie II und III der Universität Freiburg, Schänzlestraße 9-11, D-7800, Freiburg i.Br., Federal Republic of Germany
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Schmidt W, Schäfer E. Dependence of phytochrome dark reactions on the initial photostationary state. PLANTA 1974; 116:267-272. [PMID: 24458195 DOI: 10.1007/bf00390232] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/1973] [Indexed: 06/03/2023]
Abstract
Under conditions of continuous irradiation, the P jr destruction rate constants (k d ) of phytochrome in hooks and cotyledons of squash (Cucurbita pepo L.) seedlings do not depend on the photostationary state ϕλ and are the same in both organs. On the other hand, the rate constants of the dark reversion and the first destruction step, plotted as a function of ϕ λ (0) , show optimum curves with maxima between ϕ λ (0) and 0.5. Similar results were obtained for dark reactions of mustard (Sinapis alba L.)-hook phytochrome in vivo. This indicates a cooperative behaviour of these phytochrome dark reactions.
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Affiliation(s)
- W Schmidt
- Institute für Biologie III und II der Universität Freiburg, Schänzlestraße 9-11, D-7800, Freiburg i. Br., Federal Republic of Germany
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Drumm H, Mohr H. THE DOSE RESPONSE CURVE IN PHYTOCHROME-MEDIATED ANTHOCYANIN SYNTHESIS IN THE MUSTARD SEEDLING. Photochem Photobiol 1974. [DOI: 10.1111/j.1751-1097.1974.tb06561.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Irradiance dependency of the phytochrome system in cotyledons of mustard (Sinapis alba L.). J Math Biol 1974. [DOI: 10.1007/bf02339485] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Seitz K. Irradiance dependent far-red effects upon red induced germination of lettuce seeds. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/s0044-328x(74)80184-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Oelze-Karow H, Mohr H. QUANTITATIVE CORRELATION BETWEEN SPECTROPHOTOMETRIC PHYTOCHROME ASSAY AND PHYSIOLOGICAL RESPONSE. Photochem Photobiol 1973. [DOI: 10.1111/j.1751-1097.1973.tb06427.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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SCHÄFER E, MARCHAL B, MARMÉ D. IN VIVO MEASUREMENTS OF THE PHYTOCHROME PHOTOSTATIONARY STATE IN FAR RED LIGHT. Photochem Photobiol 1972. [DOI: 10.1111/j.1751-1097.1972.tb06257.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Schäfer E, Marchal B, Marmé D. On the phytochrome phototransformation kinetics in mustard seedlings. PLANTA 1971; 101:265-276. [PMID: 24488431 DOI: 10.1007/bf00386833] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/1971] [Indexed: 06/03/2023]
Abstract
The in vivo phototransformation kinetics of mustard hook and cotyledon phytochrome exhibit a deviation from a single first order curve, quite similar to that for pumpkin hooks as reported in a previous paper (Boisard, Marmé and Schäfer, 1971). The P fr→Prkinetics can be characterized by the ratios ɛ fr,λ (I) · P fr (I) /ɛ fr,λ (II) · P fr,λ (II) and [Formula: see text] where P fr (I) and P fr (II) are two populations of phytochrome molecules which convert to P rwith a first order half-life of [Formula: see text] and [Formula: see text]. These ratios depend on the length of time of etiolation. The ratio ɛ fr,λ (I) · P fr (I) /ɛ fr,λ (II) · P fr,λ (II) is independent of the amount of total P frpresent at the beginning of the P fr→Prphototransformation after a non-saturating dose of red light. The half-lives of the two populations, however, depend on the concentration of total P frinitially present. P fr→Prphototransformation kinetics with different light intensities show that reciprocity holds.
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Affiliation(s)
- E Schäfer
- Institute für Biologie II, III der Universität, Freiburg i. Br., Germany
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