1
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Tran QH, Eder OM, Winkler A. Dynamics-driven allosteric stimulation of diguanylate cyclase activity in a red light-regulated phytochrome. J Biol Chem 2024; 300:107217. [PMID: 38522512 PMCID: PMC11035067 DOI: 10.1016/j.jbc.2024.107217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 03/26/2024] Open
Abstract
Sensor-effector proteins integrate information from different stimuli and transform this into cellular responses. Some sensory domains, like red-light responsive bacteriophytochromes, show remarkable modularity regulating a variety of effectors. One effector domain is the GGDEF diguanylate cyclase catalyzing the formation of the bacterial second messenger cyclic-dimeric-guanosine monophosphate. While critical signal integration elements have been described for different phytochromes, a generalized understanding of signal processing and communication over large distances, roughly 100 Å in phytochrome diguanylate cyclases, is missing. Here we show that dynamics-driven allostery is key to understanding signal integration on a molecular level. We generated protein variants stabilized in their far-red-absorbing Pfr state and demonstrated by analysis of conformational dynamics using hydrogen-deuterium exchange coupled to mass spectrometry that single amino acid replacements are accompanied by altered dynamics of functional elements throughout the protein. We show that the conformational dynamics correlate with the enzymatic activity of these variants, explaining also the increased activity of a non-photochromic variant. In addition, we demonstrate the functional importance of mixed Pfr/intermediate state dimers using a fast-reverting variant that still enables wild-type-like fold-changes of enzymatic stimulation by red light. This supports the functional role of single protomer activation in phytochromes, a property that might correlate with the non-canonical mixed Pfr/intermediate-state spectra observed for many phytochrome systems. We anticipate our results to stimulate research in the direction of dynamics-driven allosteric regulation of different bacteriophytochrome-based sensor-effectors. This will eventually impact design strategies for the creation of novel sensor-effector systems for enriching the optogenetic toolbox.
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Affiliation(s)
- Quang Hieu Tran
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | | | - Andreas Winkler
- Institute of Biochemistry, Graz University of Technology, Graz, Austria; BioTechMed Graz, Graz, Austria.
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2
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Shenkutie SM, Nagano S, Hughes J. Expression, purification and crystallization of the photosensory module of phytochrome B (phyB) from Sorghum bicolor. Acta Crystallogr F Struct Biol Commun 2024; 80:59-66. [PMID: 38376821 PMCID: PMC10910535 DOI: 10.1107/s2053230x24000827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 01/22/2024] [Indexed: 02/21/2024] Open
Abstract
Sorghum, a short-day tropical plant, has been adapted for temperate grain production, in particular through the selection of variants at the MATURITY loci (Ma1-Ma6) that reduce photoperiod sensitivity. Ma3 encodes phytochrome B (phyB), a red/far-red photochromic biliprotein photoreceptor. The multi-domain gene product, comprising 1178 amino acids, autocatalytically binds the phytochromobilin chromophore to form the photoactive holophytochrome (Sb.phyB). This study describes the development of an efficient heterologous overproduction system which allows the production of large quantities of various holoprotein constructs, along with purification and crystallization procedures. Crystals of the Pr (red-light-absorbing) forms of NPGP, PGP and PG (residues 1-655, 114-655 and 114-458, respectively), each C-terminally tagged with His6, were successfully produced. While NPGP crystals did not diffract, those of PGP and PG diffracted to 6 and 2.1 Å resolution, respectively. Moving the tag to the N-terminus and replacing phytochromobilin with phycocyanobilin as the ligand produced PG crystals that diffracted to 1.8 Å resolution. These results demonstrate that the diffraction quality of challenging protein crystals can be improved by removing flexible regions, shifting fusion tags and altering small-molecule ligands.
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Affiliation(s)
- Sintayehu Manaye Shenkutie
- Department of Plant Physiology, Justus Liebig University Giessen, Senckenbergstrasse 3, 35390 Giessen, Germany
- Department of Chemistry, Hawassa University, PO Box 05, Hawassa, Ethiopia
| | - Soshichiro Nagano
- Department of Plant Physiology, Justus Liebig University Giessen, Senckenbergstrasse 3, 35390 Giessen, Germany
| | - Jon Hughes
- Department of Plant Physiology, Justus Liebig University Giessen, Senckenbergstrasse 3, 35390 Giessen, Germany
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3
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Sineshchekov VA. Applications of fluorescence spectroscopy in the investigation of plant phytochrome invivo. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 208:108434. [PMID: 38412703 DOI: 10.1016/j.plaphy.2024.108434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/08/2024] [Accepted: 02/10/2024] [Indexed: 02/29/2024]
Abstract
Fluorometry is an effective research tool in biology and medicine; it is widely used in the study of the photosynthetic pigment apparatus in vivo. This method can be applied to the key plant photoreceptor phytochrome (phy). The fluorescence of phytochrome in plants was recorded for the first time in the group of the author, and a spectrofluorometric technique for its in vivo study was developed. The photophysical and photochemical properties of the pigment were described, and the photoreceptor was shown to be present in plants as two phenomenological types-active (at cryogenic temperatures) and water-soluble (Pr') and inactive and amphiphilic (Pr″). The scheme of the photoreaction explaining their photochemical distinctions was proposed. Phytochrome A was shown to comprise both types (phyA' and phyA″), whereas phytochrome B was only the second type. For phyA', distinct conformers have been detected. phyA' and phyA″ differ by the N-terminus of the molecule, possibly by serine phosphorylation. They mediate, respectively, the very low fluence and high irradiance photoresponses. Light, internal factors (kinase/phosphatase balance, pH), and hormones (jasmonate) were shown to affect the content and functions of the two phyA pools. All this points to the effectiveness of the developed method for invivo investigations of the phytochrome system. The data obtained can be applied in practical terms in agrobiology and light culture, as well as in the use of phytochrome as a new nanotool and a fluorescent probe.
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Affiliation(s)
- V A Sineshchekov
- Biology Department, M. V. Lomonosov Moscow State University, Moscow, 119234, Russia.
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4
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Wang J, Zhou C, Guan Z, Wang Q, Zhao J, Wang L, Zhang L, Zhang D, Deng XW, Ma L, Yin P. Plant phytochrome A in the Pr state assembles as an asymmetric dimer. Cell Res 2023; 33:802-805. [PMID: 37402899 PMCID: PMC10542778 DOI: 10.1038/s41422-023-00847-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 06/24/2023] [Indexed: 07/06/2023] Open
Affiliation(s)
- Jiao Wang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Chen Zhou
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Zeyuan Guan
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Qiang Wang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jun Zhao
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Weifang, Shandong, China
| | - Lixia Wang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Liuqing Zhang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Delin Zhang
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Xing Wang Deng
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Weifang, Shandong, China
| | - Ling Ma
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China.
| | - Ping Yin
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, China.
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5
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Zhang Y, Lin X, Ma C, Zhao J, Shang X, Wang Z, Xu B, Gao N, Deng XW, Wang J. Structural insights into plant phytochrome A as a highly sensitized photoreceptor. Cell Res 2023; 33:806-809. [PMID: 37491602 PMCID: PMC10542756 DOI: 10.1038/s41422-023-00858-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/16/2023] [Indexed: 07/27/2023] Open
Affiliation(s)
- Yuxuan Zhang
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Xiaoli Lin
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing, China
| | - Chengying Ma
- Peking-Tsinghua Joint Center for Life Sciences, Peking University, Beijing, China
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing, China
| | - Jun Zhao
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
| | - Xiaojin Shang
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
| | - Zhengdong Wang
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing, China
- Peking-Tsinghua Joint Center for Life Sciences, Peking University, Beijing, China
| | - Bin Xu
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China
| | - Ning Gao
- Peking-Tsinghua Joint Center for Life Sciences, Peking University, Beijing, China
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing, China
| | - Xing Wang Deng
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China.
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing, China.
- Peking-Tsinghua Joint Center for Life Sciences, Peking University, Beijing, China.
| | - Jizong Wang
- National Key Laboratory of Wheat Improvement, Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agriculture Sciences at Weifang, Weifang, Shandong, China.
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, Beijing, China.
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6
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Burgie ES, Li H, Gannam ZTK, McLoughlin KE, Vierstra RD, Li H. The structure of Arabidopsis phytochrome A reveals topological and functional diversification among the plant photoreceptor isoforms. NATURE PLANTS 2023; 9:1116-1129. [PMID: 37291396 PMCID: PMC10546791 DOI: 10.1038/s41477-023-01435-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 05/10/2023] [Indexed: 06/10/2023]
Abstract
Plants employ a divergent cohort of phytochrome (Phy) photoreceptors to govern many aspects of morphogenesis through reversible photointerconversion between inactive Pr and active Pfr conformers. The two most influential are PhyA whose retention of Pfr enables sensation of dim light, while the relative instability of Pfr for PhyB makes it better suited for detecting full sun and temperature. To better understand these contrasts, we solved, by cryo-electron microscopy, the three-dimensional structure of full-length PhyA as Pr. Like PhyB, PhyA dimerizes through head-to-head assembly of its C-terminal histidine kinase-related domains (HKRDs), while the remainder assembles as a head-to-tail light-responsive platform. Whereas the platform and HKRDs associate asymmetrically in PhyB dimers, these lopsided connections are absent in PhyA. Analysis of truncation and site-directed mutants revealed that this decoupling and altered platform assembly have functional consequences for Pfr stability of PhyA and highlights how plant Phy structural diversification has extended light and temperature perception.
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Affiliation(s)
- E Sethe Burgie
- Department of Biology, Washington University in St. Louis, St. Louis, MO, USA
| | - Hua Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - Zira T K Gannam
- Department of Biology, Washington University in St. Louis, St. Louis, MO, USA
| | - Katrice E McLoughlin
- Department of Biology, Washington University in St. Louis, St. Louis, MO, USA
- Burning Rock Dx, Irvine, CA, USA
| | - Richard D Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, MO, USA.
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.
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7
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Hildebrandt P. Vibrational Spectroscopy of Phytochromes. Biomolecules 2023; 13:1007. [PMID: 37371587 DOI: 10.3390/biom13061007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
Phytochromes are biological photoswitches that translate light into physiological functions. Spectroscopic techniques are essential tools for molecular research into these photoreceptors. This review is directed at summarizing how resonance Raman and IR spectroscopy contributed to an understanding of the structure, dynamics, and reaction mechanism of phytochromes, outlining the substantial experimental and theoretical challenges and describing the strategies to master them. It is shown that the potential of the various vibrational spectroscopic techniques can be most efficiently exploited using integral approaches via a combination of theoretical methods as well as other experimental techniques.
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Affiliation(s)
- Peter Hildebrandt
- Institut für Chemie, Technische Universität Berlin, Sekr. PC 14, Straße des 17. Juni 135, D-10623 Berlin, Germany
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8
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Sakeef N, Scandola S, Kennedy C, Lummer C, Chang J, Uhrig RG, Lin G. Machine learning classification of plant genotypes grown under different light conditions through the integration of multi-scale time-series data. Comput Struct Biotechnol J 2023; 21:3183-3195. [PMID: 37333861 PMCID: PMC10275741 DOI: 10.1016/j.csbj.2023.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 05/04/2023] [Accepted: 05/04/2023] [Indexed: 06/20/2023] Open
Abstract
In order to mitigate the effects of a changing climate, agriculture requires more effective evaluation, selection, and production of crop cultivars in order to accelerate genotype-to-phenotype connections and the selection of beneficial traits. Critically, plant growth and development are highly dependent on sunlight, with light energy providing plants with the energy required to photosynthesize as well as a means to directly intersect with the environment in order to develop. In plant analyses, machine learning and deep learning techniques have a proven ability to learn plant growth patterns, including detection of disease, plant stress, and growth using a variety of image data. To date, however, studies have not assessed machine learning and deep learning algorithms for their ability to differentiate a large cohort of genotypes grown under several growth conditions using time-series data automatically acquired across multiple scales (daily and developmentally). Here, we extensively evaluate a wide range of machine learning and deep learning algorithms for their ability to differentiate 17 well-characterized photoreceptor deficient genotypes differing in their light detection capabilities grown under several different light conditions. Using algorithm performance measurements of precision, recall, F1-Score, and accuracy, we find that Suport Vector Machine (SVM) maintains the greatest classification accuracy, while a combined ConvLSTM2D deep learning model produces the best genotype classification results across the different growth conditions. Our successful integration of time-series growth data across multiple scales, genotypes and growth conditions sets a new foundational baseline from which more complex plant science traits can be assessed for genotype-to-phenotype connections.
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Affiliation(s)
- Nazmus Sakeef
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Sabine Scandola
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Curtis Kennedy
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Christina Lummer
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Jiameng Chang
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
| | - R. Glen Uhrig
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Guohui Lin
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
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9
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Yang Y, Stensitzki T, Lang C, Hughes J, Mroginski MA, Heyne K. Ultrafast protein response in the Pfr state of Cph1 phytochrome. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES : OFFICIAL JOURNAL OF THE EUROPEAN PHOTOCHEMISTRY ASSOCIATION AND THE EUROPEAN SOCIETY FOR PHOTOBIOLOGY 2023; 22:919-930. [PMID: 36653574 DOI: 10.1007/s43630-023-00362-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 12/27/2022] [Indexed: 01/20/2023]
Abstract
Photoisomerization is a fundamental process in several classes of photoreceptors. Phytochromes sense red and far-red light in their Pr and Pfr states, respectively. Upon light absorption, these states react via individual photoreactions to the other state. Cph1 phytochrome shows a photoisomerization of its phycocyanobilin (PCB) chromophore in the Pfr state with a time constant of 0.7 ps. The dynamics of the PCB chromophore has been described, but whether or not the apoprotein exhibits an ultrafast response too, is not known. Here, we compare the photoreaction of 13C/15N labeled apoprotein with unlabeled apoprotein to unravel ultrafast apoprotein dynamics in Cph1. In the spectral range from 1750 to 1620 cm-1 we assigned several signals due to ultrafast apoprotein dynamics. A bleaching signal at 1724 cm-1 is tentatively assigned to deprotonation of a carboxylic acid, probably Asp207, and signals around 1670 cm-1 are assigned to amide I vibrations of the capping helix close to the chromophore. These signals remain after photoisomerization. The apoprotein dynamics appear upon photoexcitation or concomitant with chromophore isomerization. Thus, apoprotein dynamics occur prior to and after photoisomerization on an ultrafast time-scale. We discuss the origin of the ultrafast apoprotein response with the 'Coulomb hammer' mechanism, i.e. an impulsive change of electric field and Coulombic force around the chromophore upon excitation.
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Affiliation(s)
- Yang Yang
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | - Till Stensitzki
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | - Christina Lang
- Institut für Pflanzenphysiologie, Justus-Liebig Universität Giessen, Senckenbergstr. 3, 35390, Giessen, Germany
| | - Jon Hughes
- Institut für Pflanzenphysiologie, Justus-Liebig Universität Giessen, Senckenbergstr. 3, 35390, Giessen, Germany
| | - Maria Andrea Mroginski
- Institut Für Chemie, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Karsten Heyne
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany.
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10
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Wahlgren WY, Claesson E, Tuure I, Trillo-Muyo S, Bódizs S, Ihalainen JA, Takala H, Westenhoff S. Structural mechanism of signal transduction in a phytochrome histidine kinase. Nat Commun 2022; 13:7673. [PMID: 36509762 PMCID: PMC9744887 DOI: 10.1038/s41467-022-34893-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 11/10/2022] [Indexed: 12/14/2022] Open
Abstract
Phytochrome proteins detect red/far-red light to guide the growth, motion, development and reproduction in plants, fungi, and bacteria. Bacterial phytochromes commonly function as an entrance signal in two-component sensory systems. Despite the availability of three-dimensional structures of phytochromes and other two-component proteins, the conformational changes, which lead to activation of the protein, are not understood. We reveal cryo electron microscopy structures of the complete phytochrome from Deinoccocus radiodurans in its resting and photoactivated states at 3.6 Å and 3.5 Å resolution, respectively. Upon photoactivation, the photosensory core module hardly changes its tertiary domain arrangement, but the connector helices between the photosensory and the histidine kinase modules open up like a zipper, causing asymmetry and disorder in the effector domains. The structures provide a framework for atom-scale understanding of signaling in phytochromes, visualize allosteric communication over several nanometers, and suggest that disorder in the dimeric arrangement of the effector domains is important for phosphatase activity in a two-component system. The results have implications for the development of optogenetic applications.
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Affiliation(s)
- Weixiao Yuan Wahlgren
- grid.8761.80000 0000 9919 9582Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Elin Claesson
- grid.8761.80000 0000 9919 9582Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Iida Tuure
- grid.9681.60000 0001 1013 7965Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Jyvaskyla, Finland
| | - Sergio Trillo-Muyo
- grid.8761.80000 0000 9919 9582Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Szabolcs Bódizs
- grid.8761.80000 0000 9919 9582Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Janne A. Ihalainen
- grid.9681.60000 0001 1013 7965Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Jyvaskyla, Finland
| | - Heikki Takala
- grid.9681.60000 0001 1013 7965Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Jyvaskyla, Finland ,grid.7737.40000 0004 0410 2071Faculty of Medicine, Anatomy, University of Helsinki, Helsinki, Finland
| | - Sebastian Westenhoff
- grid.8761.80000 0000 9919 9582Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden ,grid.8993.b0000 0004 1936 9457Department of Chemistry—BMC, Biochemistry, Uppsala University, Uppsala, Sweden
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11
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Kurttila M, Etzl S, Rumfeldt J, Takala H, Galler N, Winkler A, Ihalainen JA. The structural effect between the output module and chromophore-binding domain is a two-way street via the hairpin extension. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES : OFFICIAL JOURNAL OF THE EUROPEAN PHOTOCHEMISTRY ASSOCIATION AND THE EUROPEAN SOCIETY FOR PHOTOBIOLOGY 2022; 21:1881-1894. [PMID: 35984631 PMCID: PMC9630206 DOI: 10.1007/s43630-022-00265-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 06/30/2022] [Indexed: 11/23/2022]
Abstract
Signal transduction typically starts with either ligand binding or cofactor activation, eventually affecting biological activities in the cell. In red light-sensing phytochromes, isomerization of the bilin chromophore results in regulation of the activity of diverse output modules. During this process, several structural elements and chemical events influence signal propagation. In our study, we have studied the full-length bacteriophytochrome from Deinococcus radiodurans as well as a previously generated optogenetic tool where the native histidine kinase output module has been replaced with an adenylate cyclase. We show that the composition of the output module influences the stability of the hairpin extension. The hairpin, often referred as the PHY tongue, is one of the central structural elements for signal transduction. It extends from a distinct domain establishing close contacts with the chromophore binding site. If the coupling between these interactions is disrupted, the dynamic range of the enzymatic regulation is reduced. Our study highlights the complex conformational properties of the hairpin extension as a bidirectional link between the chromophore-binding site and the output module, as well as functional properties of diverse output modules.
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Affiliation(s)
- Moona Kurttila
- Nanoscience Center, Department of Biological and Environmental Science, University of Jyväskylä, 40014, Jyväskylä, Finland
| | - Stefan Etzl
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010, Graz, Austria
| | - Jessica Rumfeldt
- Nanoscience Center, Department of Biological and Environmental Science, University of Jyväskylä, 40014, Jyväskylä, Finland
| | - Heikki Takala
- Nanoscience Center, Department of Biological and Environmental Science, University of Jyväskylä, 40014, Jyväskylä, Finland
| | - Nadine Galler
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010, Graz, Austria
| | - Andreas Winkler
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010, Graz, Austria.
| | - Janne A Ihalainen
- Nanoscience Center, Department of Biological and Environmental Science, University of Jyväskylä, 40014, Jyväskylä, Finland.
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12
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Nagano S, Sadeghi M, Balke J, Fleck M, Heckmann N, Psakis G, Alexiev U. Improved fluorescent phytochromes for in situ imaging. Sci Rep 2022; 12:5587. [PMID: 35379835 PMCID: PMC8980088 DOI: 10.1038/s41598-022-09169-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/14/2022] [Indexed: 12/18/2022] Open
Abstract
AbstractModern biology investigations on phytochromes as near-infrared fluorescent pigments pave the way for the development of new biosensors, as well as for optogenetics and in vivo imaging tools. Recently, near-infrared fluorescent proteins (NIR-FPs) engineered from biliverdin-binding bacteriophytochromes and cyanobacteriochromes, and from phycocyanobilin-binding cyanobacterial phytochromes have become promising probes for fluorescence microscopy and in vivo imaging. However, current NIR-FPs typically suffer from low fluorescence quantum yields and short fluorescence lifetimes. Here, we applied the rational approach of combining mutations known to enhance fluorescence in the cyanobacterial phytochrome Cph1 to derive a series of highly fluorescent variants with fluorescence quantum yield exceeding 15%. These variants were characterised by biochemical and spectroscopic methods, including time-resolved fluorescence spectroscopy. We show that these new NIR-FPs exhibit high fluorescence quantum yields and long fluorescence lifetimes, contributing to their bright fluorescence, and provide fluorescence lifetime imaging measurements in E.coli cells.
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13
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Li H, Burgie ES, Gannam ZTK, Li H, Vierstra RD. Plant phytochrome B is an asymmetric dimer with unique signalling potential. Nature 2022; 604:127-133. [PMID: 35355010 PMCID: PMC9930725 DOI: 10.1038/s41586-022-04529-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 02/07/2022] [Indexed: 12/24/2022]
Abstract
Many aspects of plant photoperception are mediated by the phytochrome (Phy) family of bilin-containing photoreceptors that reversibly interconvert between inactive Pr and active Pfr conformers1,2. Despite extensive biochemical studies, full understanding of plant Phy signalling has remained unclear due to the absence of relevant 3D models. Here we report a cryo-electron microscopy structure of Arabidopsis PhyB in the Pr state that reveals a topologically complex dimeric organization that is substantially distinct from its prokaryotic relatives. Instead of an anticipated parallel architecture, the C-terminal histidine-kinase-related domains (HKRDs) associate head-to-head, whereas the N-terminal photosensory regions associate head-to-tail to form a parallelogram-shaped platform with near two-fold symmetry. The platform is internally linked by the second of two internal Per/Arnt/Sim domains that binds to the photosensory module of the opposing protomer and a preceding 'modulator' loop that assembles tightly with the photosensory module of its own protomer. Both connections accelerate the thermal reversion of Pfr back to Pr, consistent with an inverse relationship between dimer assembly and Pfr stability. Lopsided contacts between the HKRDs and the platform create profound asymmetry to PhyB that might imbue distinct signalling potentials to the protomers. We propose that this unique structural dynamism creates an extensive photostate-sensitive surface for conformation-dependent interactions between plant Phy photoreceptors and their signalling partners.
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Affiliation(s)
- Hua Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - E Sethe Burgie
- Department of Biology, Washington University in St Louis, St Louis, MO, USA
| | - Zira T K Gannam
- Department of Biology, Washington University in St Louis, St Louis, MO, USA
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.
| | - Richard D Vierstra
- Department of Biology, Washington University in St Louis, St Louis, MO, USA.
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14
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Tang K, Beyer HM, Zurbriggen MD, Gärtner W. The Red Edge: Bilin-Binding Photoreceptors as Optogenetic Tools and Fluorescence Reporters. Chem Rev 2021; 121:14906-14956. [PMID: 34669383 PMCID: PMC8707292 DOI: 10.1021/acs.chemrev.1c00194] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Indexed: 12/15/2022]
Abstract
This review adds the bilin-binding phytochromes to the Chemical Reviews thematic issue "Optogenetics and Photopharmacology". The work is structured into two parts. We first outline the photochemistry of the covalently bound tetrapyrrole chromophore and summarize relevant spectroscopic, kinetic, biochemical, and physiological properties of the different families of phytochromes. Based on this knowledge, we then describe the engineering of phytochromes to further improve these chromoproteins as photoswitches and review their employment in an ever-growing number of different optogenetic applications. Most applications rely on the light-controlled complex formation between the plant photoreceptor PhyB and phytochrome-interacting factors (PIFs) or C-terminal light-regulated domains with enzymatic functions present in many bacterial and algal phytochromes. Phytochrome-based optogenetic tools are currently implemented in bacteria, yeast, plants, and animals to achieve light control of a wide range of biological activities. These cover the regulation of gene expression, protein transport into cell organelles, and the recruitment of phytochrome- or PIF-tagged proteins to membranes and other cellular compartments. This compilation illustrates the intrinsic advantages of phytochromes compared to other photoreceptor classes, e.g., their bidirectional dual-wavelength control enabling instant ON and OFF regulation. In particular, the long wavelength range of absorption and fluorescence within the "transparent window" makes phytochromes attractive for complex applications requiring deep tissue penetration or dual-wavelength control in combination with blue and UV light-sensing photoreceptors. In addition to the wide variability of applications employing natural and engineered phytochromes, we also discuss recent progress in the development of bilin-based fluorescent proteins.
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Affiliation(s)
- Kun Tang
- Institute
of Synthetic Biology, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Hannes M. Beyer
- Institute
of Synthetic Biology, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Matias D. Zurbriggen
- Institute
of Synthetic Biology and CEPLAS, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse
1, D-40225 Düsseldorf, Germany
| | - Wolfgang Gärtner
- Retired: Max Planck Institute
for Chemical Energy Conversion. At present: Institute for Analytical Chemistry, University
Leipzig, Linnéstrasse
3, 04103 Leipzig, Germany
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15
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Probing the structural basis of Citrus phytochrome B using computational modelling and molecular dynamics simulation approaches. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116895] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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16
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Merga G, Lopez MF, Fischer P, Piwowarski P, Nogacz Ż, Kraskov A, Buhrke D, Escobar FV, Michael N, Siebert F, Scheerer P, Bartl F, Hildebrandt P. Light- and temperature-dependent dynamics of chromophore and protein structural changes in bathy phytochrome Agp2. Phys Chem Chem Phys 2021; 23:18197-18205. [PMID: 34612283 DOI: 10.1039/d1cp02494a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bacterial phytochromes are sensoric photoreceptors that transform light absorbed by the photosensor core module (PCM) to protein structural changes that eventually lead to the activation of the enzymatic output module. The underlying photoinduced reaction cascade in the PCM starts with the isomerization of the tetrapyrrole chromophore, followed by conformational relaxations, proton transfer steps, and a secondary structure transition of a peptide segment (tongue) that is essential for communicating the signal to the output module. In this work, we employed various static and time-resolved IR and resonance Raman spectroscopic techniques to study the structural and reaction dynamics of the Meta-F intermediate of both the PCM and the full-length (PCM and output module) variant of the bathy phytochrome Agp2 from Agrobacterium fabrum. In both cases, this intermediate represents a branching point of the phototransformation, since it opens an unproductive reaction channel back to the initial state and a productive pathway to the final active state, including the functional protein structural changes. It is shown that the functional quantum yield, i.e. the events of tongue refolding per absorbed photons, is lower by a factor of ca. two than the quantum yield of the primary photochemical process. However, the kinetic data derived from the spectroscopic experiments imply an increased formation of the final active state upon increasing photon flux or elevated temperature under photostationary conditions. Accordingly, the branching mechanism does not only account for the phytochrome's function as a light intensity sensor but may also modulate its temperature sensitivity.
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Affiliation(s)
- Galaan Merga
- Humboldt Universität zu Berlin, Institut für Biologie, Biophysikalische Chemie, Invalidenstr. 42, D-10115 Berlin, Germany
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17
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Burgie ES, Gannam ZTK, McLoughlin KE, Sherman CD, Holehouse AS, Stankey RJ, Vierstra RD. Differing biophysical properties underpin the unique signaling potentials within the plant phytochrome photoreceptor families. Proc Natl Acad Sci U S A 2021; 118:e2105649118. [PMID: 34039713 PMCID: PMC8179155 DOI: 10.1073/pnas.2105649118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Many aspects of photoperception by plants and microorganisms are initiated by the phytochrome (Phy) family of photoreceptors that detect light through interconversion between red light- (Pr) and far-red light-absorbing (Pfr) states. Plants synthesize a small family of Phy isoforms (PhyA to PhyE) that collectively regulate photomorphogenesis and temperature perception through redundant and unique actions. While the selective roles of these isoforms have been partially attributed to their differing abundances, expression patterns, affinities for downstream partners, and turnover rates, we show here from analysis of recombinant Arabidopsis chromoproteins that the Phy isoforms also display distinct biophysical properties. Included are a hypsochromic shift in the Pr absorption for PhyC and varying rates of Pfr to Pr thermal reversion, part of which can be attributed to the core photosensory module in each. Most strikingly, PhyB combines strong temperature dependence of thermal reversion with an order-of-magnitude faster rate to likely serve as the main physiological thermosensor, whereby thermal reversion competes with photoconversion. In addition, comparisons of Pfr occupancies for PhyA and PhyB under a range of red- and white-light fluence rates imply that low-light environments are effectively sensed by PhyA, while high-light environments, such as full sun, are effectively sensed by PhyB. Parallel analyses of the Phy isoforms from potato and maize showed that the unique features within the Arabidopsis family are conserved, thus indicating that the distinct biophysical properties among plant Phy isoforms emerged early in Phy evolution, likely to enable full interrogation of their light and temperature environments.
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Affiliation(s)
- E Sethe Burgie
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130
- Department of Genetics, University of Wisconsin, Madison, WI 53706
| | - Zira T K Gannam
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130
| | | | | | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine in St. Louis, St. Louis, MO 63110
- Center for Science and Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63110
| | - Robert J Stankey
- Department of Genetics, University of Wisconsin, Madison, WI 53706
| | - Richard D Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130;
- Department of Genetics, University of Wisconsin, Madison, WI 53706
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18
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Takala H, Edlund P, Ihalainen JA, Westenhoff S. Tips and turns of bacteriophytochrome photoactivation. Photochem Photobiol Sci 2021; 19:1488-1510. [PMID: 33107538 DOI: 10.1039/d0pp00117a] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Phytochromes are ubiquitous photosensor proteins, which control the growth, reproduction and movement in plants, fungi and bacteria. Phytochromes switch between two photophysical states depending on the light conditions. In analogy to molecular machines, light absorption induces a series of structural changes that are transduced from the bilin chromophore, through the protein, and to the output domains. Recent progress towards understanding this structural mechanism of signal transduction has been manifold. We describe this progress with a focus on bacteriophytochromes. We describe the mechanism along three structural tiers, which are the chromophore-binding pocket, the photosensory module, and the output domains. We discuss possible interconnections between the tiers and conclude by presenting future directions and open questions. We hope that this review may serve as a compendium to guide future structural and spectroscopic studies designed to understand structural signaling in phytochromes.
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Affiliation(s)
- Heikki Takala
- Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Box 35, 40014 Jyvaskyla, Finland. and Department of Anatomy, Faculty of Medicine, University of Helsinki, Box 63, 00014 Helsinki, Finland
| | - Petra Edlund
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden.
| | - Janne A Ihalainen
- Department of Biological and Environmental Science, Nanoscience Center, University of Jyvaskyla, Box 35, 40014 Jyvaskyla, Finland.
| | - Sebastian Westenhoff
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden.
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19
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Wahlgren WY, Golonka D, Westenhoff S, Möglich A. Cryo-Electron Microscopy of Arabidopsis thaliana Phytochrome A in Its Pr State Reveals Head-to-Head Homodimeric Architecture. FRONTIERS IN PLANT SCIENCE 2021; 12:663751. [PMID: 34108981 PMCID: PMC8182759 DOI: 10.3389/fpls.2021.663751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Phytochrome photoreceptors regulate vital adaptations of plant development, growth, and physiology depending on the ratio of red and far-red light. The light-triggered Z/E isomerization of a covalently bound bilin chromophore underlies phytochrome photoconversion between the red-absorbing Pr and far-red-absorbing Pfr states. Compared to bacterial phytochromes, the molecular mechanisms of signal propagation to the C-terminal module and its regulation are little understood in plant phytochromes, not least owing to a dearth of structural information. To address this deficit, we studied the Arabidopsis thaliana phytochrome A (AtphyA) at full length by cryo-electron microscopy (cryo-EM). Following heterologous expression in Escherichia coli, we optimized the solvent conditions to overcome protein aggregation and thus obtained photochemically active, near-homogenous AtphyA. We prepared grids for cryo-EM analysis of AtphyA in its Pr state and conducted single-particle analysis. The resulting two-dimensional class averages and the three-dimensional electron density map at 17 Å showed a homodimeric head-to-head assembly of AtphyA. Docking of domain structures into the electron density revealed a separation of the AtphyA homodimer at the junction of its photosensor and effector modules, as reflected in a large void in the middle of map. The overall architecture of AtphyA resembled that of bacterial phytochromes, thus hinting at commonalities in signal transduction and mechanism between these receptors. Our work paves the way toward future studies of the structure, light response, and interactions of full-length phytochromes by cryo-EM.
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Affiliation(s)
- Weixiao Yuan Wahlgren
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - David Golonka
- Lehrstuhl fur Biochemie, Universität Bayreuth, Bayreuth, Germany
| | - Sebastian Westenhoff
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Andreas Möglich
- Lehrstuhl fur Biochemie, Universität Bayreuth, Bayreuth, Germany
- Bayreuth Center for Biochemistry and Molecular Biology, Universität Bayreuth, Bayreuth, Germany
- North-Bavarian NMR Center, Universität Bayreuth, Bayreuth, Germany
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20
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Kim Y, Xu QZ, Zhao KH, Gärtner W, Matysik J, Song C. Lyophilization Reveals a Multitude of Structural Conformations in the Chromophore of a Cph2-like Phytochrome. J Phys Chem B 2020; 124:7115-7127. [PMID: 32693592 DOI: 10.1021/acs.jpcb.0c03431] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cyanobacteria sense and respond to various colors of light employing a large number of bilin-based phytochrome-like photoreceptors. All2699 from Nostoc 7120 has three consecutive GAF domains with GAF1 and GAF3 binding a phycocyanobilin chromophore. GAF1, even when expressed independently, can be photoconverted between red-absorbing Pr and far-red-absorbing Pfr states, while the nonphotosensory GAF2 domain is structurally and functionally homologous to the PHY domains in canonical and Cph2-like phytochromes. Here, we characterize possible bilin chromophore conformers using solid-state NMR spectroscopy on the two lyophilized All2699 samples (GAF1-only and GAF1-PHY constructs). On the basis of complete 1H, 13C, and 15N assignments for the chromophore obtained on the two Pr lyophilizates, multiple static conformations of the chromophore in both cases are identified. Moreover, most atoms of the chromophore in the bidomain sample show only subtle changes in the mean chemical shifts relative to those in frozen solution (FS), indicating an optimized interaction of the GAF2 domain with the GAF1-bound chromophore. Our results confirm the conservation of key chromophore-protein interactions and the photoreversibility in both All2699 lyophilizates, offering the possibility to investigate conformational distributions of the heterogeneous chromophore and its functional consequences in phytochromes and other bilin-dependent photoreceptors intractable by the solid-state NMR technique as FSs.
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Affiliation(s)
- Yunmi Kim
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany
| | - Qian-Zhao Xu
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Kai-Hong Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Wolfgang Gärtner
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany
| | - Jörg Matysik
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany
| | - Chen Song
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany
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