1
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Tokutomi S, Tsunoda SP. A variety of photoreceptors and the frontiers of optogenetics. Biophys Physicobiol 2022; 19:1-3. [PMID: 35532380 PMCID: PMC8926307 DOI: 10.2142/biophysico.bppb-v19.0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/04/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
| | - Satoshi P. Tsunoda
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology
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2
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Lkhamkhuu E, Zikihara K, Katsura H, Tokutomi S, Hosokawa T, Usami Y, Ichihashi M, Yamaguchi J, Monde K. Effect of circularly polarized light on germination, hypocotyl elongation and biomass production of arabidopsis and lettuce: Involvement of phytochrome B. Plant Biotechnol (Tokyo) 2020; 37:57-67. [PMID: 32362749 PMCID: PMC7193831 DOI: 10.5511/plantbiotechnology.19.1219a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 12/19/2019] [Indexed: 06/11/2023]
Abstract
Circular dichroism (CD), defined as the differential absorption of left- and right-handed circularly polarized light (CPL), is a useful spectroscopic technique for structural studies of biological systems composed of chiral molecules. The present study evaluated the effects of CPL on germination, hypocotyl elongation and biomass production of Arabidopsis and lettuce. Higher germination rates were observed when Arabidopsis and lettuce seedlings were irradiated with red right-handed CPL (R-CPL) than with red left-handed CPL (L-CPL). Hypocotyl elongation was effectively inhibited when Arabidopsis and lettuce seedlings were irradiated with red R-CPL than with red L-CPL. This difference was not observed when a phytochrome B (phyB) deficient mutant of Arabidopsis was irradiated, suggesting that inhibition of elongation by red R-CPL was mediated by phyB. White R-CPL induced greater biomass production by adult Arabidopsis plants, as determined by their fresh shoot weight, than white L-CPL. To determine the molecular basis of these CPL effects, CD spectra and the effect of CPL on the photoreaction of a sensory module of Arabidopsis phyB were measured. The red light-absorbing form of phyB showed a negative CD in the red light-absorbing region, consistent with the results of germination, inhibition of hypocotyl elongation and biomass production. L-CPL and R-CPL, however, did not differ in their ability to induce the interconversion of the red light-absorbing and far-red light-absorbing forms of phyB. These findings suggest that these CPL effects involve phyB, along with other photoreceptors and the photosynthetic process.
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Affiliation(s)
- Enkhsukh Lkhamkhuu
- Graduate School of Life Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan
| | - Kazunori Zikihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531
| | - Hitomi Katsura
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531
- Botanical Gardens, Tohoku University, Sendai, Miyagi 980-0862, Japan
| | - Takafumi Hosokawa
- Research and Development Management Headquarters, Fuji Film Corporation, Kanagawa 258-8577, Japan
| | - Yoshihisa Usami
- Research and Development Management Headquarters, Fuji Film Corporation, Kanagawa 258-8577, Japan
| | - Mitsuyoshi Ichihashi
- Research and Development Management Headquarters, Fuji Film Corporation, Kanagawa 258-8577, Japan
| | - Junji Yamaguchi
- Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Kenji Monde
- Graduate School of Life Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan
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3
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Nakasone Y, Ohshima M, Okajima K, Tokutomi S, Terazima M. Photoreaction Dynamics of Full-Length Phototropin from Chlamydomonas reinhardtii. J Phys Chem B 2019; 123:10939-10950. [PMID: 31790257 DOI: 10.1021/acs.jpcb.9b09685] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Phototropin (phot) is a blue light sensor involved in the light responses of several species from green algae to higher plants. Phot consists of two photoreceptive domains (LOV1 and LOV2) and a Ser/Thr kinase domain. These domains are connected by a hinge and a linker domain. So far, studies on the photochemical reaction dynamics of phot have been limited to short fragments, and the reactions of intact phot have not been well elucidated. Here, the photoreactions of full-length phot and of several mutants from Chlamydomonas reinhardtii (Cr) were investigated by the transient grating and circular dichroism (CD) methods. Full-length Cr phot is in monomeric form in both dark and light states and shows conformational changes upon photoexcitation. When LOV1 is excited, the hinge helix unfolds with a time constant of 77 ms. Upon excitation of LOV2, the linker helix unfolds initially followed by a tertiary structural change of the kinase domain with a time constant of 91 ms. The quantum yield of conformational change after adduct formation of LOV2 is much smaller than that of LOV1, indicating that reactive and nonreactive forms exist. The conformational changes associated with the excitations of LOV1 and LOV2 occur independently and additively, even when they are excited simultaneously. Hence, the role of LOV1 is not to enhance the kinase activity in addition to LOV2 function; we suggest LOV1 has different functions such as regulation of intermolecular interactions.
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Affiliation(s)
- Yusuke Nakasone
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto , Kyoto 606-8502 , Japan
| | - Masumi Ohshima
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto , Kyoto 606-8502 , Japan
| | - Koji Okajima
- Graduate School of Science and Technology , Keio University , Yokohama , Kanagawa 223-8522 , Japan
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science , Osaka Prefecture University , Sakai , Osaka 599-8531 , Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science , Kyoto University , Kyoto , Kyoto 606-8502 , Japan
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4
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Nakasone Y, Ohshima M, Okajima K, Tokutomi S, Terazima M. Photoreaction Dynamics of LOV1 and LOV2 of Phototropin from Chlamydomonas reinhardtii. J Phys Chem B 2018; 122:1801-1815. [DOI: 10.1021/acs.jpcb.7b10266] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yusuke Nakasone
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Masumi Ohshima
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Koji Okajima
- Graduate
School of Science and Technology, Keio University, Kanagawa 223-8522, Japan
| | - Satoru Tokutomi
- Department
of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahide Terazima
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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5
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Nakajima T, Kuroi K, Nakasone Y, Okajima K, Ikeuchi M, Tokutomi S, Terazima M. Anomalous pressure effects on the photoreaction of a light-sensor protein from Synechocystis, PixD (Slr1694), and the compressibility change of its intermediates. Phys Chem Chem Phys 2018; 18:25915-25925. [PMID: 27711633 DOI: 10.1039/c6cp05091c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
SyPixD (Slr1694) is a blue-light receptor that contains a BLUF (blue-light sensor using a flavin chromophore) domain for the function of phototaxis. The key reaction of this protein is a light-induced conformational change and subsequent dissociation reaction from the decamer to the dimer. In this study, anomalous effects of pressure on this reaction were discovered, and changes in the compressibility of its short-lived intermediates were investigated. While the absorption spectra of the dark and light states are not sensitive to pressure, the formation yield of the first intermediate decreases with pressure to about 40% at 150 MPa. Upon blue-light illumination with a sufficiently strong intensity, the transient grating signal, which represents the dissociation of the SyPixD decamer, was observed at 0.1 MPa, and the signal intensity significantly decreased with increasing pressure. This behavior shows that the dissociation of the decamer from the second intermediate state is suppressed by pressure. However, while the decamer undergoes no dissociation upon excitation of one monomer unit at 0.1 MPa, dissociation is gradually induced with increasing pressure. For solving this strange behavior, the compressibility changes of the intermediates were measured as a function of pressure at weak light intensity. Interestingly, the compressibility change was negative at low pressure, but became positive with increasing pressure. Because the compressibility is related to the volume fluctuation, this observation suggests that the driving force for this reaction is fluctuation of the protein. The relationship between the cavities at the interfaces of the monomer units and the reactivity was also discussed.
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Affiliation(s)
- Tsubasa Nakajima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Kunisato Kuroi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Koji Okajima
- Research Institute for Advanced Science and Technology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahiko Ikeuchi
- Department of Life Sciences (Biology), Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan
| | - Satoru Tokutomi
- Research Institute for Advanced Science and Technology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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6
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Iwata T, Nozaki D, Yamamoto A, Koyama T, Nishina Y, Shiga K, Tokutomi S, Unno M, Kandori H. Hydrogen Bonding Environment of the N3-H Group of Flavin Mononucleotide in the Light Oxygen Voltage Domains of Phototropins. Biochemistry 2017; 56:3099-3108. [PMID: 28530801 DOI: 10.1021/acs.biochem.7b00057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The light oxygen voltage (LOV) domain is a flavin-binding blue-light receptor domain, originally found in a plant photoreceptor phototropin (phot). Recently, LOV domains have been used in optogenetics as the photosensory domain of fusion proteins. Therefore, it is important to understand how LOV domains exhibit light-induced structural changes for the kinase domain regulation, which enables the design of LOV-containing optogenetics tools with higher photoactivation efficiency. In this study, the hydrogen bonding environment of the N3-H group of flavin mononucleotide (FMN) of the LOV2 domain from Adiantum neochrome (neo) 1 was investigated by low-temperature Fourier transform infrared spectroscopy. Using specifically 15N-labeled FMN, [1,3-15N2]FMN, the N3-H stretch was identified at 2831 cm-1 for the unphotolyzed state at 150 K, indicating that the N3-H group forms a fairly strong hydrogen bond. The N3-H stretch showed temperature dependence, with a shift to lower frequencies at ≤200 K and to higher frequencies at ≥250 K from the unphotolyzed to the intermediate states. Similar trends were observed in the LOV2 domains from Arabidopsis phot1 and phot2. By contrast, the N3-H stretch of the Q1029L mutant of neo1-LOV2 and neo1-LOV1 was not temperature dependent in the intermediate state. These results seemed correlated with our previous finding that the LOV2 domains show the structural changes in the β-sheet region and/or the adjacent Jα helix of LOV2 domain, but that such structural changes do not take place in the Q1029L mutant or neo1-LOV1 domain. The environment around the N3-H group was also investigated.
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Affiliation(s)
- Tatsuya Iwata
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Dai Nozaki
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Atsushi Yamamoto
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Takayuki Koyama
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Yasuzo Nishina
- Department of Molecular Physiology, Graduate School of Medical Sciences, Kumamoto University , Honjo, Kumamoto 860-8556, Japan
| | - Kiyoshi Shiga
- Department of Physiology, School of Health Sciences, Kumamoto University , Kuhonji, Kumamoto 862-0976, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University , Sakai, Osaka 599-8531, Japan
| | - Masashi Unno
- Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering, Saga University , Saga 840-8502, Japan
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
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7
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Takakado A, Nakasone Y, Okajima K, Tokutomi S, Terazima M. Light-Induced Conformational Changes of LOV2-Kinase and the Linker Region in Arabidopsis Phototropin2. J Phys Chem B 2017; 121:4414-4421. [DOI: 10.1021/acs.jpcb.7b01552] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Akira Takakado
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yusuke Nakasone
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Koji Okajima
- Department
of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Satoru Tokutomi
- Department
of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahide Terazima
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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8
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Kuroi K, Sato F, Nakasone Y, Zikihara K, Tokutomi S, Terazima M. Time-resolved fluctuation during the photochemical reaction of a photoreceptor protein: phototropin1LOV2-linker. Phys Chem Chem Phys 2017; 18:6228-38. [PMID: 26854261 DOI: 10.1039/c5cp07472j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although the relationship between structural fluctuations and reactions is important for elucidating reaction mechanisms, experimental data describing such fluctuations of reaction intermediates are sparse. In order to investigate structural fluctuations during a protein reaction, the compressibilities of intermediate species after photoexcitation of a phot1LOV2-linker, which is a typical LOV domain protein with the C-terminal linker including the J-α helix and used recently for optogenetics, were measured in the time-domain by the transient grating and transient lens methods with a high pressure optical cell. The yield of covalent bond formation between the chromophore and a Cys residue (S state formation) relative to that at 0.1 MPa decreased very slightly with increasing pressure. The fraction of the reactive species that yields the T state (linker-unfolded state) decreased almost proportionally with pressure (0.1-200 MPa) to about 65%. Interestingly, the volume change associated with the reaction was much more pressure sensitive. By combining these data, the compressibility changes for the short lived intermediate (S state) and the final product (T state) formation were determined. The compressibility of the S state was found to increase compared with the dark (D) state, and the compressibility decreased during the transition from the S state to the T state. The compressibility change is discussed in terms of cavities inside the protein. By comparing the crystal structures of the phot1LOV2-linker at dark and light states, we concluded that the cavity volumes between the LOV domain and the linker domain increase in the S state, which explains the enhanced compressibility.
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Affiliation(s)
- Kunisato Kuroi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Francielle Sato
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| | - Kazunori Zikihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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9
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Yoshitake T, Toyooka T, Nakasone Y, Zikihara K, Tokutomi S, Terazima M. Macromolecular crowding effect for photoreactions of LOV2 domains of Arabidopsis thaliana phototropin 1. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2015.08.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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10
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Takemiya A, Doi A, Yoshida S, Okajima K, Tokutomi S, Shimazaki KI. Reconstitution of an Initial Step of Phototropin Signaling in Stomatal Guard Cells. Plant Cell Physiol 2016; 57:152-159. [PMID: 26707730 DOI: 10.1093/pcp/pcv180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/10/2015] [Indexed: 06/05/2023]
Abstract
Phototropins are light-activated receptor kinases that mediate a wide range of blue light responses responsible for the optimization of photosynthesis. Despite the physiological importance of phototropins, it is still unclear how they transduce light signals into physiological responses. Here, we succeeded in reproducing a primary step of phototropin signaling in vitro using a physiological substrate of phototropin, the BLUS1 (BLUE LIGHT SIGNALING1) kinase of guard cells. When PHOT1 and BLUS1 were expressed in Escherichia coli and the resulting recombinant proteins were incubated with ATP, white and blue light induced phosphorylation of BLUS1 but red light and darkness did not. Site-directed mutagenesis of PHOT1 and BLUS1 revealed that the phosphorylation was catalyzed by phot1 kinase. Similar to stomatal blue light responses, the BLUS1 phosphorylation depended on the fluence rate of blue light and was inhibited by protein kinase inhibitors, K-252a and staurosporine. In contrast to the result in vivo, BLUS1 was not dephosphorylated in vitro, suggesting the involvement of a protein phosphatase in the response in vivo. phot1 with a C-terminal kinase domain but devoid of the N-terminal domain, constitutively phosphorylated BLUS1 without blue light, indicating that the N-terminal domain has an autoinhibitory action and prevents substrate phosphorylation. The results provide the first reconstitution of a primary step of phototropin signaling and a clue for understanding the molecular nature of this process.
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Affiliation(s)
- Atsushi Takemiya
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
| | - Ayaka Doi
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
| | - Sayumi Yoshida
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
| | - Koji Okajima
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-851 Japan Present address: Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa, 223-8522 Japan.
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-851 Japan
| | - Ken-Ichiro Shimazaki
- Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395 Japan
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11
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Kashojiya S, Yoshihara S, Okajima K, Tokutomi S. The linker between LOV2-Jα and STK plays an essential role in the kinase activation by blue light in Arabidopsis phototropin1, a plant blue light receptor. FEBS Lett 2015; 590:139-47. [PMID: 26763121 DOI: 10.1002/1873-3468.12028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 11/25/2015] [Accepted: 11/26/2015] [Indexed: 11/07/2022]
Abstract
Phototropin (phot), a blue light receptor in plants, is composed of several domains: LOV1, LOV2, and a serine/threonine kinase (STK). LOV2 is the main regulator of light activation of STK. However, the detailed mechanism remains unclear. In this report, we focused on the linker region between LOV2 and STK excluding the Jα-helix. Spectroscopy and a kinase assay for the substituents in the linker region of Arabidopsis phot1 LOV2-STK indicated that the linker is involved in the activation of STK. A putative module in the middle of the linker would be critical for intramolecular signaling and/or regulation of STK.
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Affiliation(s)
- Sachiko Kashojiya
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Shizue Yoshihara
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Koji Okajima
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
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12
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Kashojiya S, Okajima K, Shimada T, Tokutomi S. Essential role of the A'α/Aβ gap in the N-terminal upstream of LOV2 for the blue light signaling from LOV2 to kinase in Arabidopsis photototropin1, a plant blue light receptor. PLoS One 2015; 10:e0124284. [PMID: 25886203 PMCID: PMC4401697 DOI: 10.1371/journal.pone.0124284] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/12/2015] [Indexed: 11/18/2022] Open
Abstract
Phototropin (phot) is a blue light (BL) receptor in plants and is involved in phototropism, chloroplast movement, stomata opening, etc. A phot molecule has two photo-receptive domains named LOV (Light-Oxygen-Voltage) 1 and 2 in its N-terminal region and a serine/threonine kinase (STK) in its C-terminal region. STK activity is regulated mainly by LOV2, which has a cyclic photoreaction, including the transient formation of a flavin mononucleotide (FMN)-cysteinyl adduct (S390). One of the key events for the propagation of the BL signal from LOV2 to STK is conformational changes in a Jα-helix residing downstream of the LOV2 C-terminus. In contrast, we focused on the role of the A’α-helix, which is located upstream of the LOV2 N-terminus and interacts with the Jα-helix. Using LOV2-STK polypeptides from Arabidopsis thaliana phot1, we found that truncation of the A’α-helix and amino acid substitutions at Glu474 and Lys475 in the gap between the A’α and the Aβ strand of LOV2 (A’α/Aβ gap) to Ala impaired the BL-induced activation of the STK, although they did not affect S390 formation. Trypsin digested the LOV2-STK at Lys603 and Lys475 in a light-dependent manner indicating BL-induced structural changes in both the Jα-helix and the gap. The digestion at Lys603 is faster than at Lys475. These BL-induced structural changes were observed with the Glu474Ala and the Lys475Ala substitutes, indicating that the BL signal reached the Jα-helix as well as the A’α/Aβ gap but could not activate STK. The amino acid residues, Glu474 and Lys475, in the gap are conserved among the phots of higher plants and may act as a joint to connect the structural changes in the Jα-helix with the activation of STK.
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Affiliation(s)
- Sachiko Kashojiya
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Koji Okajima
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
- * E-mail:
| | - Takashi Shimada
- Life Science Research Center, SHIMADZU Corporation, Tokyo, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Osaka Prefecture University, Sakai, Osaka, Japan
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13
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Kuroi K, Okajima K, Ikeuchi M, Tokutomi S, Kamiyama T, Terazima M. Pressure-Sensitive Reaction Yield of the TePixD Blue-Light Sensor Protein. J Phys Chem B 2015; 119:2897-907. [DOI: 10.1021/jp511946u] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Kunisato Kuroi
- Department of Chemistry, Graduate School
of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Koji Okajima
- Department of Life Sciences (Biology),
Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan
- Department
of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai,
Osaka 599-8531, Japan
| | - Masahiko Ikeuchi
- Department of Life Sciences (Biology),
Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan
| | - Satoru Tokutomi
- Department
of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai,
Osaka 599-8531, Japan
| | - Tadashi Kamiyama
- Department of Chemistry, School of Science and Engineering, Kinki University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School
of Science, Kyoto University, Kyoto 606-8502, Japan
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14
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Yoshitake Y, Yokoo T, Saito H, Tsukiyama T, Quan X, Zikihara K, Katsura H, Tokutomi S, Aboshi T, Mori N, Inoue H, Nishida H, Kohchi T, Teraishi M, Okumoto Y, Tanisaka T. The effects of phytochrome-mediated light signals on the developmental acquisition of photoperiod sensitivity in rice. Sci Rep 2015; 5:7709. [PMID: 25573482 PMCID: PMC4287723 DOI: 10.1038/srep07709] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 12/08/2014] [Indexed: 11/30/2022] Open
Abstract
Plants commonly rely on photoperiodism to control flowering time. Rice development before floral initiation is divided into two successive phases: the basic vegetative growth phase (BVP, photoperiod-insensitive phase) and the photoperiod-sensitive phase (PSP). The mechanism responsible for the transition of rice plants into their photoperiod-sensitive state remains elusive. Here, we show that se13, a mutation detected in the extremely early flowering mutant X61 is a nonsense mutant gene of OsHY2, which encodes phytochromobilin (PΦB) synthase, as evidenced by spectrometric and photomorphogenic analyses. We demonstrated that some flowering time and circadian clock genes harbor different expression profiles in BVP as opposed to PSP, and that this phenomenon is chiefly caused by different phytochrome-mediated light signal requirements: in BVP, phytochrome-mediated light signals directly suppress Ehd2, while in PSP, phytochrome-mediated light signals activate Hd1 and Ghd7 expression through the circadian clock genes' expression. These findings indicate that light receptivity through the phytochromes is different between two distinct developmental phases corresponding to the BVP and PSP in the rice flowering process. Our results suggest that these differences might be involved in the acquisition of photoperiod sensitivity in rice.
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Affiliation(s)
- Yoshihiro Yoshitake
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Takayuki Yokoo
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Hiroki Saito
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Takuji Tsukiyama
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Xu Quan
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Kazunori Zikihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Hitomi Katsura
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Takako Aboshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Naoki Mori
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Hiromo Inoue
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Hidetaka Nishida
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Takayuki Kohchi
- Graduate School of Biostudies, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Masayoshi Teraishi
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Yutaka Okumoto
- Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Takatoshi Tanisaka
- 1] Division of Agronomy and Horticulture Science, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan [2] Department of Agricultural Regional Vitalization, Kibi International University, Minamiawaji, Hyogo, 656-0484, Japan
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15
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Sharma S, Kharshiing E, Srinivas A, Zikihara K, Tokutomi S, Nagatani A, Fukayama H, Bodanapu R, Behera RK, Sreelakshmi Y, Sharma R. A dominant mutation in the light-oxygen and voltage2 domain vicinity impairs phototropin1 signaling in tomato. Plant Physiol 2014; 164:2030-2044. [PMID: 24515830 PMCID: PMC3982760 DOI: 10.1104/pp.113.232306] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 02/09/2014] [Indexed: 05/29/2023]
Abstract
In higher plants, blue light (BL) phototropism is primarily controlled by the phototropins, which are also involved in stomatal movement and chloroplast relocation. These photoresponses are mediated by two phototropins, phot1 and phot2. Phot1 mediates responses with higher sensitivity than phot2, and phot2 specifically mediates chloroplast avoidance and dark positioning responses. Here, we report the isolation and characterization of a Nonphototropic seedling1 (Nps1) mutant of tomato (Solanum lycopersicum). The mutant is impaired in low-fluence BL responses, including chloroplast accumulation and stomatal opening. Genetic analyses show that the mutant locus is dominant negative in nature. In dark-grown seedlings of the Nps1 mutant, phot1 protein accumulates at a highly reduced level relative to the wild type and lacks BL-induced autophosphorylation. The mutant harbors a single glycine-1484-to-alanine transition in the Hinge1 region of a phot1 homolog, resulting in an arginine-to-histidine substitution (R495H) in a highly conserved A'α helix proximal to the light-oxygen and voltage2 domain of the translated gene product. Significantly, the R495H substitution occurring in the Hinge1 region of PHOT1 abolishes its regulatory activity in Nps1 seedlings, thereby highlighting the functional significance of the A'α helix region in phototropic signaling of tomato.
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16
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Kuroi K, Tanaka K, Okajima K, Ikeuchi M, Tokutomi S, Terazima M. Anomalous diffusion of TePixD and identification of the photoreaction product. Photochem Photobiol Sci 2014; 12:1180-6. [PMID: 23535998 DOI: 10.1039/c3pp25434h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
TePixD is a blue-light sensor protein from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 (TePixD Tll0078). Although the photochemistry has been examined, so far the photoproduct remains unknown. We have measured the diffusion coefficient (D) of TePixD in the dark by dynamic light scattering and have discovered a very peculiar diffusion property; the decamer oligomer has a larger D than that of the pentamer. Furthermore, D of the pentamer was found to be very close to that of the TePixD decamer photoreaction product. In order to investigate this reaction further, elution profiles of size-exclusion chromatography were measured under dark and illuminated conditions at low (40 μM) and high (1.1 mM) TePixD concentrations. On the basis of these results, we have concluded that the main photoreaction of the TePixD decamer is the dissociation into the pentamer. The secondary structure change associated with this reaction was found to be minor according to circular dichroism analysis.
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Affiliation(s)
- Kunisato Kuroi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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17
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Nakasone Y, Zikihara K, Tokutomi S, Terazima M. Photochemistry of Arabidopsis phototropin 1 LOV1: transient tetramerization. Photochem Photobiol Sci 2014; 12:1171-9. [PMID: 23743549 DOI: 10.1039/c3pp50047k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photochemical reaction of the LOV1 (light-oxygen-voltage 1) domain of phototropin 1 from Arabidopsis thaliana was investigated by the time-resolved transient grating method. As with other LOV domains, an absorption spectral change associated with an adduct formation between its chromophore (flavin mononucleotide) and a cysteine residue was observed with a time constant of 1.1 μs. After this reaction, a significant diffusion coefficient (D) change (D of the reactant = 8.2 × 10(-11) m(2) s(-1), and D of the photoproduct = 6.4 × 10(-11) m(2) s(-1)) was observed with a time constant of 14 ms at a protein concentration of 270 μM. From the D value of the ground state and the peak position in size exclusion chromatography, we have confirmed that the phot1LOV1 domain exists as a dimer in the dark. The D-value and the concentration dependence of the rate indicated that the phot1LOV1 domain associates to form a tetramer (dimerization of the dimer) upon photoexcitation. We also found that the chromophore is released from the binding pocket of the LOV domain when it absorbs two photons within a pulse duration, which occurs in addition to the normal photocycle reaction. On the basis of these results, we discuss the molecular mechanism of the light dependent role of the phot1LOV1 domain.
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Affiliation(s)
- Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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18
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Okajima K, Aihara Y, Takayama Y, Nakajima M, Kashojiya S, Hikima T, Oroguchi T, Kobayashi A, Sekiguchi Y, Yamamoto M, Suzuki T, Nagatani A, Nakasako M, Tokutomi S. Light-induced conformational changes of LOV1 (light oxygen voltage-sensing domain 1) and LOV2 relative to the kinase domain and regulation of kinase activity in Chlamydomonas phototropin. J Biol Chem 2014; 289:413-22. [PMID: 24285544 PMCID: PMC3879564 DOI: 10.1074/jbc.m113.515403] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/25/2013] [Indexed: 01/27/2023] Open
Abstract
Phototropin (phot), a blue light (BL) receptor in plants, has two photoreceptive domains named LOV1 and LOV2 as well as a Ser/Thr kinase domain (KD) and acts as a BL-regulated protein kinase. A LOV domain harbors a flavin mononucleotide that undergoes a cyclic photoreaction upon BL excitation via a signaling state in which the inhibition of the kinase activity by LOV2 is negated. To understand the molecular mechanism underlying the BL-dependent activation of the kinase, the photochemistry, kinase activity, and molecular structure were studied with the phot of Chlamydomonas reinhardtii. Full-length and LOV2-KD samples of C. reinhardtii phot showed cyclic photoreaction characteristics with the activation of LOV- and BL-dependent kinase. Truncation of LOV1 decreased the photosensitivity of the kinase activation, which was well explained by the fact that the signaling state lasted for a shorter period of time compared with that of the phot. Small angle x-ray scattering revealed monomeric forms of the proteins in solution and detected BL-dependent conformational changes, suggesting an extension of the global molecular shapes of both samples. Constructed molecular model of full-length phot based on the small angle x-ray scattering data proved the arrangement of LOV1, LOV2, and KD for the first time that showed a tandem arrangement both in the dark and under BL irradiation. The models suggest that LOV1 alters its position relative to LOV2-KD under BL irradiation. This finding demonstrates that LOV1 may interact with LOV2 and modify the photosensitivity of the kinase activation through alteration of the duration of the signaling state in LOV2.
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Affiliation(s)
- Koji Okajima
- From the Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Yusuke Aihara
- the Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan, and
| | - Yuki Takayama
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
- the Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Mihoko Nakajima
- From the Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Sachiko Kashojiya
- From the Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Takaaki Hikima
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Tomotaka Oroguchi
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
- the Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Amane Kobayashi
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
- the Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Yuki Sekiguchi
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
- the Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Masaki Yamamoto
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Tomomi Suzuki
- the Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan, and
| | - Akira Nagatani
- the Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan, and
| | - Masayoshi Nakasako
- RIKEN Harima Institute, SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
- the Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Satoru Tokutomi
- From the Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
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19
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Takeda K, Nakasone Y, Zikihara K, Tokutomi S, Terazima M. Dynamics of the amino-terminal and carboxyl-terminal helices of Arabidopsis phototropin 1 LOV2 studied by the transient grating. J Phys Chem B 2013; 117:15606-13. [PMID: 23931584 DOI: 10.1021/jp406109j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently, conformational changes of the amino-terminal helix (A'α helix), in addition to the reported conformational changes of the carboxyl-terminal helix (Jα helix), have been proposed to be important for the regulatory function of the light-oxygen-voltage 2 domain (LOV2) of phototropin 1 from Arabidopsis. However, the reaction dynamics of the A'α helix have not been examined. Here, the unfolding reactions of the A'α and Jα helices of the LOV2 domain of phototropin 1 from Arabidopsis thaliana were investigated by the time-resolved transient grating (TG) method. A mutant (T469I mutant) that renders the A'α helix unfolded in the dark state showed unfolding of the Jα helix with a time constant of 1 ms, which is very similar to the time constant reported for the wild-type LOV2-linker sample. Furthermore, a mutant (I608E mutant) that renders the Jα helix unfolded in the dark state exhibited an unfolding process of the A'α helix with a time constant of 12 ms. On the basis of these experimental results, it is suggested that the unfolding reactions of these helices occurs independently.
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Affiliation(s)
- Kimitoshi Takeda
- Department of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa, Kyoto 606-8502, Japan
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20
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21
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Mori H, Tone Y, Shimizu K, Zikihara K, Tokutomi S, Ida T, Ihara H, Hara M. Studies on fish scale collagen of Pacific saury (Cololabis saira). Materials Science and Engineering: C 2013; 33:174-81. [DOI: 10.1016/j.msec.2012.08.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/14/2012] [Accepted: 08/12/2012] [Indexed: 11/27/2022]
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22
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Hisatomi O, Takeuchi K, Zikihara K, Ookubo Y, Nakatani Y, Takahashi F, Tokutomi S, Kataoka H. Blue Light-Induced Conformational Changes in a Light-Regulated Transcription Factor, Aureochrome-1. ACTA ACUST UNITED AC 2012; 54:93-106. [DOI: 10.1093/pcp/pcs160] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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23
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Okajima K, Kashojiya S, Tokutomi S. Photosensitivity of kinase activation by blue light involves the lifetime of a cysteinyl-flavin adduct intermediate, S390, in the photoreaction cycle of the LOV2 domain in phototropin, a plant blue light receptor. J Biol Chem 2012; 287:40972-81. [PMID: 23066024 DOI: 10.1074/jbc.m112.406512] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phototropin (phot) is a light-regulated protein kinase that mediates a variety of photoresponses in plants, such as phototropism, chloroplast positioning, and stomata opening. Arabidopsis has two homologues, phot1 and phot2, that share physiological functions depending on light intensity. A phot molecule has two photoreceptive light oxygen voltage-sensing domains, LOV1 and LOV2, and a Ser/Thr kinase domain. The LOV domains undergo a photocycle upon blue light (BL) stimulation, including transient adduct formation between the chromophore and a conserved cysteine (S390 intermediate) that leads to activation of the kinase. To uncover the mechanism underlying the photoactivation of the kinase, we have introduced a kinase assay system composed of a phot1 LOV2-linker-kinase polypeptide as a light-regulated kinase and its N-terminal polypeptide as an artificial substrate (Okajima, K., Matsuoka, D., and Tokutomi, S. (2011) LOV2-linker-kinase phosphorylates LOV1-containing N-terminal polypeptide substrate via photoreaction of LOV2 in Arabidopsis phototropin1. FEBS Lett. 585, 3391-3395). In the present study, we extended the assay system to phot2 and compared the photochemistry and kinase activation by BL between phot1 and phot2 to gain insight into the molecular basis for the different photosensitivities of phot1 and phot2. Photosensitivity of kinase activation by BL and the lifetime of S390 of phot1 were 10 times higher and longer, respectively, than those of phot2. This correlation was confirmed by an amino acid substitution experiment with phot1 to shorten the lifetime of S390. The present results demonstrated that the photosensitivity of kinase activation in phot involves the lifetime of S390 in LOV2, suggesting that the lifetime is one of the key factors for the different photosensitivities observed for phot1 and phot2.
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Affiliation(s)
- Koji Okajima
- Department of Biological Sciences, Graduate School of Science, Osaka Prefecture University, Gakuen-cho 1-1, Nakaku, Sakai, Osaka 599-8531, Japan
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24
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Tanaka K, Nakasone Y, Okajima K, Ikeuchi M, Tokutomi S, Terazima M. Time-Resolved Tracking of Interprotein Signal Transduction: Synechocystis PixD–PixE Complex as a Sensor of Light Intensity. J Am Chem Soc 2012; 134:8336-9. [DOI: 10.1021/ja301540r] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Keisuke Tanaka
- Department of Chemistry, Graduate
School of Science, Kyoto University, Kyoto
606-8502, Japan
| | - Yusuke Nakasone
- Department of Chemistry, Graduate
School of Science, Kyoto University, Kyoto
606-8502, Japan
| | - Koji Okajima
- Department
of Life Sciences
(Biology), Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan
- Department of Biological Science,
Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahiko Ikeuchi
- Department
of Life Sciences
(Biology), Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan
| | - Satoru Tokutomi
- Department of Biological Science,
Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate
School of Science, Kyoto University, Kyoto
606-8502, Japan
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25
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Aihara Y, Yamamoto T, Okajima K, Yamamoto K, Suzuki T, Tokutomi S, Tanaka K, Nagatani A. Mutations in N-terminal flanking region of blue light-sensing light-oxygen and voltage 2 (LOV2) domain disrupt its repressive activity on kinase domain in the Chlamydomonas phototropin. J Biol Chem 2012; 287:9901-9909. [PMID: 22291022 PMCID: PMC3322977 DOI: 10.1074/jbc.m111.324723] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 01/26/2012] [Indexed: 11/06/2022] Open
Abstract
Phototropin is a light-regulated kinase that mediates a variety of photoresponses such as phototropism, chloroplast positioning, and stomata opening in plants to increase the photosynthetic efficiency. Blue light stimulus first induces local conformational changes in the chromophore-bearing light-oxygen and voltage 2 (LOV2) domain of phototropin, which in turn activates the serine/threonine (Ser/Thr) kinase domain in the C terminus. To examine the kinase activity of full-length phototropin conventionally, we employed the budding yeast Saccharomyces cerevisiae. In this organism, Ser/Thr kinases (Fpk1p and Fpk2p) that show high sequence similarity to the kinase domain of phototropins exist. First, we demonstrated that the phototropin from Chlamydomonas reinhardtii (CrPHOT) could complement loss of Fpk1p and Fpk2p to allow cell growth in yeast. Furthermore, this reaction was blue light-dependent, indicating that CrPHOT was indeed light-activated in yeast cells. We applied this system to a large scale screening for amino acid substitutions in CrPHOT that elevated the kinase activity in darkness. Consequently, we identified a cluster of mutations located in the N-terminal flanking region of LOV2 (R199C, L202L, D203N/G/V, L204P, T207I, and R210H). An in vitro phosphorylation assay confirmed that these mutations substantially reduced the repressive activity of LOV2 on the kinase domain in darkness. Furthermore, biochemical analyses of the representative T207I mutant demonstrated that the mutation affected neither spectral nor multimerization properties of CrPHOT. Hence, the N-terminal flanking region of LOV2, as is the case with the C-terminal flanking Jα region, appears to play a crucial role in the regulation of kinase activity in phototropin.
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Affiliation(s)
- Yusuke Aihara
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Takaharu Yamamoto
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo 060-0815, Japan, and
| | - Koji Okajima
- Department of Biological Sciences, Graduate School of Science, Osaka Prefecture University, Osaka 599-8531, Japan
| | - Kazuhiko Yamamoto
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Tomomi Suzuki
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Satoru Tokutomi
- Department of Biological Sciences, Graduate School of Science, Osaka Prefecture University, Osaka 599-8531, Japan
| | - Kazuma Tanaka
- Division of Molecular Interaction, Institute for Genetic Medicine, Hokkaido University Graduate School of Life Science, Sapporo 060-0815, Japan, and
| | - Akira Nagatani
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan,.
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26
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Iwata T, Tokutomi S, Kandori H. Light-induced structural changes of the LOV2 domains in various phototropins revealed by FTIR spectroscopy. Biophysics (Nagoya-shi) 2011; 7:89-98. [PMID: 27857596 PMCID: PMC5036776 DOI: 10.2142/biophysics.7.89] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 09/08/2011] [Indexed: 12/01/2022] Open
Abstract
Phototropin (Phot), a blue-light photoreceptor in plants, consists of two FMN-binding domains (named LOV1 and LOV2) and a serine/threonine (Ser/Thr) kinase domain. We have investigated light-induced structural changes of LOV domains, which lead to the activation of the kinase domain, by means of light-induced difference FTIR spectroscopy. FTIR spectroscopy revealed that the reactive cysteine is protonated in both unphotolyzed and triplet-excited states, which is difficult to detect by other methods such as X-ray crystallography. In this review, we describe the light-induced structural changes of hydrogen-bonding environment of FMN chromophore and protein backbone in Adiantum neo1-LOV2 in the C=O stretching region by use of 13C-labeled samples. We also describe the comprehensive FTIR analysis of LOV2 domains among Arabidopsis phot1, phot2, and Adiantum neo1 with and without Jα helix domain.
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Affiliation(s)
- Tatsuya Iwata
- Center for Fostering Young and Innovative Researchers, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan; Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Satoru Tokutomi
- Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Hideki Kandori
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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27
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Okajima K, Matsuoka D, Tokutomi S. LOV2-linker-kinase phosphorylates LOV1-containing N-terminal polypeptide substrate via photoreaction of LOV2 in Arabidopsis phototropin1. FEBS Lett 2011; 585:3391-5. [PMID: 22001205 DOI: 10.1016/j.febslet.2011.10.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 10/02/2011] [Accepted: 10/03/2011] [Indexed: 12/30/2022]
Abstract
Phototropin is a blue light receptor in plants and is thought to be a light-regulated protein kinase. Previously, we defined the role of the photoreceptive domains, LOV1 and 2, in the light activation of the kinase in Arabidopsis phototropin2 (phot2). In this study, photoregulation of the kinase in phototropin1 (phot1) was studied using LOV2-linker-kinase polypeptide. We designed a new substrate consisting of the N-terminal part of the phot1 with autophosphorylation sites. The LOV2-linker-kinase had the same spectroscopic properties as those of the LOV2 core and phosphorylated the substrate in a light-dependent manner. Amino acid substitution experiments proved that the phosphorylation comes from the activation of the kinase via photoreaction of LOV2.
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Affiliation(s)
- Koji Okajima
- Department of Biological Sciences, Graduate School of Science, Osaka Prefecture University, Gakuen-cho 1-1, Nakaku, Sakai, Osaka 599-8531, Japan
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Nakasone Y, Zikihara K, Tokutomi S, Terazima M. Kinetics of conformational changes of the FKF1-LOV domain upon photoexcitation. Biophys J 2011; 99:3831-9. [PMID: 21112308 DOI: 10.1016/j.bpj.2010.10.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 10/01/2010] [Accepted: 10/06/2010] [Indexed: 01/16/2023] Open
Abstract
The photochemical reaction dynamics of a light-oxygen-voltage (LOV) domain from the blue light sensor protein, FKF1 (flavin-binding Kelch repeat F-box) was studied by means of the pulsed laser-induced transient grating method. The observed absorption spectral changes upon photoexcitation were similar to the spectral changes observed for typical LOV domain proteins (e.g., phototropins). The adduct formation took place with a time constant of 6 μs. After this reaction, a significant conformational change with a time constant of 6 ms was observed as a change in the diffusion coefficient. An FKF1-LOV mutant without the conserved loop connecting helices E and F, which is present only in the FKF1/LOV Kelch protein 2/ZEITLUPE family, did not show these slow phase dynamics. This result indicates that the conformational change in the loop region represents a major change in the FKF1-LOV photoreaction.
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Affiliation(s)
- Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
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29
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Takayama Y, Nakasako M, Okajima K, Iwata A, Kashojiya S, Matsui Y, Tokutomi S. Light-Induced Movement of the LOV2 Domain in an Asp720Asn Mutant LOV2−Kinase Fragment of Arabidopsis Phototropin 2. Biochemistry 2011; 50:1174-83. [DOI: 10.1021/bi101689b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Yuki Takayama
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
- The RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Masayoshi Nakasako
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
- The RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Koji Okajima
- The Department of Biological Science, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan
| | - Aya Iwata
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
| | - Sachiko Kashojiya
- The Department of Biological Science, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan
| | - Yuka Matsui
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan
- The RIKEN Harima Institute/SPring-8, 1-1-1 Kouto, Mikaduki, Sayo, Hyogo 679-5148, Japan
| | - Satoru Tokutomi
- The Department of Biological Science, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan
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Abstract
To reveal macromolecular crowding effects on a chemical reaction of a BLUF (sensors of blue light using FAD) protein (PixD from a thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 [TePixD, Tll0078]), the photoreaction was studied at various concentrations of the macromolecule Ficoll-70 by UV/Vis absorption spectroscopy and the pulsed laser-induced transient grating (TG) method. The absorption spectrum did not change with varying concentration of Ficoll-70. The crowding did not affect the quantum yield of the spectral red shift reaction, recovery rate of the product, rate constant of the volume change reaction and the magnitude of the volume change. However, the magnitude of the TG signal representing the diffusion-sensitive conformation change significantly increased on addition of Ficoll-70. This dependence was attributed to the crowding effect on the TePixD decamer-pentamer equilibrium in the solution. This result indicates that the TePixD reaction is more efficient in cellular than in in vitro conditions.
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Affiliation(s)
- Tsuguyoshi Toyooka
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
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31
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Kawaguchi Y, Nakasone Y, Zikihara K, Tokutomi S, Terazima M. When is the helix conformation restored after the reverse reaction of phototropin? J Am Chem Soc 2010; 132:8838-9. [PMID: 20536129 DOI: 10.1021/ja1020519] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Following the disruption of the covalent bond between the cysteine and flavin of Phot1LOV2-linker, the unfolded conformation of the linker folds with a time constant of 13 ms, which is considerably (approximately 10(4) times) slower than the helix formation rate measured for an alpha-helical polypeptide in solution.
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Affiliation(s)
- Yuki Kawaguchi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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32
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Kikuchi S, Unno M, Zikihara K, Tokutomi S, Yamauchi S. Vibrational assignment of the flavin-cysteinyl adduct in a signaling state of the LOV domain in FKF1. J Phys Chem B 2009; 113:2913-21. [PMID: 19708118 DOI: 10.1021/jp808399f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
LOV domains belong to the PAS domain superfamily, which are found in a variety of sensor proteins in organism ranging from archaea to eukaryotes, and they noncovalently bind a single flavin mononucleotide as a chromophore. We report the Raman spectra of the dark state of LOV domain in FKF1 from Arabidopsis thaliana. Spectra have been also measured for the signaling state, where a cysteinyl-flavin adduct is formed upon light irradiation. Most of the observed Raman bands are assigned on the basis of normal mode calculations using a density functional theory. We also discuss implication for the analysis of the infrared spectra of LOV domains. The comprehensive assignment provides a satisfactory framework for future investigations of the photocycle mechanism in LOV domains by vibrational spectroscopy.
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Affiliation(s)
- Sadato Kikuchi
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
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33
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Tanaka K, Nakasone Y, Okajima K, Ikeuchi M, Tokutomi S, Terazima M. Oligomeric-state-dependent conformational change of the BLUF protein TePixD (Tll0078). J Mol Biol 2009; 386:1290-300. [PMID: 19452599 DOI: 10.1016/j.jmb.2009.01.026] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The photochemical reaction dynamics of a BLUF (sensors of blue light using FAD) protein, PixD, from a thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 (TePixD, Tll0078) were studied by pulsed laser-induced transient grating method. After the formation of an intermediate species with a red-shifted absorption spectrum, two new reaction phases reflecting protein conformational changes were discovered; one reaction phase manifested itself as expansion of partial molar volume with a time constant of 40 micros, whereas the other reaction phase represented a change in the diffusion coefficient D [i.e., the diffusion-sensitive conformational change (DSCC)]. D decreased from 4.9 x 10(-11) to 4.4 x 10(-11) m2 s(-1) upon the formation of the first intermediate, and subsequently showed a more pronounced decrease to 3.2 x 10(-11) m2 s(-1) upon formation of the second intermediate. From a global analysis of signals at various grating wavenumbers, the time constant of D-change was determined to be 4 ms. Although the magnitude and rate constant of the faster volume change were independent of protein concentration, the amplitude of the signal that reflects the later DSCC significantly decreased as the protein concentration decreased. This concentration dependence suggests that two species exist in solution: a reactive species exhibiting the DSCC, and a second species that is nonreactive. The fraction of these species was found to be dependent on the concentration. The difference in reactivity was attributed to the different oligomeric states of TePixD (i.e., pentamer and decamer). The equilibrium of these states in the dark was confirmed by size-exclusion chromatography at various concentrations. These results demonstrated that only the decamer state is responsible for the conformational change. The results may suggest that the oligomeric state is functionally important in the signal transduction of this photosensory protein.
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Affiliation(s)
- Keisuke Tanaka
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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34
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Koyama T, Iwata T, Yamamoto A, Sato Y, Matsuoka D, Tokutomi S, Kandori H. Different Role of the Jα Helix in the Light-Induced Activation of the LOV2 Domains in Various Phototropins. Biochemistry 2009; 48:7621-8. [DOI: 10.1021/bi9009192] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Takayuki Koyama
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Tatsuya Iwata
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Atsushi Yamamoto
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Yoshiaki Sato
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Daisuke Matsuoka
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Hideki Kandori
- Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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35
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Pfeifer A, Majerus T, Zikihara K, Matsuoka D, Tokutomi S, Heberle J, Kottke T. Time-resolved Fourier transform infrared study on photoadduct formation and secondary structural changes within the phototropin LOV domain. Biophys J 2009; 96:1462-70. [PMID: 19217862 DOI: 10.1016/j.bpj.2008.11.016] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Accepted: 11/06/2008] [Indexed: 10/21/2022] Open
Abstract
Phototropins are plant blue-light photoreceptors containing two light-, oxygen-, or voltage-sensitive (LOV) domains and a C-terminal kinase domain. The two LOV domains bind noncovalently flavin mononucleotide as a chromophore. We investigated the photocycle of fast-recovery mutant LOV2-I403V from Arabidopsis phototropin 2 by step-scan Fourier transform infrared spectroscopy. The reaction of the triplet excited state of flavin with cysteine takes place with a time constant of 3 micros to yield the covalent adduct. Our data provide evidence that the flavin is unprotonated in the productive triplet state, disfavoring an ionic mechanism of bond formation. An intermediate adduct species was evident that displayed changes in secondary structure in the helix or loop region, and relaxed with a time constant of 120 micros. In milliseconds, the final adduct state is formed by further alterations of secondary structure, including beta-sheets. A comparison with wild-type adduct spectra shows that the mutation does not interfere with the functionality of the domain. All signals originate from within the LOV domain, because the construct does not comprise the adjacent Jalpha helix required for signal transduction. The contribution of early and late adduct intermediates to signal transfer to the Jalpha helix outside of the domain is discussed.
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Affiliation(s)
- Anna Pfeifer
- Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
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Katsura H, Zikihara K, Okajima K, Yoshihara S, Tokutomi S. Oligomeric structure of LOV domains in Arabidopsis phototropin. FEBS Lett 2009; 583:526-30. [PMID: 19166850 DOI: 10.1016/j.febslet.2009.01.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 12/25/2008] [Accepted: 01/07/2009] [Indexed: 11/30/2022]
Abstract
Oligomeric structures of the four LOV domains in Arabidopsis phototropin1 (phot1) and 2 (phot2) were studied using crosslinking. Both LOV1 domains of phot1 and phot2 form a dimer independently on the light conditions, suggesting that the LOV1 domain can be a stable dimerization site of phot in vivo. In contrast, phot1-LOV2 is in a monomer-dimer equilibrium and phot2-LOV2 exists as a monomer in the dark. Blue light-induced a slight increase in the monomer population in phot1-LOV2, suggesting a possible blue light-inducible dissociation of dimers. Furthermore, blue light caused a band shift of the phot2-LOV2 monomer. CD spectra revealed the unfolding of helices and the formation of strand structures. Both light-induced changes were reversible in the dark.
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Affiliation(s)
- Hitomi Katsura
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Naka-ku, Sakai, Osaka, Japan
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37
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Ogura Y, Tokutomi S, Wada M, Kiyosue T. PAS/LOV proteins: A proposed new class of plant blue light receptor. Plant Signal Behav 2008; 3:966-8. [PMID: 19704421 PMCID: PMC2633744 DOI: 10.4161/psb.6150] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Accepted: 04/18/2008] [Indexed: 05/23/2023]
Abstract
The light, oxygen or voltage (LOV) domain belongs to the Per-ARNT-Sim (PAS) superfamily of domains, and functions with the flavin chromophore as a module for sensing blue light in plants and fungi. The Arabidopsis thaliana PAS/LOV proteins (PLPs), of unknown function, possess an N-terminal PAS domain and a C-terminal LOV domain. Our recent analysis using yeast two-hybrid and Escherichia coli protein production systems reveals that the interactions of Arabidopsis PLPs with several proteins diminish under blue light illumination and that the PLP LOV domain may bind to a flavin chromophore. These results suggest that PLP functions as a blue light receptor. Homologs of PLP exist in rice, tomato and moss. The LOV domains of these PLP homologs form a distinct group in phylogenetic analysis. These facts suggest that PLP belongs to a new class of plant blue light receptor.
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Affiliation(s)
- Yasunobu Ogura
- Division of Genome Analysis and Genetic Research; Life Science Research Center; Institute of Research Promotion; Kagawa University; Kagawa Japan
| | - Satoru Tokutomi
- Department of Biological Science; Graduate School of Science; Osaka Prefecture University; Osaka, Japan
| | - Masamitsu Wada
- Department of Biology; Faculty of Science; Kyushu Univeristy; Fukuoka Japan
| | - Tomohiro Kiyosue
- Division of Genome Analysis and Genetic Research; Life Science Research Center; Institute of Research Promotion; Kagawa University; Kagawa Japan
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38
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Nakasone Y, Eitoku T, Zikihara K, Matsuoka D, Tokutomi S, Terazima M. Stability of Dimer and Domain–Domain Interaction of Arabidopsis Phototropin 1 LOV2. J Mol Biol 2008; 383:904-13. [DOI: 10.1016/j.jmb.2008.08.074] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 08/25/2008] [Accepted: 08/30/2008] [Indexed: 10/21/2022]
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Nakasako M, Zikihara K, Matsuoka D, Katsura H, Tokutomi S. Structural Basis of the LOV1 Dimerization of Arabidopsis Phototropins 1 and 2. J Mol Biol 2008; 381:718-33. [DOI: 10.1016/j.jmb.2008.06.033] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 06/09/2008] [Accepted: 06/11/2008] [Indexed: 01/18/2023]
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Nakasako M, Hirata M, Shimizu N, Hosokawa S, Matsuoka D, Oka T, Yamamoto M, Tokutomi S. Crystallization and preliminary X-ray diffraction analysis [correction of anaylsis] of the LOV1 domains of phototropin 1 and 2 from Arabidopsis thaliana. Acta Crystallogr Sect F Struct Biol Cryst Commun 2008; 64:617-21. [PMID: 18607090 DOI: 10.1107/s1744309108015534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 05/23/2008] [Indexed: 11/10/2022]
Abstract
Phototropin is a blue-light receptor protein in plants that is responsible for phototropic responses, stomata opening and photo-induced relocation of chloroplasts. Higher plants such as Arabidopsis thaliana have two isoforms of phototropin: phototropin 1 and phototropin 2. Both isoforms comprise a tandem pair of blue-light-absorbing light-oxygen-voltage domains named LOV1 and LOV2 in the N-terminal half and a serine/threonine kinase domain in the C-terminal half. The LOV1 domain is thought to function as a dimerization site. In the present study, recombinant LOV1 domains of A. thaliana phototropin 1 and phototropin 2 were crystallized. The crystal of the LOV1 domain of phototropin 1 belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 61.2, b = 64.9, c = 70.8 A, and diffracted X-rays to a resolution of 2.1 A. The crystal of the LOV1 domain of phototropin 2 belonged to space group P2(1), with unit-cell parameters a = 32.5, b = 66.5, c = 56.7 A, beta = 92.4 degrees , and diffracted X-rays to beyond 2.0 A resolution. In both crystals, two LOV1 domains occupied the crystallographic asymmetric unit.
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Affiliation(s)
- Masayoshi Nakasako
- Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Kanagawa 223-8522, Japan.
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Abstract
Photoreaction of a blue-light photoreceptor Cryptochrome-DASH (Cry-DASH), a new member of the Cryptochrome family, from zebrafish was studied by UV-visible absorption spectroscopy in aqueous solutions at 293 K. Zebrafish Cry-DASH binds two chromophores, a flavin adenine dinucleotide (FAD) and a N5,N10-methenyl-5,6,7,8-tetrahydrofolate (MTHF) noncovalently. The bound FAD exists in the oxidized form (FAD(ox)) in the dark. Blue light converts FAD(ox) to the neutral radical form (FADH*). Formed FADH* is transformed to the fully reduced form FADH(2) (or FADH(-)) by successive light irradiation, or reverts to FAD(ox). FADH(2) (or FADH(-)) reverts to FADH* or possibly to FAD(ox) directly. The effect of dithiothreitol suggests a possible electron transfer between FAD in zebrafish Cry-DASH and reductants in the external medium. This is the first report on the photoreaction pathway and kinetics of a vertebrate Cry-DASH family protein.
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Affiliation(s)
- Kazunori Zikihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka, Japan
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Ogura Y, Komatsu A, Zikihara K, Nanjo T, Tokutomi S, Wada M, Kiyosue T. Blue light diminishes interaction of PAS/LOV proteins, putative blue light receptors in Arabidopsis thaliana, with their interacting partners. J Plant Res 2008; 121:97-105. [PMID: 17982713 DOI: 10.1007/s10265-007-0118-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 09/13/2007] [Indexed: 05/23/2023]
Abstract
The light, oxygen, or voltage (LOV) domain that belongs to the Per-ARNT-Sim (PAS) domain superfamily is a blue light sensory module. The Arabidopsis thaliana PAS/LOV PROTEIN (PLP) gene encodes three putative blue light receptor proteins, PLPA, PLPB, and PLPC, because of its mRNA splicing variation. PLPA and PLPB each contain one PAS domain at the N-terminal region and one LOV domain at the C-terminal region, while the LOV domain is truncated in PLPC. RNA gel blot analysis showed that PLP mRNA was markedly expressed after exposure to salt or dehydration stress. Yeast two-hybrid screening led to the isolation of VITAMIN C DEFECTIVE 2 (VTC2), VTC2-LIKE (VTC2L), and BEL1-LIKE HOMEODOMAIN 10 proteins (BLH10A and BLH10B) as PLP-interacting proteins. The molecular interaction of PLPA with VTC2L, BLH10A or BLH10B, and that of PLPB with VTC2L were diminished when yeasts were grown under blue light illumination. Furthermore, the possible binding of flavin chromophore to PLPA and PLPB was demonstrated. These results imply that the LOV domain of PLPA and PLPB functions as a blue light sensor, and suggest the applicability of these interactions to blue light-dependent switching in transcriptional regulation in yeast or other organisms.
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Affiliation(s)
- Yasunobu Ogura
- Division of Genome Analysis and Genetic Research, Life Science Research Center, Institute of Research Promotion, Kagawa University, 2393 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0795, Japan
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44
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Yamamoto A, Iwata T, Tokutomi S, Kandori H. Role of Phe1010 in light-induced structural changes of the neo1-LOV2 domain of Adiantum. Biochemistry 2007; 47:922-8. [PMID: 18163650 DOI: 10.1021/bi701851v] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phototropin (phot) is a blue-light sensor protein that elicits several photo responses in plants. Phototropin has two flavin mononucleotide (FMN)-binding domains, LOV1 and LOV2, in its N-terminal half. The C-terminal half is a blue-light-regulated Ser/Thr kinase. Various functional studies have reported that only LOV2 is responsible for the kinase activity, whereas the X-ray crystallographic structures of the LOV1 and LOV2 domains are almost identical. How does such a functional difference emerge? Our previous FTIR study of the LOV domains of Adiantum neochrome1 (neo1) showed that light-induced protein structural changes are small and temperature independent for neo1-LOV1, whereas the structural changes are large and highly temperature dependent for neo1-LOV2, which involve loops, alpha-helices, and beta-sheets. These observations successfully explained the different functions in terms of protein structural changes. They also suggested the presence of some crucial amino acids responsible for greater protein structural changes in the LOV2 domain. Here, we focused on phenylalanine-1010 (Phe1010) in neo1-LOV2, where FMN is sandwiched between Phe1010 and the reactive cysteine. Phenylalanine at this position is conserved for LOV2 domains, while the corresponding amino acid is leucine for LOV1 domains in almost all plant phototropins. We observed that unlike wild-type LOV2, the FTIR spectra of F1010L LOV2 exhibited no temperature dependence in the alpha-helical and beta-sheet regions and that spectral changes in amide-I of these regions were significantly reduced, which was similar to LOV1. Thus, the replacement of phenylalanine with leucine converts neo1-LOV2 into neo1-LOV1 in terms of protein structural changes that must be related to the different functions. We will discuss the roles of phenylalanine and leucine in the LOV2 and LOV1 domains, respectively.
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Affiliation(s)
- Atsushi Yamamoto
- Department of Materials Science and Engineering, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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45
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Tokutomi S, Matsuoka D, Zikihara K. Molecular structure and regulation of phototropin kinase by blue light. Biochim Biophys Acta 2007; 1784:133-42. [PMID: 17988963 DOI: 10.1016/j.bbapap.2007.09.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 08/27/2007] [Accepted: 09/18/2007] [Indexed: 01/15/2023]
Abstract
Phototropin (phot) is a blue light photoreceptor in plants that mediates phototropism, chloroplast movement, stomata opening and leaf expansion. The phot molecule has two photoreceptive domains, LOV 1 and 2, in the N-terminal half and the C-terminal half forms Ser/Thr kinase. Phot acts as a blue light-regulated protein kinase. Each LOV domain binds a FMN and undergoes a unique cyclic reaction upon blue light absorption that induces conformational changes in the protein moiety and leads to regulation of the kinase activity, in which LOV2 plays a predominant role in the switching and LOV1 acts to attenuate the light sensitivity. Phot kinase is classified into the AGC kinase group since the consensus amino acid residues and the motifs are well conserved except for the lack of the hydrophobic motif and the presence of additional amino acid sequence in the activation loop. Secondary structure prediction and 3D structure simulation show a alpha/beta fold of the phot kinase similar to that of the catalytic subunit of PKA. The additional sequence forms an extra helix and loops. Docking simulation of the LOV2 domain with phot kinase provided useful information regarding the molecular mechanism underlying the photoregulation of phot kinase.
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Affiliation(s)
- Satoru Tokutomi
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka, Japan.
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Sato Y, Nabeno M, Iwata T, Tokutomi S, Sakurai M, Kandori H. Heterogeneous environment of the S-H group of Cys966 near the flavin chromophore in the LOV2 domain of Adiantum neochrome1. Biochemistry 2007; 46:10258-65. [PMID: 17705404 DOI: 10.1021/bi701022v] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The primary photochemistry of the blue-light sensor protein, phototropin, is adduct formation between the C4a atom of the flavin mononucleotide (FMN) chromophore and a nearby, reactive cysteine (Cys966), following decay of the triplet excited state of FMN. The distance between the C4a position of FMN and the sulfur atom of Cys966 is 4.2 A in the LOV2 domain of Adiantum neochrome 1 (neo1-LOV2), a fusion protein of phototropin containing the phytochrome chromophoric domain. We previously reported the presence of an unreactive fraction in neo1-LOV2 at low temperatures, which presumably originated from the heterogeneous environment of Cys966 [Iwata, T., Nozaki, D., Tokutomi, S., Kagawa, T., Wada, M., and Kandori, H. (2003) Biochemistry 42, 8183-8191]. The present study showed that (i) 28% forms an adduct at 77 K (state I), (ii) 50% forms an adduct at 150 K but not at 77 K (state II), and (iii) 22% does not form an adduct at 150 K (state III). By Fourier transform infrared (FTIR) spectroscopy, we observed the S-H stretching frequencies at 2570 and 2562 cm-1 for state I and at 2563 cm-1 for state II, suggesting that the microenvironment of the S-H group of Cys966 determines the reactivity at low temperatures. Adduct formation is more efficient for state I than for states II and III. Molecular dynamics simulation strongly suggests that the observed multiple structures originate from the isomeric forms of Cys966. We thus concluded that there are multiple local structures of FMN and cysteine in neo1-LOV2, each of which is thermally converted by protein fluctuation at physiological temperatures.
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Affiliation(s)
- Yoshiaki Sato
- Department of Materials Science and Engineering, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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Eitoku T, Nakasone Y, Zikihara K, Matsuoka D, Tokutomi S, Terazima M. Photochemical Intermediates of Arabidopsis Phototropin 2 LOV Domains Associated with Conformational Changes. J Mol Biol 2007; 371:1290-303. [PMID: 17618649 DOI: 10.1016/j.jmb.2007.06.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 05/26/2007] [Accepted: 06/07/2007] [Indexed: 11/27/2022]
Abstract
The photochemical reactions of Arabidopsis phototropin 2 light- oxygen-voltage domain 2 (LOV2) with the linker region (LOV2-linker), without the linker (LOV2), and LOV1 were studied using the time-resolved transient grating (TG) and transient lens (TrL) methods. Although the absorption spectra did not change after the formation of the adduct species, a small volume expansion process with a time constant of 9 ms was observed for LOV2. For the LOV2-linker, at 293 K, a volume contraction process with a time constant of 140 mus was observed in addition to a volume expansion process with 9 ms and the diffusion coefficient change with 2 ms. The reaction intermediate species were characterized on the basis of their thermodynamic properties, such as changes in enthalpy, thermal expansion, and heat capacity. For the first intermediate (S(390)), the values of these properties were similar to those of the ground state for both LOV2 and LOV2-linker. A relatively large thermal expansion volume (0.09 cm(3)mol(-1)K(-1)) and a positive heat capacity change (4.7 kJ mol(-1)K(-1)) were detected for the intermediates of LOV2-linker. These characteristic features were interpreted in terms of structural fluctuation and exposure of hydrophobic residues in the linker domain, respectively. The enthalpy change of S(390) of the LOV1 domain was significantly greater than changes for the LOV2 or LOV2-linker samples. Data from this study support a major conformational change of the linker region in the photochemical reaction of phototropin.
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Affiliation(s)
- Takeshi Eitoku
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan
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Abstract
Phototropin is a blue-light photoreceptor in plants that mediates phototropism, chloroplast relocation, stomata opening and leaf expansion. Phototropin molecule has two photoreceptive domains named LOV1 (light-oxygen-voltage) and LOV2 in the N-terminus and a serine/threonine kinase domain in the C-terminus, and acts as a blue light-regulated kinase. Each LOV domain binds a flavin mononucleotide as a chromophore and undergoes unique cyclic reactions upon blue-light absorption that comprises a cysteinyl-flavin adduct formation through a triplet-excited state and a successive adduct break to revert to the initial ground state. The molecular reactions underlying the photocycle are reviewed and one of the probable molecular schemes is presented. Adduct formation alters the secondary protein structure of the LOV domains. This structural change could be transferred to the linker between the kinase domain and involved in the photoregulation of the kinase activity. The structural changes as well as the oligomeric structures seem to differ between LOV1 and LOV2, which may explain the proposed roles of each domain in the photoregulation of the kinase activity. The photoregulation mechanism of phototropin kinase is reviewed and discussed in reference to the regulation mechanism of protein kinase A, which it resembles.
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Affiliation(s)
- Daisuke Matsuoka
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Naka-ku, Sakai, Osaka, Japan
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Iwata T, Yamamoto A, Tokutomi S, Kandori H. Hydration and temperature similarly affect light-induced protein structural changes in the chromophoric domain of phototropin. Biochemistry 2007; 46:7016-21. [PMID: 17503781 DOI: 10.1021/bi7003087] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phototropin is a blue-light sensor protein in plants, and LOV domain binds a flavin mononucleotide (FMN) as a chromophore. A photointermediate state, S390, is formed by light-induced adduct formation between FMN and an S-H group of nearby cysteine, which triggers protein structural changes for kinase activation in phototropin. We previously studied the low-temperature Fourier transform infrared (FTIR) spectra between the S390 and unphotolyzed states for a LOV2 domain of a phototropin from Adiantum (neo1-LOV2), and found that the protein structures of the S390 intermediate are highly temperature dependent (Iwata, T., Nozaki, D., Tokutomi, S., Kagawa, T., Wada, M., and Kandori, H. (2003) Biochemistry 42, 8183-8191). At physiological temperature, amide-I vibration at 1640-1620 cm-1 is significantly changed, implying structural alteration of beta-sheet region. Such changes are largely suppressed at low temperatures, though S390 is formed. This observation suggested the presence of progressive protein structural changes in the unique active state (S390). Here we report that the hydration dependence of the amide-I vibrational bands in neo1-LOV2 is similar to the temperature dependence. As hydration of the sample is lowered, amide-I vibration at 1640-1620 cm-1 is significantly reduced. Instead, amide-I vibration at 1694 cm-1 newly emerged at low hydration as well as at low temperature, which shows a weakened hydrogen bond in the loop region. Spectral coincidence between low hydrations and temperatures strongly suggested that protein structural changes are similarly restricted under such conditions. It is likely that protein fluctuations are prerequisite for formation of the active state of neo1-LOV2.
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Affiliation(s)
- Tatsuya Iwata
- Department of Materials Science and Engineering, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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Narikawa R, Zikihara K, Okajima K, Ochiai Y, Katayama M, Shichida Y, Tokutomi S, Ikeuchi M. Three putative photosensory light, oxygen or voltage (LOV) domains with distinct biochemical properties from the filamentous cyanobacterium Anabaena sp. PCC 7120. Photochem Photobiol 2007; 82:1627-33. [PMID: 16922605 DOI: 10.1562/2006-05-02-ra-888] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Light, oxygen or voltage (LOV) domains function as blue-light sensors in the phototropin family of photoreceptors found in plants, algae and bacteria. We detected putative LOV domains (Alr3170-LOV, All2875-LOV and Alr1229-LOV) in the genome of a filamentous cyanobacterium, Anabaena sp. PCC 7120. These cyanobacterial LOV domains are closely clustered with the known LOV domains. Alr3170-LOV and A112875-LOV carry the conserved cysteine residue unique to the photoactive LOV, whereas Alr1229-LOV does not. We expressed these three LOV domains in Escherichia coli and purified them. In fact, Alr3170-LOV and A112875-LOV that are conserved in Nostoc punctiforme, a related species, bound flavin mononucleotide and showed spectral changes unique to known LOV domains on illumination with blue light. Alr3170-LOV was completely photoreduced and dark reversion was slow, whereas A112875-LOV was slowly photoreduced and dark reversion was rapid. For comparison, AvA112875-LOV in a closely related A. variabilis was also studied as a homolog of A112875-LOV. Finally, we observed that Alr1229-LOV that is not conserved in N. punctiforme showed no flavin binding.
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Affiliation(s)
- Rei Narikawa
- Department of Life Sciences (Biology), Graduate School of Art and Sciences, University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan
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