Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2

Yuki Takayama, Masayoshi Nakasako, Koji Okajima, Aya Iwata, Sachiko Kashojiya, Yuka Matsui, Satoru Tokutomi

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Phototropin, a blue-light receptor protein of plants, triggers phototropic responses, chloroplast relocation, and opening of stomata to maximize the efficiency of photosynthesis. Phototropin is composed of two light-oxygen-voltage sensing domains (LOV1 and LOV2) that absorb blue light and a serine/theroine kinase domain responsible for light-dependent autophosphorylation leading to cellular signaling cascades. Although the light-activated LOV2 domain is primarily responsible for subsequent activation of the kinase domain, it is unclear how conformational changes in the former transmit to the latter. To understand this molecular mechanism in Arabidopsis phototropin 2, we performed small-angle X-ray scattering analysis on a fragment composed of the LOV2 and kinase domains, which contained an Asp720Asn mutation that led to an absence of ATP binding activity. The scattering data were collected up to a resolution of 25 Å. The apparent molecular weight of the fragment estimated from scattering intensities demonstrated that the fragment existed in a monomeric form in solution. The fragment exhibited photoreversible changes in the scattering profiles, and the radii of gyration under dark and blue-light irradiation conditions were 32.4 and 34.8 Å, respectively. In the dark, the molecular shape restored from the scattering profile appeared as an elongated shape of 110 Å in length and 45 Å in width. The homology modeled LOV2 and kinase domains could be fitted to the molecular shape and appeared to make slight contact. However, under blue-light irradiation, a more extended molecular shape was observed. The changes in the molecular shape and radius of gyration were interpreted as a light-dependent positional shift of the LOV2 domain of approximately 13 Å from the kinase domain. Because the region connecting the LOV2 and kinase domains was categorized as a naturally unfolded polypeptide, we propose that the light-activated LOV2 domain triggers conformational changes in the linker region to separate the LOV2 and kinase domains.

Original languageEnglish
Pages (from-to)1174-1183
Number of pages10
JournalBiochemistry
Volume50
Issue number7
DOIs
Publication statusPublished - 2011 Feb 22

Fingerprint

Phototropins
Arabidopsis
Phosphotransferases
Light
Scattering
Irradiation
Cell signaling
Plant Proteins
Relocation
Photosynthesis
Protein-Serine-Threonine Kinases
Chloroplasts
X ray scattering
Adenosine Triphosphate
Molecular Weight
Chemical activation
Molecular weight

ASJC Scopus subject areas

  • Biochemistry

Cite this

Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2. / Takayama, Yuki; Nakasako, Masayoshi; Okajima, Koji; Iwata, Aya; Kashojiya, Sachiko; Matsui, Yuka; Tokutomi, Satoru.

In: Biochemistry, Vol. 50, No. 7, 22.02.2011, p. 1174-1183.

Research output: Contribution to journalArticle

Takayama, Y, Nakasako, M, Okajima, K, Iwata, A, Kashojiya, S, Matsui, Y & Tokutomi, S 2011, 'Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2', Biochemistry, vol. 50, no. 7, pp. 1174-1183. https://doi.org/10.1021/bi101689b
Takayama, Yuki ; Nakasako, Masayoshi ; Okajima, Koji ; Iwata, Aya ; Kashojiya, Sachiko ; Matsui, Yuka ; Tokutomi, Satoru. / Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2. In: Biochemistry. 2011 ; Vol. 50, No. 7. pp. 1174-1183.
@article{870dbe369ae44f5990482d961224c483,
title = "Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2",
abstract = "Phototropin, a blue-light receptor protein of plants, triggers phototropic responses, chloroplast relocation, and opening of stomata to maximize the efficiency of photosynthesis. Phototropin is composed of two light-oxygen-voltage sensing domains (LOV1 and LOV2) that absorb blue light and a serine/theroine kinase domain responsible for light-dependent autophosphorylation leading to cellular signaling cascades. Although the light-activated LOV2 domain is primarily responsible for subsequent activation of the kinase domain, it is unclear how conformational changes in the former transmit to the latter. To understand this molecular mechanism in Arabidopsis phototropin 2, we performed small-angle X-ray scattering analysis on a fragment composed of the LOV2 and kinase domains, which contained an Asp720Asn mutation that led to an absence of ATP binding activity. The scattering data were collected up to a resolution of 25 {\AA}. The apparent molecular weight of the fragment estimated from scattering intensities demonstrated that the fragment existed in a monomeric form in solution. The fragment exhibited photoreversible changes in the scattering profiles, and the radii of gyration under dark and blue-light irradiation conditions were 32.4 and 34.8 {\AA}, respectively. In the dark, the molecular shape restored from the scattering profile appeared as an elongated shape of 110 {\AA} in length and 45 {\AA} in width. The homology modeled LOV2 and kinase domains could be fitted to the molecular shape and appeared to make slight contact. However, under blue-light irradiation, a more extended molecular shape was observed. The changes in the molecular shape and radius of gyration were interpreted as a light-dependent positional shift of the LOV2 domain of approximately 13 {\AA} from the kinase domain. Because the region connecting the LOV2 and kinase domains was categorized as a naturally unfolded polypeptide, we propose that the light-activated LOV2 domain triggers conformational changes in the linker region to separate the LOV2 and kinase domains.",
author = "Yuki Takayama and Masayoshi Nakasako and Koji Okajima and Aya Iwata and Sachiko Kashojiya and Yuka Matsui and Satoru Tokutomi",
year = "2011",
month = "2",
day = "22",
doi = "10.1021/bi101689b",
language = "English",
volume = "50",
pages = "1174--1183",
journal = "Biochemistry",
issn = "0006-2960",
publisher = "American Chemical Society",
number = "7",

}

TY - JOUR

T1 - Light-induced movement of the LOV2 domain in an Asp720Asn mutant LOV2-kinase fragment of arabidopsis phototropin 2

AU - Takayama, Yuki

AU - Nakasako, Masayoshi

AU - Okajima, Koji

AU - Iwata, Aya

AU - Kashojiya, Sachiko

AU - Matsui, Yuka

AU - Tokutomi, Satoru

PY - 2011/2/22

Y1 - 2011/2/22

N2 - Phototropin, a blue-light receptor protein of plants, triggers phototropic responses, chloroplast relocation, and opening of stomata to maximize the efficiency of photosynthesis. Phototropin is composed of two light-oxygen-voltage sensing domains (LOV1 and LOV2) that absorb blue light and a serine/theroine kinase domain responsible for light-dependent autophosphorylation leading to cellular signaling cascades. Although the light-activated LOV2 domain is primarily responsible for subsequent activation of the kinase domain, it is unclear how conformational changes in the former transmit to the latter. To understand this molecular mechanism in Arabidopsis phototropin 2, we performed small-angle X-ray scattering analysis on a fragment composed of the LOV2 and kinase domains, which contained an Asp720Asn mutation that led to an absence of ATP binding activity. The scattering data were collected up to a resolution of 25 Å. The apparent molecular weight of the fragment estimated from scattering intensities demonstrated that the fragment existed in a monomeric form in solution. The fragment exhibited photoreversible changes in the scattering profiles, and the radii of gyration under dark and blue-light irradiation conditions were 32.4 and 34.8 Å, respectively. In the dark, the molecular shape restored from the scattering profile appeared as an elongated shape of 110 Å in length and 45 Å in width. The homology modeled LOV2 and kinase domains could be fitted to the molecular shape and appeared to make slight contact. However, under blue-light irradiation, a more extended molecular shape was observed. The changes in the molecular shape and radius of gyration were interpreted as a light-dependent positional shift of the LOV2 domain of approximately 13 Å from the kinase domain. Because the region connecting the LOV2 and kinase domains was categorized as a naturally unfolded polypeptide, we propose that the light-activated LOV2 domain triggers conformational changes in the linker region to separate the LOV2 and kinase domains.

AB - Phototropin, a blue-light receptor protein of plants, triggers phototropic responses, chloroplast relocation, and opening of stomata to maximize the efficiency of photosynthesis. Phototropin is composed of two light-oxygen-voltage sensing domains (LOV1 and LOV2) that absorb blue light and a serine/theroine kinase domain responsible for light-dependent autophosphorylation leading to cellular signaling cascades. Although the light-activated LOV2 domain is primarily responsible for subsequent activation of the kinase domain, it is unclear how conformational changes in the former transmit to the latter. To understand this molecular mechanism in Arabidopsis phototropin 2, we performed small-angle X-ray scattering analysis on a fragment composed of the LOV2 and kinase domains, which contained an Asp720Asn mutation that led to an absence of ATP binding activity. The scattering data were collected up to a resolution of 25 Å. The apparent molecular weight of the fragment estimated from scattering intensities demonstrated that the fragment existed in a monomeric form in solution. The fragment exhibited photoreversible changes in the scattering profiles, and the radii of gyration under dark and blue-light irradiation conditions were 32.4 and 34.8 Å, respectively. In the dark, the molecular shape restored from the scattering profile appeared as an elongated shape of 110 Å in length and 45 Å in width. The homology modeled LOV2 and kinase domains could be fitted to the molecular shape and appeared to make slight contact. However, under blue-light irradiation, a more extended molecular shape was observed. The changes in the molecular shape and radius of gyration were interpreted as a light-dependent positional shift of the LOV2 domain of approximately 13 Å from the kinase domain. Because the region connecting the LOV2 and kinase domains was categorized as a naturally unfolded polypeptide, we propose that the light-activated LOV2 domain triggers conformational changes in the linker region to separate the LOV2 and kinase domains.

UR - http://www.scopus.com/inward/record.url?scp=79951619904&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79951619904&partnerID=8YFLogxK

U2 - 10.1021/bi101689b

DO - 10.1021/bi101689b

M3 - Article

C2 - 21222437

AN - SCOPUS:79951619904

VL - 50

SP - 1174

EP - 1183

JO - Biochemistry

JF - Biochemistry

SN - 0006-2960

IS - 7

ER -