@article{2fb2a11f463a4faea0ad8e704eb8b630,
title = "Molecular shape under far-red light and red light-induced association of Arabidopsis phytochrome B",
abstract = "Phytochrome B (phyB) is a plant photoreceptor protein that regulates various photomorphogenic responses to optimize plant growth and development. PhyB exists in two photoconvertible forms: a red light-absorbing (Pr) and a far-red light-absorbing (Pfr) form. Therefore, to understand the mechanism of phototransformation, the structural characterization of full-length phyB in these two forms is necessary. Here, we report the molecular structure of Arabidopsis thaliana phyB in Pr form and the molecular properties of the Pfr form determined by small-angle X-ray scattering coupled with size-exclusion chromatography. In solution, the Pr form associated as a dimer with a radius of gyration of 50 {\AA}. The molecular shape was a crossed shape, in which the orientation of the photosensory modules differed from that in the crystal structure of dimeric photosensory module. PhyB exhibited structural reversibility in the Pfr-to-Pr phototransformation and thermal reversion from Pfr to Pr in the dark. In addition, Pfr only exhibited nonspecific association, which distinguished molecular properties of Pfr form from those of the inactive Pr form.",
keywords = "light-induced changes, molecular shape, phytochrome B, size-exclusion chromatography, small-angle X-ray scattering",
author = "Mao Oide and Takaaki Hikima and Tomotaka Oroguchi and Takayuki Kato and Yuhki Yamaguchi and Shizue Yoshihara and Masaki Yamamoto and Masayoshi Nakasako and Koji Okajima",
note = "Funding Information: The authors thank Dr Takatoshi Kagawa of National Institute for Agro‐Environmental Sciences for his kind provision of the vector of chromophore synthesis and also Professor Keiichi Namba of Osaka University for the use of an EM facility. This research was partly supported by Grants‐in‐Aid for Scientific Research from the Japan Society for the Promotion of Science to MN (Nos. jp1920402 and jp22244054), to T.O. (Nos. jp17K19209 and jp17H04854), to K.O. (No. jp15K18559), and to M.O. (No. 18J11653 for JSPS Fellows), as well as by grants from the Ministry of Education, Culture, Sports, Science and Technology, Japan, to MN (Nos. jp15076210, jp20050030, jp22018027, jp23120525, jp25120725, jp15H01647, and jp17H05891) and to T.O. (Nos. jp24113723 and jp26104535). SAXS experiments were performed at BL45XU with the approval of the RIKEN Harima Institute (proposal No. 20180071) and were partially supported by the Platform Project for Supporting Drug Discovery and Life Science Research (Basis for Supporting Innovative Drug Discovery and Life Science Research (BINDS)) from the Japan Agency for Medical Research and Development (project No. 0437). ",
year = "2020",
month = apr,
day = "1",
doi = "10.1111/febs.15095",
language = "English",
volume = "287",
pages = "1612--1625",
journal = "FEBS Journal",
issn = "1742-464X",
publisher = "Wiley-Blackwell",
number = "8",
}