Staff

ARAI TatsuyaAssistant Professor

Laboratory
Laboratory of Protein Science
Research Theme
Structural and functional analysis of antifreeze protein, Measurement of dynamics using time-resolved X-ray diffrraction
Research Keywords

protein science, structural biology, X-ray crystallography, antifreeze protein, ice-crystal, cryo-biology, phylogenetics, time-resolved X-ray diffraction, polymer nanocomposite, molecular dynamics

Overview of Research

(1) Structural, Functional, and Phylogenetic Analysis of Antifreeze Proteins (AFPs)

Why don’t fish living in the Arctic or Antarctic seas freeze? Over 50 years ago, researchers discovered the answer to this question, which are Antifreeze Proteins (AFPs). AFPs are found in high concentrations in the bodily fluids of organisms inhabiting low-temperature environments. It is believed that AFPs inhibit the growth of ice crystals by binding to them, thereby preventing the freezing of the entire body. AFPs of various structures have been discovered not only in polar fish but also in insects like stag beetles, plants like carrots, and microorganisms like fungi. I am studying how these diverse AFP molecules: (i) bind to ice, (ii) have evolved, and (iii) can be applied. These studies significantly contribute to the advancement of technologies such as cryopreservation of food and biological materials.

(2) Dynamics measurement of polymer nanocomposite materials using time-resolved X-ray diffraction

Polymer nanocomposites (PNCs) are composite materials where nanoparticles are mixed with polymers, widely used in various products and materials such as rubber, gels, resin materials, and adhesives. In PNCs, nano-level interactions between polymers and nanoparticles are known to govern macroscopic properties such as tensile strength and hardiness. I am studying such interactions from the perspective of dynamics, aiming to understand their relationship with macroscopic properties. Particularly, I am developing and applying a method called Diffracted X-ray Blinking (DXB) to measure dynamics from time-resolved X-ray diffraction images of PNCs.

Charge

Message

Many researchers are fascinated by the diverse structures and functions of proteins. Would you like to join us in discovering, analyzing, and advancing new proteins together?

Representative Publications

T. Arai, K. Mio, H. Onoda, L.M.G. Chavas, Y. Umena, Y.C. Sasaki, The Blinking of Small-Angle X-ray Scattering Reveals the Degradation Process of Protein Crystals at Microsecond Timescale, Int J Mol Sci. 24 (2023) 16640.

Y. Yang, A. Yamauchi, S. Tsuda, M. Kuramochi, K. Mio, Y.C. Sasaki, T. Arai, The ice-binding site of antifreeze protein irreversibly binds to cell surface for its hypothermic protective function, Biochem Biophys Res Commun. 682 (2023) 343–348.

T. Arai, A. Yamauchi, Y. Yang, S.M. Singh, Y.C. Sasaki, S. Tsuda, Adsorption of ice-binding proteins onto whole ice crystal surfaces does not necessarily confer a high thermal hysteresis activity, Sci Rep. 12 (2022) 15443.

T. Arai, R. Inamasu, H. Yamaguchi, D. Sasaki, A. Sato-Tomita, H. Sekiguchi, K. Mio, S. Tsuda, M. Kuramochi, Y.C. Sasaki, Laboratory diffracted x-ray blinking to monitor picometer motions of protein molecules and application to crystalline materials, Structural Dynamics. 8 (2021) 044302.

T. Arai, A. Yamauchi, A. Miura, H. Kondo, Y. Nishimiya, Y.C. Sasaki, S. Tsuda, Discovery of Hyperactive Antifreeze Protein from Phylogenetically Distant Beetles Questions Its Evolutionary Origin, Int J Mol Sci. 22 (2021) 3637.

T. Arai, Y. Nishimiya, Y. Ohyama, H. Kondo, S. Tsuda, Calcium-binding generates the semi-clathrate waters on a type II antifreeze protein to adsorb onto an ice crystal surface, Biomolecules. 9 (2019).

T. Arai, D. Fukami, T. Hoshino, H. Kondo, S. Tsuda, Ice-binding proteins from the fungus Antarctomyces psychrotrophicus possibly originate from two different bacteria through horizontal gene transfer, FEBS Journal. 286 (2019) 946–962.

Note

<Office Hour>
– Time: Anytime during the lecture period
– Place: Science Bldg. No.2, 7F, #2-710
Please contact in advance by E-mail.
E-mail: t.arai[at]elms.hokudai.ac.jp

Affiliation