Magnetic excitations in the orbital disordered phase of MnVO

Matsuura, Keisuke*; Sagayama, Hajime*; Uehara, Amane*; Nii, Yoichi*; Kajimoto, Ryoichi; Kamazawa, Kazuya*; Ikeuchi, Kazuhiko*; Ji, S.*; Abe, Nobuyuki*; Arima, Takahisa*

Physica B; Condensed Matter, 536, p.372 - 376, 2018/05

https://doi.org/10.1016/j.physb.2017.09.085

Distinct structural requirements for interleukin-4 (IL-4) and IL-13 binding to the shared IL-13 receptor facilitate cellular tuning of cytokine responsiveness

Ito, Takachika*; Suzuki, Shoichi*; Kanaji, Sachiko*; Shiraishi, Hiroshi*; Ota, Shoichiro*; Arima, Kazuhiko*; Tanaka, Go*; Tamada, Taro; Honjo, Eijiro*; Garcia, K. C.*; et al.

Journal of Biological Chemistry, 284(36), p.24289 - 24296, 2009/09

https://doi.org/10.1074/jbc.M109.007286

Both IL-4 and IL-13 can bind to the shared receptor composed of the IL-4 receptor chain and the IL-13 receptor -1 chain (IL-13R1); however, the assembly mechanisms of these ligands to the receptor is different, enabling the principal functions of these ligands to be different. We have previously shown that the N-terminal Ig-like domain in IL-13R1, called the D1 domain, is the specific and critical binding unit for IL-13. However, it has still remained obscure which the amino acid has specific binding capacity to IL-13 and why the D1 domain acts as the binding site for IL-13, but not IL-4. To address these questions, in this study, we performed the mutational analyses for the D1 domain, combining the structural data to identify the amino acids critical for binding to IL-13. Mutations of Lys76, Lys77, or Ile78 in c' strand in which the crystal structure showed interact with IL-13 and those of Trp65 and Ala79 adjacent to the interacting site, resulted in significant impairment of IL-13 binding, demonstrating that these amino acids generate the binding site. Furthermore, mutations of Val35, Leu38, or Val42 at N-terminal -strand also resulted in loss of IL-13 binding, probably from decrease structural stability. None of the mutations employed here affected IL-4 binding. These results demonstrate that the hydrophobic patch composed of Lys76, Lys77, and Ile78 is the IL-13 recognition site and solidify our understanding that the differential requirements of the D1 domain in IL-13R1 allows the shared receptor to respond differentially to IL-4 and IL-13.

Expression and purification of extracellular region of interleukin-13 receptor 1 chain and its interaction with its ligand

Kuroki, Ryota; Honjo, Eijiro; Tamada, Taro; Arima, Kazuhiko*; Izuhara, Kenji*

no journal, , 

Interleukin-13 (IL-13) interacts with two types of receptors, the IL-13R1 chain (IL-13R1) and the IL-4R chain (IL-4R), that transduce the IL-13 signals. In order to investigate the interaction of IL-13 with IL-13R1 and IL-4R, the genes coding the extracellular regions of human IL-13R1 and the IL-4R containing cytokine receptor homologous region (CRH), were fused with human Fc, and expressed by silk worm. After further purification with anion-exchange chromatography, the receptors were used to investigate the ligand-receptor interaction. The size exclusion chromatography showed that association between IL-13 and IL-13Ra1 could not be observed in this condition whereas the clear association of IL-13 and IL-13Ra1 was observed after adding IL-4R. It indicates that the association between IL-13 and IL-4R increase the IL-13 affinity to IL-13R1.

Current status of the new polarized neutron reflectometer (SHARAKU) at J-PARC, and prospects for study on multilayers

Kubota, Masato; Takeda, Masayasu; Yamazaki, Dai; Hayashida, Hirotoshi; Maruyama, Ryuji; Soyama, Kazuhiko; Asaoka, Hidehito; Yamazaki, Tatsuya; Sakasai, Kaoru; To, Kentaro; et al.

no journal, , 

no abstracts in English

Constructing autonomous distributed infrastructure systems; Super energy saving ecosystems using power electronics based on widegap semiconductors

Ito, Hisayoshi; Oshima, Takeshi; Okumura, Hajime*; Harima, Hiroshi*; Kishida, Shunji*; Hiramoto, Toshiro*; Hirakawa, Kazuhiko*

no journal, , 

In the presentation, we propose the construction of the super energy saving ecosystems using power electronics based on widegap semiconductors, as autonomous distributed infrastructure systems which work even in emergency cases like East Japan great earthquake disaster. This proposal consists of (1) R&D of advanced power electronics using widegap semiconductors like silicon carbide (SiC) and (2) the construction of super low loss energy control and communication systems based on such advanced power electronics. By realizing such super energy saving ecosystems, advanced eco-cities resisting a disaster are expected to be built. The proposed ecosystems are also quite effective for preventing global warming and promoting industrial development.