Presentations -

Paip2による翻訳抑制機構の構造生物学的解析

寒河江 彪流, 横川 真梨子, 沢崎 綾一, 細田 直, 星野 真一, 大澤 匡範

[Domestic presentation]  第61回 日本薬学会 関東支部大会, 

2017.09

, 

Poster presentation

ポリA 上のPABP 多量体による翻訳調節メカニズムの解明

沢崎綾一, 今井駿輔, 横川真梨子, 細田直, 星野真一, 三尾宗代, 三尾 和弘, 嶋田一夫, 大澤匡範

[Domestic presentation]  第1回　慶應ライフサイエンスシンポジウム, 

2017.08

, 

Poster presentation

Gタンパク質のファミリー選択的なK+チャネル活性制御機構の解明

加納 花穂, 外山 侑樹, 岩橋 優太, 間瀬 瑶子, 横川 真梨子, 大澤 匡範, 嶋田 一夫

[Domestic presentation]  第17回日本蛋白質科学会年会 (仙台国際センター（宮城県仙台市）) , 

2017.06

, 

Poster presentation

カリウムチャネルのミリ秒オーダーの開閉の構造機構の解明

岩橋 優太, 外山 侑樹, 今井 駿輔, 大澤 匡範, 嶋田 一夫

第17回日本蛋白質科学会年会 (仙台国際センター（宮城県仙台市）) , 

2017.06

, 

Poster presentation

Structural mechanism of functional regulation of the voltage-gated ion channels by ligand binding to voltage-sensing domain.

大澤匡範

[International presentation]  The 94th Annual Meeting of the Physiological Society of Japan (アクトシティ浜松（静岡県浜松市）) , 

2017.03

, 

Oral presentation (invited, special)

Structural mechanism underlying the millisecond gating of K+ channel.

Yuta Iwahashi, Yuki Toyama, Shunsuke Imai, Masanori Osawa, Ichio Shimada.

[International presentation]  58th Experimental Nuclear Magnetic Resonance Conference (Asilomar Conference Center, Pacific Grove, California) , 

2017.03

, 

Poster presentation

　View Summary

KcsA is a pH-dependent K+ channel, which opens under acidic conditions. Under the acidic conditions, KcsA switches between open and closed states on a millisecond timescale (msec-gating), which regulates the K+ permeation in cells. However, the structural mechanism of the msec-gating has remained unclear. In this research, we designed KcsA mutants with different open probabilities in the msec-gating, and conducted NMR experiments on these mutants. We revealed that KcsA undergoes an equilibrium between two conformations, which differ in structures of a cytoplasmic transmembrane gate, and the ratios of these conformations well correlate with the open probabilities in the msec-gating. From these results, we conclude that the conformational equilibrium in the cytoplasmic transmembrane gate leads to the msec-gating.

Dynamic regulation of GDP binding to G proteins revealed by magnetic field-dependent NMR relaxation analyses.

Yuki Toyama, Hanaho Kano, Yoko Mase, Mariko Yokogawa, Masanori Osawa, Ichio Shimada.

[International presentation]  58th Experimental Nuclear Magnetic Resonance Conference (Asilomar Conference Center, Pacific Grove, California) , 

2017.03

, 

Poster presentation

　View Summary

Heterotrimeric guanine-nucleotide binding proteins (G proteins) serve as molecular switches in signaling pathways, by coupling the activation of cell surface receptors to intracellular responses. Mutations in the G protein alpha subunit (Gα) that accelerate GDP dissociation cause hyperactivation of the downstream effector proteins, leading to oncogenesis. However, the structural mechanism of the accelerated GDP dissociation has remained unclear. Here, we use magnetic field-dependent relaxation analyses to investigate the structural and dynamic properties of Gα. We show that Gα rapidly exchanges between a ground state conformation, which tightly binds to GDP and an excited conformation with reduced GDP affinity. The oncogenic D150N mutation accelerates GDP dissociation by shifting the equilibrium towards the excited conformation.

Molecular mechanism of the ATP-dependent modulation of the Mg2+ channel MgtE for Mg2+ homeositasis.

Atsuhiro Tomita, Mingfeng Zhang, Hironori Takeda, Fei Jin, Tatsuro Maruyama, Masanori Osawa, Ryuichiro Ishitani, Ichio Shimada, Zhiqiang Yan, Motoyuki Hattori, Osamu Nureki.

[Domestic presentation]  The 54th Annual Meeting of the Biophysical Society of Japan, 

2016.11

, 

Poster presentation

Developments and applications of multiple quantum NMR methods to characterize functional dynamics of high molecular weight proteins.

Yuki Toyama, Hanaho Kano, Yoko Mase, Mariko Yokogawa, Masanori Osawa, Ichio Shimada.

[Domestic presentation]  The 54th Annual Meeting of the Biophysical Society of Japan, 

2016.11

, 

Oral presentation (invited, special)

Structural basis for the inhibition of voltage-dependent K+ channel by gating modifier toxin.

Osawa M.

[International presentation]  The 42nd Naito Conference, 

2016.10

, 

Oral presentation (invited, special)

Gating modifier toxinによる電位依存性K+チャネル阻害の構造基盤

大澤匡範

[Domestic presentation]  第60回日本薬学会関東支部大会 (東京) , 

2016.09

, 

Oral presentation (invited, special), 日本薬学会関東支部

Structural Basis for the Inhibition of Voltage-dependent K+ Channel by Gating Modifier Toxin.

Osawa M.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological System, 

2016.08

, 

Poster presentation

NMR Method for Characterizing Microsecond-to-Millisecond Chemical Exchanges Utilizing Differential Multiple-Quantum Relaxation in High Molecular Weight Proteins.

Yuki Toyama, Masanori Osawa, Mariko Yokogawa, Ichio Shimada.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological Systems, 

2016.08

, 

Poster presentation

Structural Basis for Voltage-Sensing Mechanism of a Voltage-Dependent Potassium Channel.

Tomohiro Nozaki, Shin-ichiro Ozawa, Hitomi Harada, Tomomi Kimura, Masanori Osawa, Ichio Shimada.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological Systems, 

2016.08

, 

Poster presentation

Structural Basis for the Inhibition of Voltage-dependent K+ Channel by Gating Modifier Toxin.

Osawa M.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological Systems., 

2016.08

, 

Oral presentation (general)

Structural Characterization of PABP Multimerization on Poly(A) Tail.

Ryoichi Sawazaki, Shunsuke Imai, Mariko Yokogawa, Yoko Usui1, Takeru Sagae, Shin-ichi Hoshino, Ichio Shimada, Masanori Osawa.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological Systems, 

2016.08

, 

Poster presentation

Functional Roles of Mg2+-Binding Sites in Mg2+-Dependent Gating of an Mg2+ Channel, MgtE, Revealed by NMR.

Tatsuro Maruyama, Shunsuke Imai, Motoyuki Hattori, Ryuichiro Ishitani, Osamu Nureki,Ichio Shimada, Masanori Osawa.

[International presentation]  The 27th International Conference on Magnetic Resonance in Biological Systems, 

2016.08

, 

Poster presentation

Structural Basis for the Inhibition of Voltage-dependent K+ Channel by Gating Modifier Toxin.

Osawa M.

[International presentation]  International and Interdisciplinary Symposium 2016 "Towards a New Era of Cardiovascular Research, 

2016.07

, 

Poster presentation

NMR Method for Characterizing Microsecond-to-Millisecond Chemical Exchanges Utilizing Differential Multiple-Quantum Relaxation in High Molecular Weight Proteins.

Toyama Y., Osawa M, .Yokogawa M., Shimada I.

[Domestic presentation]  第16回東京大学生命科学シンポジウム, 

2016.04

, 

Poster presentation

Structural basis for the inhibition of voltage-dependent K+ channel by gating modifier toxin.

Shin-ichiro Ozawa, Tomomi Kimura, Tomohiro Nozaki, Hitomi Harada, Ichio Shimada, Masanori Osawa.

[Domestic presentation]  日本薬学会物理系薬学部会シンポジウム (横浜) , 

2016.03

, 

Oral presentation (invited, special), 日本薬学会物理系薬学部会