Hierarchical Functional Construction of Cellular Motile Systems

细胞运动系统的分层功能构建

基本信息

批准号：
19207011
负责人：
ISHIWATA Shin'ichi
金额：
$ 33.36万
依托单位：
Waseda University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2007
资助国家：
日本
起止时间：
2007 至 2009
项目状态：
已结题

项目摘要

We focused on the examination of the effect of force on the activity of the molecular motors in a wide range of the hierarchical organization of the biological systems, from single molecules to assemblies of the motors and further on to the cells. Main achievements are summarized as follows : 1) The external forces were applied at various angles to the individual molecules of myosin V, processively moving on actin filaments in the presence of ATP, to test the robustness of the motor's motility under various loads. Furthermore, the mechanism ensuring high stability of the myosin V's motility under external loads was revealed by applying loads in various directions and measuring the unbinding forces of individual actin-myosin V complexes at different [ADP] (Oguchi et al., Nature Chem. Biol., 2010 ; for myosin VI, see Oguchi et al., PNAS, 2008). The main results of the unbinding force measurements on different motors, including myosins V and VI, as well as myosin II and kinesin, were summ … More arized and published (Mikhailenko et al., J. Royal Soc. Interface, 2010). 2) The response of individual sarcomeres in a single myofibril to the external mechanical stimulation under intermediate activation conditions revealed the coexistence of two types of sarcomeres : those responding to the application of load, and those remaining indifferent. These observations confirmed the existence of a mechanical inter-sarcomere coordination, helping us to establish the characteristic mechanism of muscle contraction and regulation (Shimamoto et el., PNAS, 2009). 3) We constructed the theoretic model explicitly describing the characteristics of contraction, including the auto-oscillation (SPOC), in a striated muscle (Sato et al., 2010, submitted). 4) We published the first report based on our research on vertebrate meiotic spindles self-assembled in Xenopus egg extracts, in which we tested their mechanical properties, such as deformability and stiffness, and the response to mechanical perturbations (Itabashi et al., Nature Methods, 2009). This work reported, inter alia, that the spontaneous re-assembly of spindles of different sizes can be induced by applying large controlled external loads. 5) To reveal the mechanisms underlying the stability of a characteristic "rugby ball"-like shape of the meiotic spindle, we quantitatively tested its response to mechanical stretch along the polar (long) axis, produced by the micromanipulation with a pair of microneedles. These measurements clearly demonstrated that a spindle responds to the large externally induced deformations, being able to preserve its shape via the modulation of polymerization/depolymerization of microtubules and the activity of kinesin and dynein molecular motors (MS in preparation). 6) We found that the local heating of HeLa cells using the ≧1 sec heat pulses, which increase the local temperature within cells by 0.1～few degrees centigrade, induces the oscillation of intracellular [Ca^<2+>]. Moreover, around 37℃ the cell responds to small, ～0.2℃, temperature changes, in which the IP_3 receptors were shown to be involved (Suzuki et al., HFSP J., 2009). Less

我们专注于研究力对生物系统分层组织中分子电机活性的影响，从单分子到电动机的组件再到细胞。主要成就总结如下：1）外部力以各个角度与肌球蛋白V的各个分子施加，在ATP存在下在肌动蛋白丝上进行了过程，以测试各种负载下电动机运动的稳健性。此外，通过在不同的方向上施加载荷并测量不同[ADP]的单个肌动蛋白膜V复合物的解开力来确保肌球蛋白V在外部载荷下的高稳定性（Oguchi等人，自然化学疗法，自然化学，2010; myososin vi，for Myosin vi vi，oguchi et oguchi等人，pnas et al。）总结了包括肌动蛋白V和VI以及肌球蛋白II和动力蛋白在内的不同电动机上的无限力测量的主要结果。 2）在中间激活条件下，单个肌原纤维中各个肉瘤对外部机械刺激的响应揭示了两种类型的肉瘤的共存：响应负载的施加的肉瘤，而那些却保持无关。这些观察结果证实了机械触发间协调的存在，有助于我们建立肌肉收缩和调节的特征机制（Shimamoto等，PNAS，PNAS，2009）。 3）我们构建了理论模型，明确描述了收缩的特征，包括自动振荡（SPOC），在条纹的肌肉中（Sato等人，2010年，提交）。 4）我们根据对静脉卵提取物中脊椎动物减数分裂的研究的研究发表了第一份报告，其中我们测试了它们的机械性能，例如变形和刚度，以及对机械扰动的响应（Itabashi等人，自然方法，2009年）。除此之外，这项工作报告说，可以通过施加大型受控外部载荷来诱发不同尺寸的纺锤体的赞助商组装。 5）揭示了特征性“橄榄球”形状的稳定性的机制，我们定量测试了其沿极（长）轴的机械拉伸的响应，该轴是由微观渗透与一对微针产生的。这些测量值清楚地表明，对大型外部诱导的变形的主轴响应能够通过调节微管的聚合/解聚化以及驱动蛋白和动力蛋白分子电动机的活性（制备中的MS）。 6）我们发现，使用≧1秒的热脉冲对HeLa细胞的局部加热，从而将细胞内的局部温度提高了0.1至几摄氏度，从而诱导细胞内[Ca^<2+>]的振荡。此外，大约37℃对小的细胞反应，〜0.2℃，温度变化，其中IP_3受体被证明涉及（Suzuki等人，HFSP J.，2009）。较少的

项目成果

期刊论文数量（101）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

ミオシンVのコンバータードメインにある疎水残基は分子内の方の伝達において重要である

肌球蛋白 V 转换器结构域中的疏水残基对于分子内通讯很重要

DOI：
发表时间：
2008
期刊：
影响因子：
0
作者：
吉本順一;他5名
通讯作者：
他5名

心筋の自励振動能 : アクチン・ミオシンモーター蛋白質の働き他22件

心肌自激振荡能力：肌动蛋白/肌球蛋白运动蛋白等22种的功能

DOI：
发表时间：
2008
期刊：
影响因子：
0
作者：
Satoshi Kimura;Yoshiho Ikeuchi;Tomoyuki Numata;Daigo Nakamura;Takashi Yokogawa;Kazuya Nishikawa;Takeshi Wada;Takeo Suzuki;Tsutomu Suzuki;石渡信一
通讯作者：
石渡信一

活性化レベルに依存する骨格筋自励振動現象の振舞い

骨骼肌自激振动现象的行为取决于激活水平