...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Interaction of profilin with the barbed end of actin filaments
【24h】

Interaction of profilin with the barbed end of actin filaments

机译：Profilin与肌动蛋白丝的刺末端的相互作用

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Profilin binds not only to actin monomers but also to the barbed end of the actin filament, where it inhibits association of subunits. To address open questions about the interactions of profilin with barbed ends, we measured the effects of a wide range of concentrations of Homo sapiens profilin 1 on the rate of elongation of individual skeletal muscle actin filaments by total internal reflection fluorescence microscopy. Much higher concentrations of profilin were required to stop elongation by AMP-PNP-actin monomers than ADP-actin monomers. High concentrations of profilin depolymerized barbed ends at a rate much faster than the spontaneous dissociation rates of Mg-ATP-, Mg-AMP-PNP-, Mg-ADP-P _i-, and Mg-ADP-actin subunits. Fitting a thermodynamic model to these data allowed us to determine the affinities of profilin and profilin-actin for barbed ends and the influence of the nucleotide bound to actin on these interactions. Profilin has a much higher affinity for ADP-actin filament barbed ends (K_d = 1 μM) than AMP-PNP-actin filament barbed ends (K _d = 226 μM). ADP-actin monomers associated with profilin bind to ADP-actin filament barbed ends 10% as fast as free ADP-actin monomers, but bound profilin does not affect the rate of association of AMP-PNP-actin monomers with barbed ends. The differences in the affinities of AMP-PNP- and ADP-bound barbed ends for profilin and profilin-actin suggest that conformations of barbed end subunits differ from those of monomers and change upon nucleotide hydrolysis and phosphate release. A structural model revealed minor steric clashes between profilin and actin subunits at the barbed end that explain the biochemical results.
机译：Profilin不仅与肌动蛋白丝的刺骨头粘合，而且抑制亚基的末端。为了解决有关具有倒钩结束的毛刺素相互作用的打开问题，我们通过全内反射荧光显微镜测量了各种浓度的Homo Sapiens Profilin 1的浓度浓度浓度的浓度。需要更高浓度的素质来通过比ADP-肌动蛋白单体通过AMP-PNP-肌动蛋白单体伸长伸长。高浓度的粒子脱色的倒数刺末端比Mg-ATP-，Mg-AMP-PNP-，Mg-ADP-P _I-和Mg-Adp-actin亚基的自发解离速率快得多。将热力学模型拟合到这些数据中，使我们能够确定用于刺末端的毛细血管和型肌动蛋白的亲和力以及核苷酸结合的致动蛋白对这些相互作用的影响。 Profilin对ADP-actin长丝杆端部（K_D =1μm）具有比AMP-PNP-肌动蛋白长丝杆（K _d =226μm）更高的亲和力。与Profilin相关的ADP-actin单体与ADP-actin长丝骨架结合10％，尽可能快地作为游离ADP-肌动蛋白单体，但结合的突发素不会影响AMP-PNP-肌动蛋白单体与倒钩端的关联率。用于Profilin和Profilin-Actin的AMP-PNP-和ADP-结合末端的亲和力的差异表明，倒钩结束子单元的构象与单体的构象不同，并在核苷酸水解和磷酸盐释放时变化。结构模型揭示了毛细血管和肌动蛋白亚基之间的次要空间冲突，解释了生物化学效果。

著录项

  • 来源
    《Biochemistry》 |2013年第37期|共11页
  • 作者

    Courtemanche N.; Pollard T.D.;

  • 作者单位

    Department of Molecular Cellular and Developmental Biology Yale University P.O. Box 208103 New Haven CT 06520-8103 United States;

    Department of Molecular Cellular and Developmental Biology Yale University P.O. Box 208103 New Haven CT 06520-8103 United States;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 生物化学;
  • 关键词

    AMP-PNP- and; Interaction of profilin; profilin-actin;

    机译：amp-pnp-和;profilin的相互作用;profilin-actin;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号