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Vincent E Saxton J Baker-Glenn C Moal I Hirst JD Pattenden G Shaw PE 《Cellular and molecular life sciences : CMLS》2007,64(4):487-497
Several marine macrolide toxins act as potent and specific actin-severing molecules. Recent elucidation of their stereochemistries
and modes of interaction with actin has allowed the syntheses of bioactive analogues. Here we used synthetic analogues in
a structure-function analysis of ulapualide A, a trisoxazole-based macrolide. Ulapualide A harboured potent actin-depolymerising
activity both in cells and in vitro. Its synthetic diastereoisomer was three orders of magnitude less active than the natural toxin and synthetic macrolide fragments
lacked actin-capping/ severing activity altogether. Modulation of serum response factor (SRF)-dependent gene expression, as
described for other actin-binding toxins, was also examined. Specific changes in response to ulapualide A were not observed,
primarily due to its profound effects on cytoskeletal integrity and cell adhesion. Several synthetic fragments of ulapualide
A also had no effect on SRF-dependent gene expression. However, inhibition was observed with a molecule corresponding to the
extended aliphatic side chain of halichondramide, a structurally related macrolide. These findings indicate that side-chain
derivatives of trisoxazole-based macrolides may serve to uncouple gene-regulatory events from actin dynamics.
E. Vincent and J. Saxton: These two authors contributed equally
Received 27 September 2006; received after revision 30 November 2006; accepted 8 January 2007 相似文献
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张春华 《科技情报开发与经济》2003,13(3):222-223
通过对高压进线柜的改进,避免了供电系统的越级跳闸事故,进一步完善了继电保护,提高了供电系统的可靠性,为设备的正常运行提供了可靠的保障。 相似文献
54.
谭云亮 《山东科技大学学报(自然科学版)》1991,(2)
本文通过分析老顶与直接顶间作用力大小和分布,研究了老顶运动状态对直接顶断裂位置的影响,提出“Q-判据”,为进一步研究控制直接顶断裂位置提供依据。 相似文献
55.
老顶边界条件下采场矿压显现规律及直接顶破坏模式 总被引:3,自引:0,他引:3
运用数值计算方法,分析了老顶在断裂前后及不同来压步距时对采场围岩的位移及应力状态的影响。为揭示采场顶板的稳定性提供了依据。 相似文献
56.
基于六个理论模式,本文分析了与外语学习从输入到输出密切相关的语言、动机及情感反馈;及时的、明晰反馈是最为直接的、处于中心地位的反馈,要求教师投入工作,满足学习者对反馈的渴望与期盼心理,触发其动机与情感反馈,最终三者合力作用。为期六个月的实证研究在一定程度上肯定了该反馈的重要作用。反馈机制的研究为观察外语教学活动、评估外语教学质量提供了新视角。 相似文献
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纯甜玉米虽然籽粒含糖分高,但因胚乳缺陷而使其出苗晚,出苗率低,幼苗生长弱,影响产量和经济效益。通过异型玉米花粉直感产生的饱满籽粒,可以提高出苗率,苗期长势好,提高产量和经济效益,且可改善甜玉米的品质。 相似文献
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涉及对高强混凝土受弯构件在长驻荷载作用下瞬间变形和徐变变形计算机程序设计。构件可以是任意截面形状,截面尺寸,同时设有受拉和受压钢筋。提高了工作效率,可应用在教学科研和工程设计中。 相似文献
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本文建立了一个改进的位级数计算模型,使多机相关任务调度中有大量直接后继任务者能尽快投入运行.这样,可使较多的任务提前就绪,以减少处理机的等待.文中最后给出一个示例,并作了简要分析 相似文献