Microtubule-targeting-dependent reorganization of filopodia
Microtubule-targeting-dependent reorganization of filopodia
复制标题
DOI：
10.1242/jcs.003913
复制
发表时间：
2007-04-01
影响因子：
4
通讯作者：
Borisy, Gary G.
中科院分区：
文献类型：
--
作者：
Schober, Joseph M.;Komarova, Yulia A.;Borisy, Gary G.
微管系统和肌动蛋白细胞骨架之间的相互作用已经成为空间调节细胞伸出和缩回活动所需的基本过程。在我们目前的研究中，数字荧光图像的分析揭示了微管在B16F1黑色素瘤细胞和成纤维细胞中对丝状伪足的靶向作用。我们研究了针对丝状伪足重组的功能后果，并研究了微管可能被引导到丝状伪足或与丝状伪足相互作用的机制。活细胞成像研究表明，在板状伪足翅膀的靶向事件与丝状伪足转向板状伪足中线和丝状伪足合并时间相关。用诺考达唑靶向快速解偶联减少丝状伪足合并事件并增加丝状伪足密度。全内反射荧光显微镜鉴定微管腹侧表面附近和向上运动的目标丝状伪足。研究了粘附位点和微管蛋白在靶向中的作用。没有观察到粘附位点与微管靶向丝状伪足的相关性，微管加端蛋白的消耗没有显著改变靶向频率。我们建议，微管的目标丝状伪足，独立的焦点粘连和加端蛋白，导致丝状伪足运动和微管调节丝状伪足密度板状伪足翅膀通过丝状伪足合并事件。
Interaction between the microtubule system and actin cytoskeleton has emerged as a fundamental process required for spatial regulation of cell protrusion and retraction activities. In our current studies, analysis of digital fluorescence images revealed targeting of microtubules to filopodia in B16F1 melanoma cells and fibroblasts. We investigated the functional consequence of targeting on filopodia reorganization and examined mechanisms by which microtubules may be guided to, or interact with, filopodia. Live cell imaging studies show that targeting events in lamellipodia wings temporally correlated with filopodia turning toward the lamellipodium midline and with filopodia merging. Rapid uncoupling of targeting with nocodazole decreased filopodia merging events and increased filopodia density. Total internal reflection fluorescence microscopy identified microtubules near the ventral surface and upward movement of targeted filopodia. The role of adhesion sites and microtubule plusend proteins in targeting was investigated. Correlation of adhesion sites with microtubule targeting to filopodia was not observed and depletion of microtubule plus-end proteins did not significantly alter targeting frequency. We propose that microtubules target filopodia, independent of focal adhesions and plus-end proteins, causing filopodia movement and microtubules regulate filopodia density in lamellipodia wings through filopodia merging events.