Spatiotemporal dynamics of actin-rich adhesion microdomains: influence of substrate flexibility
Spatiotemporal dynamics of actin-rich adhesion microdomains: influence of substrate flexibility
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DOI：
10.1242/jcs.02838
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发表时间：
2006-05-01
影响因子：
4
通讯作者：
Planus, Emmanuelle
中科院分区：
文献类型：
--
作者：
Collin, Olivier;Tracqui, Philippe;Planus, Emmanuelle
在这项研究中，我们分析了特定的富肌动蛋白结构的形成和动力学称为足质体。足小体是非常动态的准时粘附位点，与肌动蛋白细胞骨架紧密相连。底物的力学特性正在成为细胞反应中锚定依赖过程的重要物理调节剂。我们研究了底物柔韧性对足小体动态特性的影响。我们使用小鼠NIH-3T3成纤维细胞，转染gfp -肌动蛋白，并在不同硬度的聚丙烯酰胺胶原包被底物上培养。细胞形态的静态和动态特征与光流分析的动态动力学相关联表明：(1)它们具有恒定的结构特性，即它们的形状因子和宽度不随底物的柔韧性而改变；(2)足质体的寿命和它们之间的平均最小距离取决于底物的灵活性；(3)足质体莲座的位移速度存在差异。此外，莲座有时以周期性涌现的f-肌动蛋白结构出现，这表明一个两级自组织过程可能首先驱动足小体簇的形成，其次驱动这些簇组织成振荡环。这些动态特征为研究足小体作为机械感觉结构的潜在功能提供了新的视角。
In this study we analyse the formation and dynamics of specific actin-rich structures called podosomes. Podosomes are very dynamic punctual adhesion sites tightly linked to the actin cytoskeleton. Mechanical properties of substrates are emerging as important physical modulators of anchorage-dependent processes involved in the cellular response. We investigate the influence of substrate flexibility on the dynamic properties of podosomes. We used mouse NIH-3T3 fibroblasts, transfected with GFP-actin and cultured on polyacrylamide collagen-coated substrates of varying stiffness. Static and dynamic features of cell morphologies associated with an optical flow analysis of the dynamics of podosomes revealed that: (1) they have constant structural properties, i.e. their shape factor and width do not change with the substrate flexibility; (2) the lifespan of podosomes and mean minimum distance between them depend on the substrate flexibility; (3) there is a variation in the displacement speed of the rosette of podosomes. Moreover, the rosettes sometimes appear as periodically emergent F-actin structures, which suggests that a two-level self-organisation process may drive first, the formation of clusters of podosomes and second, the organisation of these clusters into oscillating rings. Such dynamic features give new perspectives regarding the potential function of podosomes as mechanosensory structures.