Directional control of cell motility through focal adhesion positioning and spatial control of Rac activation
Directional control of cell motility through focal adhesion positioning and spatial control of Rac activation
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DOI：
10.1096/fj.07-090571
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发表时间：
2008-06-01
期刊：
影响因子：
4.8
通讯作者：
Ingber, Donald E.
中科院分区：
文献类型：
--
作者：
Xia, Nan;Thodeti, Charles K.;Ingber, Donald E.
细胞和细胞外基质（ECM）之间的局部物理相互作用影响定向细胞运动，这对组织发育，伤口修复和癌症转移至关重要。在这里，我们测试了粘着灶的精确空间定位决定细胞扩散和移动方向的可能性。NIH 3 T3细胞在圆形或线性ECM岛上培养，所述ECM岛是使用微接触印刷技术产生的，并且是1 μ m宽和各种长度（1至8 μ m），并且由1至4.5 μ m宽的非粘附屏障区域隔开。细胞可以通过改变细胞外基质的间距或类似大小的细胞外基质岛的形状来主动扩散和向特定方向移动。免疫荧光显微镜证实，粘着斑优先组装在ECM岛上方，在沿着细胞周边的粘着位点处观察到最大的染色强度。Rac-FRET分析活细胞显示，Rac成为激活后2分钟内，外周膜延伸粘附到新的ECM岛，这种激活波向外传播的细胞从岛到岛的定向方式。一个计算模型，它结合了细胞优先突出膜过程从新形成的粘着斑接触附近的区域，可以预测高精度的影响，六种不同的安排的微图案ECM岛定向细胞扩散。综上所述，这些结果表明，ECM的物理性质可能会影响定向细胞运动，通过规定细胞将形成新的焦点粘附和激活Rac，因此，管理新的膜突起将形成。
Local physical interactions between cells and extracellular matrix (ECM) influence directional cell motility that is critical for tissue development, wound repair, and cancer metastasis. Here we test the possibility that the precise spatial positioning of focal adhesions governs the direction in which cells spread and move. NIH 3T3 cells were cultured on circular or linear ECM islands, which were created using a microcontact printing technique and were 1 mu m wide and of various lengths (1 to 8 mu m) and separated by 1 to 4.5 mu m wide nonadhesive barrier regions. Cells could be driven proactively to spread and move in particular directions by altering either the interisland spacing or the shape of similar-sized ECM islands. Immunofluorescence microscopy confirmed that focal adhesions assembled preferentially above the ECM islands, with the greatest staining intensity being observed at adhesion sites along the cell periphery. Rac-FRET analysis of living cells revealed that Rac became activated within 2 min after peripheral membrane extensions adhered to new ECM islands, and this activation wave propagated outward in an oriented manner as the cells spread from island to island. A computational model, which incorporates that cells preferentially protrude membrane processes from regions near newly formed focal adhesion contacts, could predict with high accuracy the effects of six different arrangements of micropatterned ECM islands on directional cell spreading. Taken together, these results suggest that physical properties of the ECM may influence directional cell movement by dictating where cells will form new focal adhesions and activate Rac and, hence, govern where new membrane protrusions will form.