Coherence of directional sensing, polarity, and motility in collective cell migration

趋化性是细胞对环境反应的基本功能之一。我们研究了多细胞对黏菌盘状盘齿钢霉趋化性的影响。定量分析了聚集过程中的迁移行为。研究发现，含有不同Tgr蛋白的细胞在接触后几分钟内就会分离，而含有相同蛋白的细胞则会聚集在一起。被相同类型包围的细胞移动得更快，并与其他细胞的极性对齐。这种协调行为仅在两个从聚集体分离的细胞中观察到。综上所述，通过Tgr蛋白的自我/非自我识别调节集体迁移行为。我们还开发了一种微流体系统来人工产生时空化学引诱场。使用该系统，我们证明了细胞能够在这种化学引诱剂场中定向迁移。

Chemotaxis is one of basic cellular functions to response to environment. We have studied multicellular effect on chemotaxis in slime mold Dictyostelium discoideum. Migration behaviors during aggregation were analyzed quantitatively. It was found that cells harboring different Tgr proteins separate within a few minutes after contact, while cells harboring the same proteins migrated together. Cells surrounded by the same type moved faster and aligned polarities with others. Such coordinated behaviors were observed in only two cells isolated from aggregate. Taken together, self/non-self recognition via Tgr proteins modulates collective migration behavior. We also developed a microfluidics system to generate spatio-temporal chemoattractant field artificially. Using this system, we demonstrated cells were able to migrate directionally in such chemoattractant field.