受電場而極化的脂膜筏引導纖維母細胞之方向性移動

Abstract

當微生物或細胞受到電場影響而展現出順著電場方向移動，此為趨電性。許多研究指出膜蛋白的分佈狀況會影響趨電性的行為，在先前的研究中指出α2β1 integrin受電場影響而有極化的現象，且其在交流電與直流電刺激中有著相反的分佈情形，因此本研究想探討細胞膜上的微結構─脂膜筏，在纖維母細胞受交流電或直流電影響後，如何控制細胞的移動性，結果中發現，脂膜筏受電場影響而聚集，且跟α2β1素蛋白有著相似的分佈，此外，九成的α2β1素蛋白坐落在脂膜筏上，如果破壞脂膜筏會抑制纖維母細胞的趨電性行為，另外，抑制caveolin-1的基因表現也會抑制往負極向移動和RhoA的分佈，因此從本研究的研究中，可以知道脂膜筏會藉由caveolin-1影響纖維母細胞趨電性的表現。

Galvanotaxis is a phenomenon in which microorganisms migrate in response with the electric current. Most studies indicate that the redistribution of plasma membrane proteins guides cell directional motility. The previous study showed that α2β1 integrin polarizes with AC and DC electric fields. This study shows when fibroblasts are stimulated by an electric field, lipid rafts polarize and the polarization coincides with asymmetrically-distributing α2β1 integrins. Disruption of lipid rafts inhibits EF-induced directional migration. The caveolin-1 knockdown inhibits cell directional motility and RhoA polarization. The results indicate that lipid raft is a mechanosensor to EF stimulation and lipid raft polarization lead to integrin and caveolin-dependent directional migration.