S100A4蛋白对N2a细胞突起生长及骨架蛋白Tubulin聚合的影响

Effect of S100A4 Protein on Neurite Outgrowth and Tubulin Polymerization in N2a Cells

目的:观察S100A4蛋白对N2a细胞突起生长及细胞内骨架蛋白tubulin聚合的影响。方法:在N2a细胞培养基中加入S100A4蛋白(A组)或DMSO(B组),使其终浓度为5μmol/L,观察0、12、24及36h时间点N2a细胞突起的生长情况,测量突起长度,采用免疫印迹法检测N2a细胞内骨架蛋白tubulin的聚合情况。结果:2组孵育12h时,N2aA组细胞胞体均增大,部分细胞长出短小突起差异无统计意义;24h时,A组的大部分N2a细胞生长出2～5个突起,平均突起长度较B组更长(P<0.05);36h时A组部分N2a细胞突起交织成网络,且较B组发达(P<0.05)。免疫印迹检测显示,A组N2a细胞12、24及36h,细胞浆内未聚合的tubulin含量较0h时减少(P<0.05),而B组N2a细胞内未聚合tubulin含量无明显改变。结论:S100A4蛋白能增加胞浆内骨架蛋白tubulin的聚合,促进N2a细胞突起的生长。

Objective： To study the effects of S100A4 protein on neurite outgrowth and tubulin polymerization in N2a cells.Methods： N2a cells were cultured in vitro,and treated with 5 μmol/L S100A4 protein.Neurite outgrowth in N2a cells was examined morphologically at 0,12,24 and 36 h.The mount of polymerized tubulin was determined by Western blotting.Results： At 12th,24th and 36th hour after the culture with 5 μmol/L S100A4 protein or DMSO,neurite outgrowth in N2a cells was observed.Neurite outgrowth was significantly greater in S100A4 protein-treated N2a cells than in DMSO-treated controls（P〈0.05）.The formation of neurite network was also observed in S100A4 protein group at 36th hour.Furthermore,5 μmol/L S100A4 protein decreased the mount of depolymerizated tubulin compared to DMSO at 12th,24th and 36th hour.The mount of GAPDH protein had no significant change in S100A4 protein group and DMSO group.Conclusion： The results suggest that 5 μmol/L S100A4 protein can improve neurite outgrowth through inhibiting microtubule depolymerization and promoting tubulin polymerization in vitro.