tRNA体外抑制L929细胞生长的作用观察

TRANSFER RNAs INHIBIT THE GROWTH OF L929 CELLS IN VITRO

目的:探讨tRNA对不同哺乳动物细胞生长的影响。方法:L929细胞、NIH3T3细胞、MCF-7细胞和PC12细胞接种96孔板,37℃,5%CO2细胞培养箱中培养4h后,直接加入酵母tRNA,继续培养一定时间后采用MTT法检测细胞生长情况;将200μg/ml酵母tRNA加入至L929细胞中,在不同时间点观察细胞形态并收集细胞进行细胞流式分析。结果:tRNA对L929细胞有特异的抑制作用,并且表现出一定的剂量依赖性;tRNA处理后L929细胞与正常细胞相比,形态明显变大,而且突起增长;流式细胞仪分析进一步发现tRNA使细胞阻滞于S期。结论:tRNA的这种细胞生长的抑制效应可能是通过其一些小的降解片段发挥的,提示tRNA或者其降解片段可能具有调控L929细胞增殖的重要作用。

Aim： To explore the effects of tRNA on the growth of mammalian cells. Methods： L929, NIH3T3, MCF-7 and PC12 cells were seeded in 96 well culture plate individually, and incubated at 37℃ in 5 % CO2 for 4 h, the tRNAs from different species were added to the culture media individually. After certain time of incubation, the viability of the cells was evaluated by the MTT methods. Sub-confluent L929 ceils were incubated with 200μg/ml ytRNA for different times, then the cells were pooled and analyzed with flow cytometry assay. Results： tRNA specifically inhibited the growth of L929 cells in a dose-dependent manner. The sizes of tRNA-treated cells showed larger sizes and longer processes than those of untreated cells. Flow cytometric analysis further showed that most of tRNA-treated cells were arrested in S phase of the cell cycle. Conclussion ： The cell growth inhibitory effects of tRNAs were caused mainly by their degraded fragments. The results suggested that tRNA or its degraded fragments might play important roles in regulation of cell proliferation.