中文摘要：

目的 研究TXNDC5在缺血清诱导的HeLa细胞增殖抑制过程中的作用.方法 在人HeLa细胞中分别过表达TXDNC5或用干扰小RNA （siRNA）抑制TXDNC5的表达后,对其进行正常或缺血清培养,采用Western blot法检测TXDNC5蛋白水平,荧光实时定量PCR检测TXDNC5 mRNA水平,细胞增殖检测试剂盒（MTS法）检测活细胞数,流式细胞术检测细胞周期和细胞凋亡.结果 缺血清诱导HeLa细胞增殖抑制时,TXNDC5 mRNA水平下降（P＜0.05）,蛋白水平显著升高,TXNDC5 mRNA的稳定性不受影响,而放线菌酮则可消除缺血清诱导TXNDC5蛋白水平升高的作用.在HeLa细胞中过表达TXNDC5对细胞增殖速度无影响.抑制TXNDC5的表达能减弱缺血清诱导的HeLa细胞增殖抑制（P＜0.05）,使S期细胞比例略有增加（P＜0.05）,但对细胞凋亡没有明显影响.结论 TXNDC5介导了缺血清诱导的HeLa细胞增殖抑制.

英文摘要：

Objective To investigate the role of TXNDC5 in serum starvation-induced proliferation in- hibition of HeLa cell. Methods TXNDC5 was either over-expressed or knocked down by small interfering RNA （siRNA） in HeLa cells which were then cultured in conventional medium or serum starvation medium. The pro- tein level of TXNDC5 was evaluated by Western blot analysis. The mRNA level of TXNDC5 was measured by quantitative real-time PCR. Cell growth rate was determined by cell proliferation assay kit （ MTS method） . Cell cycle distribution and apoptosis were detected by flow cytometry. Results Serum starvation mildly reduced the mRNA level of TXNDC5 （P 〈 0.05 ）, but dramatically increased the protein level of TXNDC5 in HeLa cells. The stability of TXNDC5 mRNA remained unchanged. Cycloheximide abolished the serum starvation-induced up- regulation of TXNDC5 protein. Over-expression of TXNDC5 had no effect on cell proliferation. However, sup- pression of TXNDC5 attenuated the proliferation inhibition of HeLa cell induced by serum starvation （P 〈 0. 05 ）, increased the proportion of cells in S phase （P 〈 0. 05）, but had no effect on cell apoptosis. Conelu-sion TXNDC5 mediates serum starvation-induced proliferation inhibition of HeLa cell.