细胞生长速率对青霉素酰化酶基因表达的影响

Relationship Between pac Gene Expression and Cell Growth Rate

本文报道在细胞生长的不同时期,加苯乙酸诱导pac基因表达,发现在细胞生长早期(0—24h),苯乙酸诱导pac基因表达的效应非常明显,诱导效率很高;随着时间的推延,苯乙酸诱导pac基因表达的作用逐渐减弱,在细胞生长中期(24—48h),诱导效率明显减弱;在细胞生长后期即静止期(48—72h),苯乙酸几乎诱导不出pac基因的表达。RNA-DNA点杂交检测各期细胞内青霉素酰化酶mRNA的量,也发现在生长早期诱导的细胞转录产生的pac-mRNA量很高,在生长中、后期诱导的细胞转录产生的pac-mRNA量明显减少,mRNA水平和蛋白质水平变化趋势一致。上述结果表明,苯乙酸诱导青霉素酰化酶基因表达依赖于细胞生长速率,处于生长周期不同时期的细胞,诱导产生青霉素酰化酶的能力不同,细胞生长速率对Pac基因表达的影响发生在转录水平,pac基因表达与细胞生长相偶联,提示存在一个或多个与细胞生长相偶联的因子调节着pac基因的表达。

The induction of the pac gene expression by phenyiacetic acid at different times showed that the induction effect depended on the cell growth rate. The induction was efficient at early exponential phase and became weaker at middle and late exponential phase. At stationary phase, the pac gene expression could not be induced at all.The pac gene expression was related to the cell growth rate.The results of RNA-DNA hybridization showed that cell growth rate regulated the pac gene expression at the transcriptional level. It was suggested that some regulatory factors, which were related to cell growth, were involved in the expression of pac gene and at least one of them was temperature sensitive.