Regulation of the Escherichia coli rmf gene encoding the ribosome modulation factor: growth phase‐ and growth rate‐dependent control.
Regulation of the Escherichia coli rmf gene encoding the ribosome modulation factor: growth phase‐ and growth rate‐dependent control.
复制标题
编码核糖体调节因子的大肠杆菌 rmf 基因的调节：生长阶段和生长速率依赖性控制。
作者：
M. Yamagishi;Hiroshi Matsushima;A. Wada;Masayuki Sakagami;N. Fujita;A. Ishihama
核糖体调节因子（RMF）是一种与1000s核糖体二聚体特异性相关的蛋白质，在大肠杆菌细胞从指数生长过渡到固定生长阶段时开始积累。从大肠杆菌基因组21.8 min区克隆出编码rmf蛋白55个氨基酸残基的结构基因rmf，并对其进行了测序。虽然rmf在快速生长的指数期细胞中沉默，但随着生长过渡到静止期，高水平的转录发生了。在缓慢生长条件下，rmf在指数期也有表达，且rmf的表达与细胞生长速率呈反比关系。因此，rmf的表达谱与构成翻译装置的核糖体成分和核糖体相关蛋白的基因相反。katF基因产物，固定相特异性sigma因子，不需要用于rmf的表达。在固定期，rmf的破坏导致核糖体二聚体的丢失和细胞活力的降低。
Ribosome modulation factor (RMF) is a protein specifically associated with 100S ribosome dimers which start to accumulate in Escherichia coli cells upon growth transition from exponential to stationary phase. The structural gene, rmf, encoding the 55 amino acid residues RMF protein has been cloned from the 21.8 min region of the E. coli genome and sequenced. While rmf was silent in rapidly growing exponential phase cells, a high level of transcription took place concomitantly with the growth transition to stationary phase. Under slow growth conditions, rmf was expressed even in exponential phase and there was an inverse relationship between the expression of rmf and the cell growth rate. Thus, the expression profile of rmf is contrary to those of genes for ribosomal components and ribosome‐associated proteins constituting the translational apparatus. The katF gene product, a stationary phase‐specific sigma factor, was not required for the expression of rmf. Disruption of rmf resulted in loss of ribosome dimers and reduction of cell viability during stationary phase.