REGULATION OF TRANSCRIPTION OF THE CHROMOSOMAL DNAA GENE OF ESCHERICHIA-COLI
REGULATION OF TRANSCRIPTION OF THE CHROMOSOMAL DNAA GENE OF ESCHERICHIA-COLI
复制标题
DOI：
10.1007/bf02428040
复制
发表时间：
1986-01-01
期刊：
影响因子：
--
通讯作者：
MESSER, W
中科院分区：
文献类型：
--
作者：
KUCHERER, C;LOTHER, H;MESSER, W
通过比较S1分析，我们研究了染色体dnaA基因转录的体内调节，该基因编码染色体起点复制启动所必需的蛋白质。蛋白indnaA突变体的失活导致去阻遏，而过量的DnaA蛋白（存在DnaA过量产生质粒）导致dnaA转录的阻遏。这两种dnaA启动子都受到自身调节，允许转录效率调节至少20倍。通过引入质粒增加细胞中的iC序列的数量（DnaA结合位点的数量）导致转录的去抑制。自动调节和结合toriC表明，DnaA蛋白发挥了重要作用，在调节频率的起始toriC。dnaA2启动子的转录效率在dammethylation缺失的情况下降低，dammethylation参与了转录的调节。
By comparative S1 analysis we investigated the in vivo regulation of transcription of the chromosomaldnaAgene coding for a protein essential for the initiation of replication at the chromosomal origin. Inactivation of the protein indnaAmutants results in derepression, whereas excess DnaA protein (presence of a DnaA overproducing plasmid) leads to repression ofdnaAtranscription. BothdnaApromoters are subject to autoregulation allowing modulation of transcriptional efficiency by at least 20-fold. Increasing the number oforiCsequences (number of DnaA binding sites) in the cell by introducingoriCplasmids leads to a derepression of transcription. Autoregulation and binding tooriCsuggest that the DnaA protein exerts a major role in the regulation of the frequency of initiation atoriC. The efficiency of transcription of thednaA2promoter is reduced in the absence ofdammethylation, which is involved in the regulation oforiCreplication.