The initiator function of DnaA protein is negatively regulated by the sliding clamp of the E-coli chromosomal replicase
The initiator function of DnaA protein is negatively regulated by the sliding clamp of the E-coli chromosomal replicase
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DOI：
10.1016/s0092-8674(00)81222-2
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发表时间：
1998-07-10
期刊：
影响因子：
64.5
通讯作者：
Sekimizu, K
中科院分区：
文献类型：
--
作者：
Katayama, T;Kubota, T;Sekimizu, K
DNA聚合酶III的β亚基对启动蛋白DNA的负调控至关重要。dna失活是通过与dna结合的ATP加速水解发生的；产生的adp - dna无法开始复制。β亚基促进DNA失活的能力取决于其作为DNA滑动钳的组装，并且必须伴随着部分纯化的因子，即IdaB蛋白。在IdaB和DNA聚合酶III存在的情况下，DNA的失活会被DNA合成进一步刺激，这表明引发物的失活与复制之间存在密切的联系。在体内，dna主要以β亚基依赖的方式呈现ADP形式。因此，启动物受到复制酶的负向调控，这一机制可能是有效控制复制周期的关键。
The beta subunit of DNA polymerase III is essential far negative regulation of the initiator protein, DnaA. DnaA inactivation occurs through accelerated hydrolysis of ATP bound to DnaA; the resulting ADP-DnaA fails to initiate replication. The ability of beta subunit to promote DnaA inactivation depends on its assembly as a sliding clamp on DNA and must be accompanied by a partially purified factor, IdaB protein. DnaA inactivation in the presence of IdaB and DNA polymerase III is further stimulated by DNA synthesis, indicating close linkage between initiator inactivation and replication. In vivo, DnaA predominantly takes on the ADP form in a beta subunit-dependent manner. Thus, the initiator is negatively regulated by action of the replicase, a mechanism that may be key to effective control of the replication cycle.