Rv0004 is a new essential member of the mycobacterial DNA replication machinery.
Rv0004 is a new essential member of the mycobacterial DNA replication machinery.
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DOI：
10.1371/journal.pgen.1007115
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发表时间：
2017-11
期刊：
影响因子：
4.5
通讯作者：
Stallings CL
中科院分区：
文献类型：
--
作者：
Mann KM;Huang DL;Hooppaw AJ;Logsdon MM;Richardson K;Lee HJ;Kimmey JM;Aldridge BB;Stallings CL
DNA复制是生命的基础，但对细菌DNA复制的详细了解在大肠杆菌和枯草芽孢杆菌之外是有限的。尽管在大肠杆菌和枯草芽孢杆菌中解旋酶装载物或启动蛋白DNA的调节因子对DNA复制至关重要，但包括分枝杆菌在内的许多细菌没有编码已鉴定的同源物。在这项研究中，我们发现来自人类结核分枝杆菌的一种以前未被表征的蛋白质Rv0004对细菌活力至关重要，Rv0004的缺失导致细胞周期进程受阻。采用遗传和生化相结合的方法，我们发现Rv0004在DNA复制中发挥作用，与DNA和复制解旋酶DnaB相互作用，并影响DnaB- dnaa复合物的形成。我们还在Rv0004中发现了一个保守结构域，预计其结构类似于dna的n端蛋白-蛋白相互作用结构域。Rv0004的dna n端样结构域内单个保守色氨酸的突变导致与Rv0004缺失时观察到的表型相似，并可能影响Rv0004与DnaB的关联。此外，在Rv0004缺失期间使用活细胞成像，我们发现了DNA复制在协调分枝杆菌细胞分裂和细胞大小方面以前未被认识到的作用。总之，我们的数据支持Rv0004编码最近在大肠杆菌和枯草芽孢杆菌中缺乏DnaC-DnaI解旋酶装载器的大多数细菌中发现的DciA家族蛋白的同源物。因此，本文阐明的Rv0004的机制可能适用于其他DciA同源物，并揭示了即使在最保守的生物过程中细菌策略的多样性。DNA是一种编码生物体所有遗传信息的分子。为了将基因传递给下一代，DNA必须首先通过一个称为DNA复制的过程进行复制。大多数关于细菌DNA复制的初步研究是在大肠杆菌和枯草芽孢杆菌中进行的。虽然这些研究提供了非常丰富的信息，但人们越来越认识到，在最基本的过程中，更遥远的细菌已经与这些生物分道扬镳。分枝杆菌是一组细菌，包括人类病原体结核分枝杆菌，与大肠杆菌和枯草芽孢杆菌有远亲关系，并且缺乏这些模式生物中用于DNA复制的一些蛋白质。在这项研究中，我们发现分枝杆菌中一种以前未被鉴定的蛋白质，名为Rv0004，对细菌的生存能力和参与DNA复制至关重要。Rv0004在大多数细菌中是保守的，但在大肠杆菌和枯草芽孢杆菌中不存在。由于Rv0004对分枝杆菌的生存能力至关重要，因此本研究既确定了抗生素治疗的未来靶点，又扩展了我们对细菌DNA复制策略多样性的了解，这可能适用于其他生物体。
DNA replication is fundamental for life, yet a detailed understanding of bacterial DNA replication is limited outside the organisms Escherichia coli and Bacillus subtilis. Many bacteria, including mycobacteria, encode no identified homologs of helicase loaders or regulators of the initiator protein DnaA, despite these factors being essential for DNA replication in E. coli and B. subtilis. In this study we discover that a previously uncharacterized protein, Rv0004, from the human pathogen Mycobacterium tuberculosis is essential for bacterial viability and that depletion of Rv0004 leads to a block in cell cycle progression. Using a combination of genetic and biochemical approaches, we found that Rv0004 has a role in DNA replication, interacts with DNA and the replicative helicase DnaB, and affects DnaB-DnaA complex formation. We also identify a conserved domain in Rv0004 that is predicted to structurally resemble the N-terminal protein-protein interaction domain of DnaA. Mutation of a single conserved tryptophan within Rv0004’s DnaA N-terminal-like domain leads to phenotypes similar to those observed upon Rv0004 depletion and can affect the association of Rv0004 with DnaB. In addition, using live cell imaging during depletion of Rv0004, we have uncovered a previously unappreciated role for DNA replication in coordinating mycobacterial cell division and cell size. Together, our data support that Rv0004 encodes a homolog of the recently identified DciA family of proteins found in most bacteria that lack the DnaC-DnaI helicase loaders in E. coli and B. subtilis. Therefore, the mechanisms of Rv0004 elucidated here likely apply to other DciA homologs and reveal insight into the diversity of bacterial strategies in even the most conserved biological processes. DNA is the molecule that encodes all of the genetic information of an organism. In order to pass genes onto the next generation, DNA has to first be copied through a process called DNA replication. Most of the initial studies on bacterial DNA replication were performed in Escherichia coli and Bacillus subtilis. While these studies were very informative, there is an increasing appreciation that more distantly related bacteria have diverged from these organisms in even the most fundamental processes. Mycobacteria, a group of bacteria that includes the human pathogen Mycobacterium tuberculosis, are distantly related to E. coli and B. subtilis and lack some of the proteins used for DNA replication in those model organisms. In this study, we discover that a previously uncharacterized protein in Mycobacteria, named Rv0004, is essential for bacterial viability and involved in DNA replication. Rv0004 is conserved in most bacteria but is absent from E. coli and B. subtilis. Since Rv0004 is essential for mycobacterial viability, this study both identifies a future target for antibiotic therapy and expands our knowledge on the diversity of bacterial DNA replication strategies, which may be applicable to other organisms.
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影响因子：
3.6
作者：
Garner AL;Weiss LA;Manzano AR;Galburt EA;Stallings CL
通讯作者：
Stallings CL
影响因子：
4.8
作者：
Abe, Yoshito;Jo, Takaaki;Ueda, Tadashi
通讯作者：
Ueda, Tadashi
DOI：
10.1073/pnas.0913551107
发表时间：
2010-03-16
影响因子：
11.1
作者：
Gordon, Blair R. G.;Li, Yifei;Liu, Jun
通讯作者：
Liu, Jun
影响因子：
64.5
作者：
Boshoff, HIM;Reed, MB;Mizrahi, V
通讯作者：
Mizrahi, V
影响因子：
16.6
作者：
Bhowmick, Tuhin;Ghosh, Soumitra;Nagaraja, Valakunja
通讯作者：
Nagaraja, Valakunja