DNA primase acts as a molecular brake in DNA replication

@article{Lee2006DNAPA,
  title={DNA primase acts as a molecular brake in DNA replication},
  author={Jong-Bong Lee and Richard K. Hite and Samir M. Hamdan and X. Sunney Xie and Charles C. Richardson and Antoine M. van Oijen},
  journal={Nature},
  year={2006},
  volume={439},
  pages={621-624}
}
A hallmark feature of DNA replication is the coordination between the continuous polymerization of nucleotides on the leading strand and the discontinuous synthesis of DNA on the lagging strand. [] Key Result We observe the synthesis of primers on the lagging strand to cause transient pausing of the highly processive leading-strand synthesis. In the presence of both leading- and lagging-strand synthesis, we observe the formation and release of a replication loop on the lagging strand. Before loop formation…

Coordinating DNA replication by means of priming loop and differential synthesis rate

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Dynamics of DNA replication loops reveal temporal control of lagging-strand synthesis

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Recently developments in single-molecule techniques have enabled the direct observation of these processes and have greatly contributed to a better understanding of the dynamic nature of the replication fork.

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The T4 bacteriophage encodes eight proteins, which are sufficient to carry out coordinated leading and lagging strand DNA synthesis, and the formation of a holoenzyme complex composed of the polymerase and a processivity clamp is studied.

E. coli DNA replication in the absence of free β clamps

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Motors, switches, and contacts in the replisome.

The replisome of bacteriophage T7 contains a minimum of proteins, thus facilitating its study, and this review describes the molecular motors and coordination of their activities, with emphasis on the T7 replisomes.

Discrete interactions between bacteriophage T7 primase-helicase and DNA polymerase drive the formation of a priming complex containing two copies of DNA polymerase.

Results indicate that the T7 primase-helicase specifically engages two copies of DNA polymerase, which would allow the coordination of leading and lagging strand synthesis at a replication fork.

Single-molecule studies of polymerase dynamics and stoichiometry at the bacteriophage T7 replication machinery

This study uses single-molecule fluorescence methods to visualize the dynamics with which individual DNA polymerases, the replication protein responsible for DNA synthesis, associate with and dissociate from the replication machinery, and suggests that lagging-strand polymerases are exchanged at a frequency similar to that of Okazaki fragment synthesis.

Single-molecule studies of fork dynamics in Escherichia coli DNA replication

Modulation of DnaB helicase activity through the interaction with DnaG suggests a mechanism that prevents leading-strand synthesis from outpacing lagging-Strand synthesis during slow primer synthesis on the lagging strand.

Single-molecule studies of fork dynamics in Escherichia coli DNA replication

Modulation of DnaB helicase activity through the interaction with DnaG suggests a mechanism that prevents leading-strand synthesis from outpacing lagging-Strand synthesis during slow primer synthesis on the lagging strand.
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