DNA

Sophie L Williams1, Corella S Casas-Delucchi1, Federica Raguseo2,3

  • 1Genome Replication Lab, Division of Cancer Biology, Institute of Cancer Research, Chester Beatty Laboratories, London, UK.

The EMBO journal
|October 2, 2023
PubMed
概括

像G-四复合体 (G4s) 和介质动机 (iMs) 这样的DNA二次结构可以阻止DNA复制. 皮夫1酶能够解决这些结构,防止基因组的不稳定性和复制压力.

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The DNA Replication Fork01:02

The DNA Replication Fork

An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork.   Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication...
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Restarting Stalled Replication Forks02:37

Restarting Stalled Replication Forks

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DNA Topoisomerases02:02

DNA Topoisomerases

Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. ...
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Homologous Recombination02:31

Homologous Recombination

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Single-Strand DNA Binding Proteins01:03

Single-Strand DNA Binding Proteins

For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...
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Replication in Prokaryotes01:32

Replication in Prokaryotes

DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins bind to the single origin of replication (ori) on the cell's circular chromosome. Replication then proceeds around the entire circle of the chromosome in each direction from the two replication forks, resulting in two DNA molecules.
Many Proteins Work Together to Replicate the Chromosome
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