Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Translesion DNA Polymerases02:10

Translesion DNA Polymerases

10.2K
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
10.2K
Proofreading01:31

Proofreading

6.7K
Synthesis of new DNA molecules is carried out by the enzyme DNA polymerase, which adds nucleotides on the daughter strand complementary to the template DNA strand. DNA polymerase has a higher affinity to add the correct base and ensures fidelity during DNA replication. Furthermore,  it exhibits proofreading activity during replication, using an exonuclease domain that cuts off incorrect nucleotides from the nascent DNA strand.
Errors During Replication are Corrected by the DNA Polymerase...
6.7K
The Replisome03:01

The Replisome

34.9K
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
34.9K
Lagging Strand Synthesis01:59

Lagging Strand Synthesis

54.3K
During replication, the complementary strands in double-stranded DNA are synthesized at different rates. Replication first begins on the leading strand. Replication starts later, occurs more slowly, and proceeds discontinuously on the lagging strand.
There are several major differences between synthesis of the leading strand and synthesis of the lagging strand. 1) Leading strand synthesis happens in the direction of replication fork opening, whereas lagging strand synthesis happens in the...
54.3K
Replication in Eukaryotes02:31

Replication in Eukaryotes

172.4K
Overview
172.4K
Bacterial RNA Polymerase00:43

Bacterial RNA Polymerase

30.6K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
30.6K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Reply to Roske and Yeeles: Mismatch correction by a replicative polymerase constrained on DNA by a ring.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

The <i>E. coli</i> DnaX clamp loader sharply bends DNA to load β-clamp at nicks and small gaps.

bioRxiv : the preprint server for biology·2026
Same author

Molecular determinants of Smc5/6 association with DNA junctions.

Nature communications·2026
Same author

DNA polymerase α-primase can function as a translesion DNA polymerase.

Proceedings of the National Academy of Sciences of the United States of America·2025
Same author

The proofreading mechanism of the human leading-strand DNA polymerase ε holoenzyme.

Proceedings of the National Academy of Sciences of the United States of America·2025
Same author

The proofreading mechanism of the human leading strand DNA polymerase ε holoenzyme.

bioRxiv : the preprint server for biology·2025

Related Experiment Video

Updated: Sep 16, 2025

DNA Sequence Recognition by DNA Primase Using High-Throughput Primase Profiling
08:04

DNA Sequence Recognition by DNA Primase Using High-Throughput Primase Profiling

Published on: October 8, 2019

8.8K

DNA polymerase α-primase can function as a translesion DNA polymerase.

Ryan Mayle1, Roxana Georgescu1, Michael E O'Donnell1

  • 1HHMI and The Rockefeller University, New York, New York 10065.

Biorxiv : the Preprint Server for Biology
|July 9, 2025
PubMed
Summary

Eukaryotic Polα-primase initiates DNA replication with RNA-DNA primers. This study reveals Polα bypasses template lesions, explaining its lack of proofreading during genomic replication.

Keywords:
DNA polymerase alphaDNA repairDNA replicationDNA translesion bypassPrimaseReplication fork

More Related Videos

Kinetics of Lagging-strand DNA Synthesis In Vitro by the Bacteriophage T7 Replication Proteins
08:14

Kinetics of Lagging-strand DNA Synthesis In Vitro by the Bacteriophage T7 Replication Proteins

Published on: February 25, 2017

7.5K
Detection of Post-Replicative Gaps Accumulation and Repair in Human Cells Using the DNA Fiber Assay
10:32

Detection of Post-Replicative Gaps Accumulation and Repair in Human Cells Using the DNA Fiber Assay

Published on: February 3, 2022

6.6K

Related Experiment Videos

Last Updated: Sep 16, 2025

DNA Sequence Recognition by DNA Primase Using High-Throughput Primase Profiling
08:04

DNA Sequence Recognition by DNA Primase Using High-Throughput Primase Profiling

Published on: October 8, 2019

8.8K
Kinetics of Lagging-strand DNA Synthesis In Vitro by the Bacteriophage T7 Replication Proteins
08:14

Kinetics of Lagging-strand DNA Synthesis In Vitro by the Bacteriophage T7 Replication Proteins

Published on: February 25, 2017

7.5K
Detection of Post-Replicative Gaps Accumulation and Repair in Human Cells Using the DNA Fiber Assay
10:32

Detection of Post-Replicative Gaps Accumulation and Repair in Human Cells Using the DNA Fiber Assay

Published on: February 3, 2022

6.6K

Area of Science:

  • Molecular Biology
  • Genetics
  • Biochemistry

Background:

  • Eukaryotic DNA replication requires primase to synthesize RNA primers.
  • Polα-primase, unlike other DNA polymerases, lacks proofreading exonuclease activity.
  • The function of Polα's non-proofreading DNA polymerase subunit remains unclear.

Purpose of the Study:

  • To investigate the functional role of Polα's DNA polymerase subunit.
  • To understand why Polα lacks 3'-5' exonuclease activity despite its role in replication initiation.

Main Methods:

  • In vitro biochemical assays were used to test Polα's ability to replicate DNA past damaged template bases.
  • Comparative analysis of Polα's activity against other DNA polymerases.

Main Results:

  • Polα demonstrates a unique ability to bypass common oxidized and hydrolyzed DNA template lesions.
  • This bypass capability is specific to Polα and not observed in proofreading polymerases.

Conclusions:

  • Polα's lack of proofreading is compensated by its ability to traverse template lesions.
  • This specialized function allows for efficient initiation of DNA replication despite potential DNA damage.