Related Experiment Video

Updated: Aug 13, 2026

Visualization of DNA Replication in the Vertebrate Model System DT40 using the DNA Fiber Technique
07:18

Visualization of DNA Replication in the Vertebrate Model System DT40 using the DNA Fiber Technique

Published on: October 27, 2011

A novel role for Cdc5p in DNA replication

C F Hardy1, A Pautz

  • 1Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. chardy@cellbio.wustl.edu

Molecular and Cellular Biology
|December 1, 1996
PubMed

Insights

The study reveals that Cdc5p, a mitotic kinase, may recruit to DNA replication origins, interacting with Dbf4p. This suggests a novel role for Polo-like kinases in DNA replication initiation.

Area of Science:

  • Molecular Biology
  • Cell Cycle Regulation
  • DNA Replication

Background:

  • DNA replication initiates at specific chromosomal origins occupied by the Origin Recognition Complex (ORC) in Saccharomyces cerevisiae.
  • Dbf4p is implicated in targeting the Cdc7p kinase to initiation complexes during the G1/S phase transition.

Purpose of the Study:

  • To investigate the potential role of Dbf4p in recruiting Cdc5p, a Polo family kinase, to DNA replication origin complexes.
  • To explore the functional interaction between Cdc5p, Cdc7p, Dbf4p, and ORC in DNA replication and cell division.

Main Methods:

  • Investigated protein-protein interactions between Dbf4p, Cdc5p, and Cdc7p using distinct domain interactions.
  • Utilized cdc5-1 mutants to assess plasmid maintenance defects and synthetic lethality with orc2-1 mutants.
  • Analyzed cell cycle regulation of Cdc5p protein levels.

Main Results:

  • Dbf4p interacts with distinct domains of both Cdc5p and Cdc7p, suggesting a scaffold function.
  • cdc5-1 mutants exhibit plasmid maintenance issues, suppressible by increased origin copy number.
  • Synthetic lethality observed in cdc5-1 orc2-1 double mutants indicates functional interdependence.
  • Cdc5p levels are cell cycle-regulated, peaking in G2/M phase.

Conclusions:

  • Cdc5p, a key mitotic kinase, likely plays a role at DNA replication origins, potentially recruited by Dbf4p.
  • These findings suggest a novel function for Polo-like kinases in the initiation of DNA replication.
  • The study highlights a potential link between mitotic progression and replication origin firing.

More Related Videos

Hybrid Ensemble and Single-molecule Assay to Image the Motion of Fully Reconstituted CMG10:11

Hybrid Ensemble and Single-molecule Assay to Image the Motion of Fully Reconstituted CMG

Published on: July 26, 2024

Single-Molecule Real-Time Visualization of DNA Unwinding by CMG Helicase07:37

Single-Molecule Real-Time Visualization of DNA Unwinding by CMG Helicase

Published on: September 27, 2024

Related Concept Videos

DNA Replication02:40

DNA Replication

DNA replication involves the separation of the two strands of the double helix, with each strand serving as a template from which the new complementary strand is copied.  After replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand. This is known as semiconservative replication. The resulting DNA molecules have the same sequence and are divided equally into the two daughter cells.
Replication in Prokaryotes
DNA replication uses a large number of...
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 forks, one in...
Restarting Stalled Replication Forks02:37

Restarting Stalled Replication Forks

DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
S-Cdk Initiates DNA Replication02:38

S-Cdk Initiates DNA Replication

The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
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 forks, one in...
S-Cdk Initiates DNA Replication02:38

S-Cdk Initiates DNA Replication

The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.