Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Inhibitors of Bacterial DNA Synthesis

Inhibitors of Bacterial DNA Synthesis

Bacterial pathogens depend on precise and efficient DNA replication to sustain infection. Two type II topoisomerases—DNA gyrase and topoisomerase IV—are critical to this process, as they resolve DNA supercoiling and unlink chromosomes during replication. Fluoroquinolones, synthetic derivatives of quinolones, exploit this mechanism by stabilizing the transient DNA–enzyme cleavage complex, preventing strand religation, and causing lethal double-strand breaks. These antibiotics are selectively...

DNA Topoisomerases

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. Type I...

Fixing Double-strand Breaks

Fixing Double-strand Breaks

The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...

Restarting Stalled Replication Forks

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...

DNA Damage can Stall the Cell Cycle

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...

DNA Damage Can Stall the Cell Cycle

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...

You might also read

Related Articles

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

Sort by

Same author

Influence of intramolecular interactions and transition state energetics on the strain-promoted azide-alkyne cycloaddition of 2-aminobenzenesulfonamide-containing cyclononynes.

RSC advances·2026

Same author

UDP-glucuronosyltransferase 1A9 function is mediated by the two C-terminal lysine residues and proper mobility/flexibility of the cytoplasmic tail.

Biochemical and biophysical research communications·2025

Same author

Dihydropyrazine activates the CAMKK2-AMPK-ULK1 signaling pathway in human hepatoma HepG2 cells.

The Journal of toxicological sciences·2025

Same author

Disulfide bond-mediated stabilization of the oligomers of UDP-glucuronosyltransferase 2B7.

The Journal of biological chemistry·2025

Same author

Utility of Discrepancies Between Friedewald and Martin Equations in Predicting Pathogenic Variants of Familial Hypercholesterolemia in Children.

Circulation journal : official journal of the Japanese Circulation Society·2025

Same author

Adult severe community-acquired pneumonia with bloodstream infection caused by ψUSA 300: A case report.

Diagnostic microbiology and infectious disease·2024

Search research articles

Related Experiment Video

Updated: Jun 12, 2026

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

Published on: May 12, 2023

Phenyl-substituted dihydropyrazines with DNA strand-breakage activity.

Shigeru Ito¹, Shinji Takechi, Kazuhide Nakahara

¹Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University.

Chemical & Pharmaceutical Bulletin

|June 5, 2010

Summary

Researchers synthesized novel monophenyl-substituted dihydropyrazines and investigated their DNA strand-breakage effects. This study explores the biological impact of these compounds, comparing phenyl- and methyl-substituted variants.

More Related Videos

Single Molecule Analysis of Laser Localized Psoralen Adducts

Single Molecule Analysis of Laser Localized Psoralen Adducts

Published on: April 20, 2017

Assessment of DNA Double Strand Break Repair Activity Using High-throughput and Quantitative Luminescence-Based Reporter Assays

Assessment of DNA Double Strand Break Repair Activity Using High-throughput and Quantitative Luminescence-Based Reporter Assays

Published on: June 14, 2024

Related Experiment Videos

Last Updated: Jun 12, 2026

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

Published on: May 12, 2023

Single Molecule Analysis of Laser Localized Psoralen Adducts

Single Molecule Analysis of Laser Localized Psoralen Adducts

Published on: April 20, 2017

Assessment of DNA Double Strand Break Repair Activity Using High-throughput and Quantitative Luminescence-Based Reporter Assays

Assessment of DNA Double Strand Break Repair Activity Using High-throughput and Quantitative Luminescence-Based Reporter Assays

Published on: June 14, 2024

Area of Science:

Medicinal Chemistry
Molecular Biology
Genetics

Background:

Dihydropyrazines are heterocyclic compounds with diverse biological activities.
Previous studies suggest potential for dihydropyrazines in inducing apoptosis and mutagenesis.
Understanding structure-activity relationships is crucial for developing novel therapeutic agents.

Purpose of the Study:

To synthesize novel monophenyl-substituted dihydropyrazines (Ph-DHP-1 to 4).
To investigate the biological effects of synthesized compounds, focusing on DNA strand-breakage.
To compare the biological impact of phenyl-substituted dihydropyrazines with methyl-substituted analogs (Me-DHP-1).

Main Methods:

Chemical synthesis of monophenyl-substituted dihydropyrazines.
Biological assays to assess DNA strand-breakage induction.
Comparative analysis of structure-activity relationships between phenyl- and methyl-substituted dihydropyrazines.

Main Results:

Successful synthesis of four monophenyl-substituted dihydropyrazines.
Demonstration of DNA strand-breakage activity by the synthesized compounds.
Identification of differences in biological effects between phenyl- and methyl-substituted dihydropyrazines.

Conclusions:

Monophenyl-substituted dihydropyrazines exhibit DNA strand-breakage properties.
The substitution pattern (phenyl vs. methyl) influences the biological activity.
These findings contribute to understanding the genotoxic potential of dihydropyrazine derivatives.