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

Circadian Rhythms and Gene Regulation02:19

Circadian Rhythms and Gene Regulation

4.0K
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent...
4.0K
Prokaryotic Transcriptional Activators and Repressors01:58

Prokaryotic Transcriptional Activators and Repressors

20.9K
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
20.9K
RNA Polymerase II Accessory Proteins02:36

RNA Polymerase II Accessory Proteins

9.2K
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
9.2K
Positive Regulator Molecules01:45

Positive Regulator Molecules

105.9K
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
105.9K
Cooperative Binding of Transcription Regulators02:13

Cooperative Binding of Transcription Regulators

6.4K
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome.  Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form...
6.4K
Operons02:09

Operons

48.9K
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by...
48.9K

You might also read

Related Articles

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

Sort by
Same author

Linking UV-induced DNA damage with base pair sequences.

bioRxiv : the preprint server for biology·2026
Same author

Ruling Out E/Z Isomerization in the Inverted Solvatochromism of Brooker's Merocyanine.

The journal of physical chemistry letters·2026
Same author

A quantum-mechanical framework for million-atom scale biological systems.

Communications chemistry·2026
Same author

From nullomers to abundant motifs: Fractals, CpG Bias, and Chargaff's rules in genomic sequences.

Bio Systems·2025
Same author

Excited-State Relaxation Pathways of 4-Aminobiphenyl-2-Pyrimidine Derivatives: An Ultrafast Perspective.

The journal of physical chemistry. A·2025
Same author

Unified description of thermal and nonthermal laser-induced ultrafast structural changes in materials.

Scientific reports·2024

Related Experiment Video

Updated: Jun 21, 2025

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells
11:56

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells

Published on: September 28, 2017

9.8K

Biological Rhythms Generated by a Single Activator-Repressor Loop with Inhomogeneity and Diffusion.

Pablo Rojas1, Oreste Piro1,2,3, Martin E Garcia1

  • 1Theoretical Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Kassel, Germany.

Physical Review Letters
|July 12, 2024
PubMed
Summary
This summary is machine-generated.

A simple biochemical reaction pair with spatially separated reaction sites can generate sustained biological oscillations. This finding simplifies models of circadian rhythms and inspires new in vitro clock designs.

More Related Videos

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
06:53

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Published on: November 11, 2016

8.3K
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
10:38

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

Published on: September 27, 2012

22.4K

Related Experiment Videos

Last Updated: Jun 21, 2025

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells
11:56

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells

Published on: September 28, 2017

9.8K
Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
06:53

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

Published on: November 11, 2016

8.3K
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
10:38

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

Published on: September 27, 2012

22.4K

Area of Science:

  • Biochemistry
  • Systems Biology
  • Biophysics

Background:

  • Traditional models of circadian rhythms rely on complex, multi-step negative-feedback loops within well-mixed compartments.
  • These models often treat spatial transport as additional reaction steps, increasing complexity.
  • Existing models require multiple intermediate reaction steps to produce oscillations.

Purpose of the Study:

  • To demonstrate that a minimal biochemical system can generate sustained oscillations.
  • To challenge the conventional understanding of circadian rhythm complexity.
  • To propose a simplified model for biological oscillations.

Main Methods:

  • Theoretical modeling of a single activation-repression biochemical reaction pair.
  • Incorporation of spatially separated reaction sites.
  • Analysis of molecular transport mediated by diffusion.

Main Results:

  • A single activation-repression reaction pair with spatially separated sites is sufficient for sustained oscillations.
  • This simplified system generates oscillations without requiring multiple intermediate steps.
  • Diffusion-mediated molecular transport is key to the oscillatory behavior.

Conclusions:

  • The simplest configuration for biological oscillations involves spatially separated reactions and diffusion.
  • This finding provides a new conceptual basis for understanding biological clocks.
  • The model can inspire the design of minimal in vitro assays for constructing biological clocks.