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

Positive and Negative Feedback Loops01:18

Positive and Negative Feedback Loops

25.2K
Animal organs and organ systems constantly adjust to internal and external changes through a process called homeostasis ("steady state"). Examples of these changes include regulation of the level of glucose or calcium in the blood or internal responses to external temperatures. Homeostasis requires  maintaining an internal dynamic equilibrium:
25.2K
Root Loci for Positive-Feedback Systems01:23

Root Loci for Positive-Feedback Systems

350
The Hartley oscillator is a positive feedback system that sustains oscillations by feeding the output back to the input in phase, thereby reinforcing the signal. Positive feedback systems can be viewed as negative feedback systems with inverted feedback signals. In these systems, the root locus encompasses all points on the s-plane where the angle of the system transfer function equals 360 degrees.
The construction rules for the root locus in positive feedback systems are similar to those in...
350
Feedback Inhibition00:46

Feedback Inhibition

57.1K
Biochemical reactions are occurring constantly in cells, converting starting substances to different products, usually with the help of enzymes that speed the reactions. Without enzymes, it would take far too long for most reactions to occur to be useful to the cell!
57.1K
Operational Amplifiers01:17

Operational Amplifiers

2.0K
The operational amplifier, often referred to as an op-amp, is a multifaceted building block of a circuit. This electronic component functions like a voltage-controlled voltage source and can also be used to create a voltage- or current-controlled current source. The design of an operational amplifier enables it to execute mathematical operations when external components like resistors and capacitors are linked to its terminals. An op-amp has the capacity to sum signals, amplify a signal,...
2.0K
MOSFET Amplifiers01:17

MOSFET Amplifiers

521
The MOSFET, when operating in its active region, functions as a voltage-controlled current source. In this region, the gate-to-source voltage controls the drain current. This principle underlies the operation of the transconductance MOSFET amplifier. The output current is directed through a load resistor to convert this amplifier into a voltage amplifier. The output voltage is then obtained by subtracting the voltage drop across the load resistance from the supply voltage. This process results...
521
BJT Amplifiers01:14

BJT Amplifiers

987
Bipolar Junction Transistors (BJTs) are pivotal components in amplifier circuits, functioning as voltage-controlled current sources in their active region. This characteristic allows them to efficiently control the collector current through variations in the base-emitter voltage. Essentially, BJTs amplify power due to their ability to take a weak input signal and output a much stronger signal.
In BJT amplifier configurations, particularly in common-emitter setups, the transistor's role...
987

You might also read

Related Articles

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

Sort by
Same author

Barbaloin Alleviates Lung Ischemia-Reperfusion Injury by Dual-Targeting IL-6 and PNP.

International journal of molecular sciences·2026
Same author

Mapping and engineering the human cell-cell interactome.

Nature biotechnology·2026
Same author

Programmable pathway profiles reveal signaling principles of TGF-β superfamily receptors.

bioRxiv : the preprint server for biology·2026
Same author

Cell-type resolved transcriptional network analysis of in vivo cellular senescence following injury.

PLoS computational biology·2026
Same author

Development of National Anticoagulation Guidelines for Pregnant Women with Mechanical Heart Valves in Rwanda.

Cardiovascular journal of Africa·2026
Same author

Staged Hybrid Treatment of a Large Aneurysmal Pulmonary Sequestration With Thoracic Endovascular Aortic Repair Followed by Lobectomy.

Annals of thoracic surgery short reports·2026
Same journal

Glycoform engineering of a mammalian platform to sculpt a humanized recombinant bioscavenger.

Cell systems·2026
Same journal

Targeted genomic editing of human gut Bacteroides species based on CRISPR-associated transposases.

Cell systems·2026
Same journal

Scalable enumeration and sampling of minimal metabolic pathways for organisms and communities.

Cell systems·2026
Same journal

Deciphering protein mutation-phenotype linkages from CRISPR-based tiling mutagenesis screens.

Cell systems·2026
Same journal

High-throughput machine learning-aided antibody discovery for cell surface antigens.

Cell systems·2026
Same journal

Quantitative cytokine profiling of primary human macrophages reveals distinct single-cell modes of trained immunity.

Cell systems·2026
See all related articles

Related Experiment Video

Updated: Feb 4, 2026

Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

8.2K

Self-Amplifying Pulsatile Protein Dynamics without Positive Feedback.

Rosa Martinez-Corral1, Elba Raimundez2, Yihan Lin3

  • 1Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park (PRBB), Dr. Aiguader 88, Barcelona 08003, Spain.

Cell Systems
|October 15, 2018
PubMed
Summary
This summary is machine-generated.

Irregular protein activity pulses can arise from negative feedback alone, not requiring positive feedback. This study demonstrates a general mechanism for stochastic pulse generation using the protein kinase A system.

Keywords:
biological noisecell signaling dynamicscellular oscillationsfeedbackprotein activationprotein activity pulsesultrasensitivity

More Related Videos

Characterization of the Isolated, Ventilated, and Instrumented Mouse Lung Perfused with Pulsatile Flow
10:02

Characterization of the Isolated, Ventilated, and Instrumented Mouse Lung Perfused with Pulsatile Flow

Published on: April 29, 2011

16.9K
Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor
11:22

Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor

Published on: June 14, 2011

17.7K

Related Experiment Videos

Last Updated: Feb 4, 2026

Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

8.2K
Characterization of the Isolated, Ventilated, and Instrumented Mouse Lung Perfused with Pulsatile Flow
10:02

Characterization of the Isolated, Ventilated, and Instrumented Mouse Lung Perfused with Pulsatile Flow

Published on: April 29, 2011

16.9K
Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor
11:22

Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor

Published on: June 14, 2011

17.7K

Area of Science:

  • Biochemistry and Molecular Biology
  • Systems Biology
  • Cellular Dynamics

Background:

  • Many proteins display dynamic activation patterns as irregular pulses.
  • These pulses are often linked to positive and negative feedback loops in regulatory networks.
  • Positive feedback mechanisms are challenging to prove definitively, prompting investigation into negative feedback-only models.

Purpose of the Study:

  • To investigate if stochastic protein activity pulses can be generated solely by negative feedback loops.
  • To explore the underlying mechanisms of pulse generation in biological systems.
  • To use the protein kinase A (PKA) system as a model to understand pulsatile protein activity.

Main Methods:

  • Utilized the protein kinase A (PKA) system, a regulator of the yeast Msn2 transcription factor.
  • Simplified the regulatory network to a two-variable model.
  • Analyzed the contribution of zero-order ultrasensitivity, timescale separation, and feedback delay to pulse generation.

Main Results:

  • Demonstrated that irregular protein activity pulses can emerge from a negative feedback loop exclusively.
  • Identified a combination of zero-order ultrasensitivity, timescale separation, and effective delay as sufficient for pulse amplification.
  • Showed that the identified circuit topology can explain both activation and inactivation pulses.

Conclusions:

  • Negative feedback loops alone are capable of generating stochastic protein activity pulses.
  • A general mechanism for stochastic pulse generation exists, involving ultrasensitivity, timescale separation, and feedback delay.
  • The findings offer insights into the regulation of pulsatile biological processes.