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

Phosphoinositides and PIPs01:42

Phosphoinositides and PIPs

10.5K
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
10.5K
PI3K/mTOR/AKT Signaling Pathway01:22

PI3K/mTOR/AKT Signaling Pathway

6.1K
The mammalian target of rapamycin  (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1  (mTORC1) and mTOR complex 2  (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast,  mTORC2 consists of a...
6.1K
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

13.6K
Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
13.6K
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

6.1K
The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
6.1K
Sexually Transmitted Infections01:26

Sexually Transmitted Infections

1.5K
Sexually transmitted infections (STIs) are diseases transmitted primarily through unsafe sexual interactions. Bacteria, viruses, or parasites cause them and can result in severe health complications if untreated.ChlamydiaThe bacterium Chlamydia trachomatis is responsible for the disease Chlamydia, the most common STI in the United States. This peculiar pathogen requires human cells to reproduce, residing intracellularly. The initial infection often goes unnoticed because it typically does not...
1.5K

You might also read

Related Articles

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

Sort by
Same author

Tirzepatide Regulates Pacemaker Function by Modulating cAMP and Calcium Dynamics in Human Sinoatrial Node Cells.

Circulation·2026
Same author

Publisher Correction: Rethinking medical education through systems biology to address complexity.

NPJ systems biology and applications·2026
Same author

Syk activation during FcγR-mediated phagocytosis involves Syk palmitoylation and desulfenylation.

Life science alliance·2026
Same author

Profiling Immune-Independent Response to Immune Checkpoint Inhibitors on Stem Cell-Derived Cardiomyocytes, Organoids, and Mouse Models.

Circulation·2026
Same author

Rethinking medical education through systems biology to address complexity.

NPJ systems biology and applications·2026
Same author

SPARC: a structural pathogenicity algorithm for risk classification of hERG variants.

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology·2025

Related Experiment Video

Updated: Mar 15, 2026

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function
09:26

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function

Published on: October 15, 2013

14.6K

HIV-Tat induces a decrease in IKr and IKsvia reduction in phosphatidylinositol-(4,5)-bisphosphate availability.

Zeineb Es-Salah-Lamoureux1, Mariam Jouni1, Olfat A Malak1

  • 1l'institut du thorax, Inserm, CNRS, Université de Nantes, Nantes, France.

Journal of Molecular and Cellular Cardiology
|September 4, 2016
PubMed
Summary

HIV-associated QT prolongation may stem from the viral Tat protein. Tat protein reduces crucial cardiac potassium currents (IKr and IKs) by sequestering PIP2, impacting heart repolarization in HIV patients.

Keywords:
HIV-Tat proteinI(Kr)I(Ks)Induced pluripotent stem cell-derived cardiomyocytesLong QT syndromePhosphatidylinositol-(4,5)-bisphosphate

More Related Videos

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
08:07

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry

Published on: July 26, 2019

9.0K
A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
11:44

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3

Published on: January 24, 2016

12.6K

Related Experiment Videos

Last Updated: Mar 15, 2026

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function
09:26

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function

Published on: October 15, 2013

14.6K
Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
08:07

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry

Published on: July 26, 2019

9.0K
A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3
11:44

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3

Published on: January 24, 2016

12.6K

Area of Science:

  • Cardiology
  • Molecular Biology
  • Virology

Background:

  • Patients with HIV exhibit increased QT prolongation, a cardiac arrhythmia.
  • The molecular mechanisms underlying this phenomenon remain unclear.
  • The HIV protein Tat is secreted and can affect cardiac function.

Purpose of the Study:

  • To investigate the molecular basis of Tat protein's effect on cardiac repolarization.
  • To determine if HIV Tat protein impacts human cardiac ion channels.
  • To elucidate the mechanism of Tat-induced QT prolongation.

Main Methods:

  • Transfection of Tat protein in heterologous expression systems.
  • Electrophysiological recordings of hERG (IKr) and KCNE1-KCNQ1 (IKs) channels.
  • Incubation of human induced pluripotent stem cells-derived cardiomyocytes with Tat protein.
  • Assessment of action potential duration and alternans.

Main Results:

  • Tat transfection reduced hERG (IKr) and KCNE1-KCNQ1 (IKs) currents and accelerated their deactivation.
  • These effects were linked to phosphatidylinositol-(4,5)-bisphosphate (PIP2) binding.
  • Tat incubation in human cardiomyocytes prolonged action potential duration and induced AP alternans.

Conclusions:

  • HIV Tat protein sequesters PIP2, reducing cardiac IKr and IKs currents.
  • This mechanism provides a molecular explanation for QT prolongation in HIV-infected patients.
  • Tat's impact on cardiac ion channels highlights a potential therapeutic target.