Related Experiment Video

Updated: Feb 5, 2026

Characterization of MLKL-mediated Plasma Membrane Rupture in Necroptosis
08:55

Characterization of MLKL-mediated Plasma Membrane Rupture in Necroptosis

Published on: August 7, 2018

11.3K

The pseudokinase MLKL activates PAD4-dependent NET formation in necroptotic neutrophils

Akshay A D'Cruz1,2, Mary Speir1,2, Meghan Bliss-Moreau1,2

  • 1Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA.

Science Signaling
|September 6, 2018
PubMed

Insights

Neutrophil extracellular trap (NET) formation involves the necroptotic effector mixed lineage kinase domain-like (MLKL) and receptor-interacting protein kinase-1 (RIPK1), leading to histone hypercitrullination and NET release for controlling MRSA infection.

Area of Science:

  • Immunology
  • Cell Biology
  • Microbiology

Background:

  • Neutrophil extracellular traps (NETs) are crucial for host defense but their formation mechanisms are not fully elucidated.
  • NETosis, the process of NET formation, involves cell death and the release of antimicrobial components.
  • Understanding the signaling pathways regulating NETosis is vital for developing new antimicrobial strategies.

Purpose of the Study:

  • To elucidate the molecular mechanisms and signaling pathways governing NET formation and release.
  • To identify key proteins involved in NETosis and their roles in neutrophil cell death.
  • To investigate the contribution of NETs to the control of methicillin-resistant Staphylococcus aureus (MRSA) infection.

Main Methods:

  • Utilized mouse and human neutrophils.
  • Investigated the roles of mixed lineage kinase domain-like (MLKL), receptor-interacting protein kinase-1 (RIPK1), RIPK3, and peptidylarginine deiminase 4 (PAD4) in NET formation.
  • Assessed NET extrusion, cell death pathways (apoptosis and necroptosis), reactive oxygen species (ROS) production, and histone modifications.
  • Examined the impact of genetic deficiencies in key proteins on NET formation and MRSA control.

Main Results:

  • Demonstrated that MLKL translocates to the plasma membrane, triggering ROS production and NET extrusion.
  • Showed that RIPK1 coordinates both caspase-8-dependent apoptosis and RIPK3/MLKL-dependent necroptosis in neutrophils.
  • Confirmed that PAD4 activation downstream of RIPK1/RIPK3/MLKL is essential for histone hypercitrination and NET release.
  • Found that genetic deficiency of RIPK3 and MLKL impaired NET formation but not cell death due to residual caspase-8 activity.
  • Highlighted the role of PAD4-dependent NET release in controlling MRSA infection.

Conclusions:

  • Identified a distinct signaling network involving RIPK1, RIPK3, MLKL, and PAD4 that regulates NET formation.
  • Established that PAD4-dependent NET release is crucial for controlling MRSA infection.
  • Provided insights into the interplay between cell death pathways and NETosis in innate immunity.

More Related Videos

Tyramide Signal Amplification for the Immunofluorescent Staining of ZBP1-Dependent Phosphorylation of RIPK3 and MLKL After HSV-1 Infection in Human Cells09:15

Tyramide Signal Amplification for the Immunofluorescent Staining of ZBP1-Dependent Phosphorylation of RIPK3 and MLKL After HSV-1 Infection in Human Cells

Published on: October 20, 2022

2.8K
Methods to Study Lipid Alterations in Neutrophils and the Subsequent Formation of Neutrophil Extracellular Traps10:58

Methods to Study Lipid Alterations in Neutrophils and the Subsequent Formation of Neutrophil Extracellular Traps

Published on: March 29, 2017

10.0K

Related Concept Videos

Solution Formation02:16

Solution Formation

There is no one solvent that can dissolve every type of solute. Some substances that readily dissolve in a certain solvent might be insoluble in a different solvent. A simple way to predict which substances dissolve in which solvent is the phrase "like dissolves like". This means that polar substances, such as salt and sugar, dissolve in a polar substance like water. In contrast, non-polar substances are more soluble in non-polar solvents such as carbon tetrachloride.
This selective...
37.8K
Frequency-dependent Selection01:21

Frequency-dependent Selection

When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.
24.1K
Temperature Dependence on Reaction Rate02:55

Temperature Dependence on Reaction Rate

The Collision Theory
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
89.1K
Drug Dependence01:17

Drug Dependence

Medications are typically administered to achieve therapeutic effects. Some drugs can modify an individual's mood and perception, frequently resulting in various enjoyable experiences. However, this can result in drug dependency, a condition marked by continuous drug use despite potential negative consequences. Drug dependency primarily falls into two categories: psychological and physical dependence. Psychological dependence occurs when the pleasurable feelings induced by the drug...
1.7K
Contact-dependent Signaling01:19

Contact-dependent Signaling

Contact-dependent signaling, as the name suggests, requires that communicating cells be in direct contact with each other. This is achieved either through receptor-ligand interactions or by specialized cytoplasmic channels that allow the flow of small molecules between cells. In animal cells, channels called gap junctions facilitate contact-dependent signaling in certain tissues, whereas, plasmodesmata perform a similar function in plants.
Gap Junctions
In animal cells, gap junctions are formed...
47.5K
Formation of Species01:31

Formation of Species

Speciation describes the formation of one or more new species from one or sometimes multiple original species. The resulting species are discrete from the parent species, and barriers to reproduction will typically exist. There are two primary mechanisms, speciation with and without geographic isolation—allopatric and sympatric speciation, respectively.
45.3K