Related Experiment Video
Updated: Jan 20, 2026
08:32
Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
Published on: March 2, 2014
10.9K
PtdIns(3,5)P 2 Is an Endogenous Ligand of STING in Innate Immune Signaling
Biorxiv : the Preprint Server for Biology
|January 19, 2026
Summary
Phosphatidylinositol 3,5-bisphosphate [PtdIns(3,5)P2] acts as an endogenous ligand for STING, enhancing cGAMP-induced activation. This lipid molecule is crucial for STING trafficking and innate immune responses.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Cytosolic DNA triggers innate immunity via cGAS-STING pathway.
- STING, an ER-localized adaptor, activates TBK1 and IKK upon cGAMP binding.
- STING trafficking from ER to Golgi is essential for downstream signaling.
Purpose of the Study:
- To identify endogenous ligands of STING.
- To elucidate the role of PtdIns(3,5)P2 in STING activation and innate immunity.
Main Methods:
- Proteomics to identify STING-interacting proteins.
- CRISPR-mediated deletion of PIKfyve.
- In vitro biochemical assays including FRET and cryo-EM.
- Site-directed mutagenesis of STING.
Main Results:
- PtdIns(3,5)P2 identified as an endogenous ligand for STING.
- PIKfyve, a PtdIns(3,5)P2-producing enzyme, interacts with STING.
- PtdIns(3,5)P2 enhances cGAMP-induced STING activation and oligomerization.
- PIKfyve deletion or STING mutation blocks STING trafficking and TBK1 activation.
Conclusions:
- PtdIns(3,5)P2 is a critical lipid ligand for STING.
- PtdIns(3,5)P2 plays an essential role in STING-mediated innate immune signaling.
Related Concept Videos
08:32Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
10.9K
We describe a protocol to measure the antiviral cytokine production in mice infected with a model herpesvirus, murine gamma herpesvirus 68 (γHV68) that is closely-related to human Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV). Utilizing genetically modified mouse strains and mouse embryonic fibroblasts (MEFs), we assessed the antiviral cytokine production both in vivo and ex vivo. “Reconstituting” the expression of innate immune components in...
10.9K
09:09Removal and Replacement of Endogenous Ligands from Lipid-Bound Proteins and Allergens
3.3K
This protocol describes the removal of endogenous lipids from allergens, and their replacement with user-specified ligands through reverse-phase HPLC coupled with thermal annealing. 31P-NMR and circular dichroism allow for the rapid confirmation of ligand removal/loading, and the recovery of native allergen...
3.3K
12:47Using RNA-interference to Investigate the Innate Immune Response in Mouse Macrophages
12.1K
In this protocol, we describe methods to efficiently transfect murine macrophage cell lines with siRNAs using the Amaxa Nucleofector 96-well Shuttle System, stimulate the macrophages with lipopolysaccharide, and monitor the effects on inflammatory cytokine...
12.1K
01:21Introduction to Innate and Adaptive Immunity
8.9K
The human immune system is a complex defense mechanism that protects the body from harmful pathogens and foreign substances. It comprises two crucial components: innate and adaptive immunity.
Innate immunity is the body's natural, nonspecific defense system that acts quickly to protect against pathogens. It incorporates physical barriers like skin and mucous membranes and cellular elements such as phagocytes and natural killer cells. This part of our immune system provides an immediate,...
Innate immunity is the body's natural, nonspecific defense system that acts quickly to protect against pathogens. It incorporates physical barriers like skin and mucous membranes and cellular elements such as phagocytes and natural killer cells. This part of our immune system provides an immediate,...
8.9K
01:28Cells of the Innate Immune Response
8.7K
The innate immune response is an immediate and non-specific response against pathogens, acting swiftly to prevent the spread of infections. The primary cells involved in this response are phagocytes and natural killer (NK) cells.
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
8.7K
10:23Evaluation of Caspase Activation to Assess Innate Immune Cell Death
3.8K
This protocol describes a comprehensive method for assessing caspase activation (caspase-1, caspase-3, caspase-7, caspase-8, caspase-9, and caspase-11) in response to both in vitro and in vivo (in mice) models of infection, sterile insults, and cancer to determine the initiation of cell death pathways, such as pyroptosis, apoptosis, necroptosis, and...
3.8K