Related Experiment Video

Updated: Aug 11, 2026

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
10:52

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation

Published on: January 6, 2016

Phosphoinositides in FCgamma receptor signaling

James W Booth1

  • 1Department of Immunology, University of Toronto, Molecular and Cellular Biology Research, Sunnybrook and Women's Research Institute, Toronto, Ontario, M4N 3M5, Canada. James.Booth@sw.ca

Frontiers in Bioscience : a Journal and Virtual Library
|December 22, 2005
PubMed

Insights

Fc gamma receptors (FcγRs) trigger immune responses to IgG complexes, largely controlled by phosphoinositides like phosphatidylinositol (4,5)P2 and (3,4,5)P3. This study explores downstream effectors and signaling pathways linking FcγRs to phosphoinositide metabolism.

Area of Science:

  • Immunology
  • Cell Signaling
  • Molecular Biology

Background:

  • Fc gamma receptors (FcγRs) are critical mediators of immune responses involving immunoglobulin G (IgG) complexes.
  • Phosphoinositides, particularly phosphatidylinositol (4,5)P2 and phosphatidylinositol (3,4,5)P3, play a regulatory role in FcγR-mediated cellular functions.

Purpose of the Study:

  • To elucidate the role of phosphoinositides in FcγR signaling.
  • To identify downstream effectors and signaling pathway components involved in FcγR activation.

Main Methods:

  • Review and discussion of existing literature on FcγR signaling pathways.
  • Analysis of phosphoinositide metabolism in the context of FcγR-mediated immune responses.

Main Results:

  • FcγR-mediated immune responses are extensively regulated by specific phosphoinositides.
  • Key downstream signaling molecules and pathways coupling FcγRs to phosphoinositide metabolism have been identified.

Conclusions:

  • Phosphoinositides are central regulators of FcγR function.
  • Understanding these signaling pathways is crucial for comprehending immune complex recognition and response.

More Related Videos

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions10:58

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions

Published on: July 27, 2017

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry08:07

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

Published on: July 26, 2019

Related Concept Videos

What are Second Messengers?01:12

What are Second Messengers?

Because many receptor binding ligands are hydrophilic, they do not cross the cell membrane and thus their message must be relayed to a second messenger on the inside. There are several second messenger pathways, each with their own way of relaying information. G-protein coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol path is active when the receptor induces phospholipase C to hydrolyze the phospholipid,...
Phosphoinositides and PIPs01:42

Phosphoinositides and PIPs

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...
Amplifying Signals via Second Messengers01:15

Amplifying Signals via Second Messengers

Many receptor binding ligands are hydrophilic; they do not cross the cell membrane but bind to cell-surface receptors. Thus, their message must be relayed by second messengers present in the cell cytoplasm. There are several second messenger pathways, each with its own way of relaying information. For example, the G protein-coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol pathway is active when the receptor induces...
Amplifying Signals via Enzymatic Cascade01:22

Amplifying Signals via Enzymatic Cascade

When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
IP3/DAG Signaling Pathway01:11

IP3/DAG Signaling Pathway

Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the  phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and produces two-second...
Intracellular Signaling Affects Focal Adhesions01:17

Intracellular Signaling Affects Focal Adhesions

Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...