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Phosphoinositides and PIPs

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Related Experiment Video

Updated: Jun 26, 2026

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

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

Published on: January 6, 2016

Phosphoinositide (PI) 3-kinase assays.

Michael J Fry¹

¹School of Biological Sciences, Division of Biomolecular Science, University of Reading, Whiteknights, Reading, Berkshire, UK. m.j.fry@reading.ac.uk

Methods in Molecular Biology (Clifton, N.J.)

|January 24, 2009

Summary

Identifying specific phosphoinositide 3-kinase (PI3K) isoforms involved in cellular processes is crucial. This study presents a robust in vitro PI3K assay to differentiate between PI3K classes and isoforms for accurate signaling pathway analysis.

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Published on: July 26, 2019

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Published on: October 15, 2016

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Last Updated: Jun 26, 2026

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

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

Published on: January 6, 2016

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

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

Published on: July 26, 2019

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Published on: October 15, 2016

Area of Science:

Cellular Biology
Biochemistry
Molecular Signaling

Background:

Phosphoinositide 3-kinase (PI3K) pathways regulate critical cellular functions like survival, growth, and motility.
The expanding PI3K family and related kinases, targeted by inhibitors like wortmannin and LY294002, necessitate refined identification methods.
Distinguishing between the eight PI3K members and related kinases is challenging in complex cellular signaling.

Purpose of the Study:

To develop and validate a reliable in vitro assay for PI3K activity.
To enable researchers to identify specific PI3K classes and isoforms in cellular processes.
To provide a tool for dissecting PI3K involvement in signaling pathways.

Main Methods:

Development of a robust in vitro phosphoinositide 3-kinase assay.
Adaptation of the assay for use with immunoprecipitates and purified proteins.
Modification of substrate and assay conditions to enhance specificity.

Main Results:

The described in vitro assay effectively measures PI3K activity.
Assay modifications allow for the differentiation of PI3K classes.
The assay facilitates the identification of specific PI3K isoforms involved in cellular signaling.

Conclusions:

This assay provides a valuable tool for researchers studying PI3K signaling.
Accurate identification of PI3K isoforms is essential for understanding normal and disease-related cellular processes.
The methodology aids in elucidating the specific roles of different PI3K family members.