Related Experiment Video
Updated: Jul 7, 2025

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity
Published on: January 5, 2016
In Vitro Phosphatase Assays for the Eya2 Tyrosine Phosphatase
Christopher Alderman1, Aaron Krueger1,2, John Rossi1
1Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
None:
Protein tyrosine phosphatases (PTP), such as the Eyes Absent (Eya) family of proteins, play important roles in diverse biological processes. In vitro phosphatase assays are essential tools for characterizing the enzymatic activity as well as discovering inhibitors and regulators of these phosphatases. Two common types of in vitro phosphatase assays use either a small molecule substrate that produces a fluorescent or colored product, or a peptide substrate that produces a colorimetric product in a malachite green assay. In this chapter, we describe detailed protocols of a phosphatase assay using small molecule 3-O-methylfluorescein phosphate (OMFP) as a substrate and a malachite green assay using the pH2AX peptide as a substrate to evaluate the phosphatase activity of EYA2 and the effect of small molecule inhibitors of EYA2. These protocols can be easily adapted to study other protein tyrosine phosphatases.

