Related Experiment Video
Updated: Jan 31, 2026

Fluorescence Anisotropy as a Tool to Study Protein-protein Interactions
Published on: October 21, 2016
Synthetic phosphopeptides: From spike-in standards to affinity tools for protein-protein interaction studies
Martin Winter1, Ramona Mayer2, Uwe Warnken2
1Functional Proteome Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120, Heidelberg, Germany; Translational Radiation Oncology, National Center for Tumor Diseases (NCT), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 460, D-69120, Heidelberg, Germany; German Cancer Consortium (DKTK), Heidelberg, Germany.
Abstract:
Synthetic isotope labeled phosphopeptides are valuable tools for the quantification and validation of phosphoproteome data. Here, we report that the same set of phosphopeptides, which are used as spike-in standards, can be successfully applied for identification of stimulus specific protein-protein interactions mediated by the respective phosphorylation sites. As a proof-of-concept, binding of two γH2AX (pS139) phosphosite specific interaction partners, MDC1 and 53BP1, was confirmed and elevated binding affinity was revealed in response to ionizing radiation. Our strategy is generally applicable and enables multiplexed validation and functional analysis of phosphorylation sites offering great potential for the follow-up of phosphoproteome studies.
Related Concept Videos
Protein Networks
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
Protein-protein Interfaces
Protein and Protein Structure
A protein's shape is critical to its function. For example, an enzyme...
Affinity and Avidity
What are Proteins?
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...

