The function and activity of a protein are often modulated by other proteins with which it interacts. Characterizing protein–protein interactions is critical to understand protein function and the biology of the cell. Quantitative affinity purification followed by mass spectrometry is a powerful approach to investigate physical interaction partners of a protein of interest. Recent advances in technology now enable a quantification of up to 100 interactomes per day.
GFP-Traps® (ChromoTek GmbH) are ideal for efficient, one-step isolation of fluorescent fusion proteins and their interacting partners. In combination with the in-StageTip (iST) Sample Preparation Kit (PreOmics GmbH) both ensure an ideal sample preparation with high reproducibility and efficiency. The GFP-Trap® is a monovalent matrix with GFP-binding proteins coupled to it. They are suited for efficient, one-step isolation of fluorescent fusion proteins and their interacting partners. The GFP-Traps® are available either coupled to agarose beads or magnetic beads. The in-StageTip method is able to perform sample processing, from cell lysis through elution of purified peptides, in a single, enclosed volume. This robust and scalable method largely eliminates contamination or loss.1