Quantification of Molecular Interactions in Living Cells in Real Time using a Membrane Protein Nanopattern

• Published in: Analytical chemistry (Washington) Vol. 92; no. 13; pp. 8983 - 8991
• Main Authors: Reichmuth, Andreas Michael, Zimmermann, Mirjam, Wilhelm, Florian, Frutiger, Andreas, Blickenstorfer, Yves, Fattinger, Christof, Waldhoer, Maria, Vörös, János
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 07.07.2020
• Subjects: Arrestin - chemistry; Arrestin - genetics; Arrestin - metabolism; Assaying; Cells (biology); Chemistry; Fluorescence Resonance Energy Transfer - methods; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; HEK293 Cells; Humans; Membrane proteins; Membrane Proteins - chemistry; Membrane Proteins - genetics; Membrane Proteins - metabolism; Membranes; Mode of action; Molecular interactions; Optical measuring instruments; Protein Interaction Maps; Proteins; Real time; Receptors, Adrenergic, beta-2 - chemistry; Receptors, Adrenergic, beta-2 - genetics; Receptors, Adrenergic, beta-2 - metabolism; Toxicity
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/acs.analchem.0c00987

Molecular processes within cells have traditionally been studied with biochemical methods due to their high degree of specificity and ease of use. In recent years, cell-based assays have gained more and more popularity since they facilitate the extraction of mode of action, phenotypic, and toxicity information. However, to provide specificity, cellular assays rely heavily on biomolecular labels and tags while label-free cell-based assays only offer holistic information about a bulk property of the investigated cells. Here, we introduce a cell-based assay for protein–protein interaction analysis. We achieve specificity by spatially ordering a membrane protein of interest into a coherent pattern of fully functional membrane proteins on the surface of an optical sensor. Thereby, molecular interactions with the coherently ordered membrane proteins become visible in real time, while nonspecific interactions and holistic changes within the living cell remain invisible. Due to its unbiased nature, this new cell-based detection method presents itself as an invaluable tool for cell signaling research and drug discovery.