Inducible protein expression in stably transfected cells paves the way toward in-cell NMR studies in defined physiological states and 3D tissue cultures.

In-cell NMR spectroscopy is the sole technique for characterizing protein structure, dynamics, and interactions in living human cells at atomic resolution. However, its applications have been restricted to asynchronous single-cell suspensions. We developed a strategy based on target protein inducible overexpression in stably transfected cells, allowing the acquisition of high-resolution in-cell NMR spectra in physiologically defined cellular states and 3D tissue models.