We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Insights into receptor structure and dynamics at the surface of living cells.
- Authors
Steiert, Frederik; Schultz, Peter; Höfinger, Siegfried; Müller, Thomas D.; Schwille, Petra; Weidemann, Thomas
- Abstract
Evaluating protein structures in living cells remains a challenge. Here, we investigate Interleukin-4 receptor alpha (IL-4Rα) into which the non-canonical amino acid bicyclo[6.1.0]nonyne-lysine (BCNK) is incorporated by genetic code expansion. Bioorthogonal click labeling is performed with tetrazine-conjugated dyes. To quantify the reaction yield in situ, we develop brightness-calibrated ratiometric imaging, a protocol where fluorescent signals in confocal multi-color images are ascribed to local concentrations. Screening receptor mutants bearing BCNK in the extracellular domain uncovered site-specific variations of both click efficiency and Interleukin-4 binding affinity, indicating subtle well-defined structural perturbations. Molecular dynamics and continuum electrostatics calculations suggest solvent polarization to determine site-specific variations of BCNK reactivity. Strikingly, signatures of differential click efficiency, measured for IL-4Rα in ligand-bound and free form, mirror sub-angstrom deformations of the protein backbone at corresponding locations. Thus, click efficiency by itself represents a remarkably informative readout linked to protein structure and dynamics in the native plasma membrane. It is challenging to approach protein structures in living cells. Here the authors investigate Interleukin-4 receptor alpha, which has a noncanonical amino acid incorporated at different locations, and see that evaluating click efficiency with calibrated imaging gives information on structure-related properties.
- Subjects
SURFACE dynamics; GENETIC code; SURFACE structure; PROTEIN structure; MOLECULAR dynamics; CELL membranes
- Publication
Nature Communications, 2023, Vol 14, Issue 1, p1
- ISSN
2041-1723
- Publication type
Article
- DOI
10.1038/s41467-023-37284-4