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Updated: Jul 4, 2026

Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET
Published on: August 17, 2022
Crystal structure of human ERp44 shows a dynamic functional modulation by its carboxy-terminal tail
Likun Wang1, Lei Wang, Stefano Vavassori
1National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
Abstract:
ERp44 mediates thiol-dependent retention in the early secretory pathway, forming mixed disulphides with substrate proteins through its conserved CRFS motif. Here, we present its crystal structure at a resolution of 2.6 A. Three thioredoxin domains-a, b and b'-are arranged in a clover-like structure. A flexible carboxy-terminal tail turns back to the b' and a domains, shielding a hydrophobic pocket in domain b' and a hydrophobic patch around the CRFS motif in domain a. Mutational and functional studies indicate that the C-terminal tail gates the CRFS area and the adjacent hydrophobic pocket, dynamically regulating protein quality control.
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