Fig. 1: Conformational landscape of prestin.

a Structural overview of the prestin homodimer, individual chains colored in grays or cyans to emphasize the domain-swapped dimer interface (left). Zoomed and rotated view of the transmembrane domain (TMD) from the extracellular side, dark and light cyan/gray indicate the Transport (TD) and Scaffold (SD) domains, respectively (PDBID: 7LGU). b Conformational landscape of prestin visualized by principal component analysis (PCA) of equilibrium MD simulations. Frequencies are shown as -RTln(δ), where δ is the normalized count in the two-dimensional PCA landscape. Experimental cryo-EM structures of prestin in various conformations projected onto the PCA landscape in colored circles (see legend). Compact (CS) and expanded (ES) state clusters identified via DBSCAN are shown in orange and green, respectively. Centroids were calculated for each cluster and are shown in black. c Centroids of the CS and ES clusters represented in cartoon, showing the TMD of a protomer. G82–S505 distance for each centroid is displayed, demonstrating expansion of the TMD. d Distributions of structural observables: transport-scaffold (TD-SD) rotation (left), TD-SD z-shift distance (center), and intracellular protein-occupied area in the membrane, i.e., excluded-lipid area (right). Detailed approach for the lipid-excluded area found in the methods. e Overlay of the transport domains (aligned by scaffold domain) of the two centroids. ES displays a downward shift of (1.5 Å), and clockwise turn of ~7°. Valine 139 shown as stick, other residues queried by SCAM/water-accessibility shown in gray. Structural context of analyses (inset). Source data are provided as a Source data file.