Atomistic Insights into TRPC6–Caveolin-1 Interactions Interface via All-Atom Molecular Dynamics Simulations: Structural and Energetic Basis for Selective Modulation

Abstract

The molecular determinants governing TRPC6 stabilization and its interaction with caveolin-1 (CAV1) remain poorly defined, despite their critical role in caveolae organization and signaling. The absence of atomistic structural models has hindered a mechanistic understanding of how TRPC6 is recruited to, and stabilized within, caveolar microdomains. Here, we combine all-atom molecular dynamics simulations with MM/PBSA calculations to characterize the TRPC6–CAV1 complex at atomic resolution. To preserve a biologically realistic membrane environment, harmonic restraints were applied to transmembrane and membrane-embedded regions of both proteins, while the cytosolic TRPC6 N-terminus and solvent-exposed edges of the CAV1 scaffolding domain were kept fully flexible, allowing the putative caveolin-binding motif to explore conformational space and form dynamic contacts. This protocol maintained overall structural integrity while capturing physiologically relevant flexibility at the interaction surface. MM/PBSA analysis revealed a highly favorable binding free energy (ΔG_binding = −255.9 ± 1.6 kJ/mol), dominated by electrostatic contributions and reinforced by hydrophobic and aromatic interactions. Per-residue energy decomposition identified an acidic patch in TRPC6 (residues 30–41) that engages a complementary basic, amphipathic segment in CAV1 (residues 85–106), defining a cooperative, reversible binding interface. These findings provide the first atomistic description of TRPC6 recruitment by CAV1 and establish a quantitative framework for the rational design of strategies to selectively modulate this interaction. Highlight Established the first atomistic model of the TRPC6–CAV1 interaction in caveolae Combined all-atom MD simulations with restrained membrane-embedded protein models Interface analysis shows reversible noncovalent binding via transient H-bonds and salt bridges MM/PBSA revealed strong electrostatic-driven binding of the TRPC6–CAV1 complex Identified an acidic TRPC6 N-terminal hotspot engaging a basic amphipathic CAV1 region Graphical Abstract