Arg-Tyr cation-π interactions drive phase separation and β-sheet assembly in native spider dragline silk.

ABSTRACT: Liquid-liquid phase separation (LLPS) is a fundamental principle of protein organization in intrinsically disordered proteins (IDPs) and biomaterials, yet the residue-level interactions that link condensation to structural ordering remain poorly defined. In spider dragline silk, LLPS is believed to initiate the transition from soluble spidroin dope into β-sheet-rich fibers that provide exceptional toughness, yet how sequence-specific motifs govern this process has been unclear. Here, we combine isotope-edited solution NMR, dynamic nuclear polarization (DNP)-enhanced solid-state NMR, molecular dynamics simulations, and AlphaFold3 modeling to define the molecular role of arginine and tyrosine in Latrodectus hesperus dragline silk. Phosphate triggers LLPS while preserving intrinsic dis

SUBMITTER: Johnson HR 

PROVIDER: S-EPMC12772222 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature