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bioRxiv · 10.1101/2025.08.25.672158

Lysyl oxidase-mediated intermolecular crosslinks fine-tune collagen I molecular dynamics and regulate cell-matrix interactions through focal adhesions

Dillon, S.·Clark, J.·Duer, M. J.
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Abstract

Lysyl oxidase (LOX)-mediated intermolecular crosslinking is essential for collagen I fibril stability, yet its influence on collagen molecular conformation and dynamics, and the downstream consequences for cell-matrix interactions remain poorly understood. Here, we genetically modulated LOX in collagen I-producing MC3T3-E1 cells to generate matrices with elevated (overexpression, OX) or absent (knockout, KO) crosslinking. Enhanced crosslinking yielded thick, continuous, aligned fibrils, whereas reduced crosslinking produced friable, dissociated fibrils. Solid-state nuclear magnetic resonance spectroscopy (SSNMR) revealed local triple-helix unfolding and altered nanosecond- and microsecond-scale molecular motions in both OX and KO matrices, changes largely reversible upon decellularization, implicating a synergistic role of crosslinking chemistry and cell-applied forces in regulating the dynamically-accessible conformations of collagen I. Changes in the molecular structure and dynamics of collagen had a functional impact on cell adhesion and mechanotransduction. These findings identify collagen crosslinking as a tunable element of the extracellular matrix "mechanical code," integrating biochemical modification with molecular-scale mechanics to regulate cell-matrix adhesion and mechanosignalling.

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Dillon, S., Clark, J., Duer, M. J.. 2025-08-29. Lysyl oxidase-mediated intermolecular crosslinks fine-tune collagen I molecular dynamics and regulate cell-matrix interactions through focal adhesions. https://doi.org/10.1101/2025.08.25.672158

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