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bioRxiv · 10.1101/2024.07.02.600619

Poly(ADP-ribose) binding sites on collagen I fibrils for nucleating intrafibrillar bone mineral

Zecca, M. A.·Greer, H. F.·Duer, M. J.
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Abstract

Bone calcification is essential for vertebrate life. The mechanism by which mineral ions are transported into collagen fibrils to induce intrafibrillar mineral formation requires a calcium binding biopolymer that also has highly selective binding to the collagen fibril hole zones where intrafibrillar calcification begins, over other bone extracellular matrix components. Poly(ADP-ribose) has been shown to be a candidate biopolymer for this process and we show here that poly(ADP-ribose) has high affinity, highly conserved binding sites in the collagen type I C-terminal telopeptides. The discovery of these poly(ADP-ribose)-collagen binding sites gives new insights into the chemical mechanisms underlying bone calcification and possible mechanisms behind pathologies where there is dysfunctional bone calcification.

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Zecca, M. A., Greer, H. F., Duer, M. J.. 2024-07-04. Poly(ADP-ribose) binding sites on collagen I fibrils for nucleating intrafibrillar bone mineral. https://doi.org/10.1101/2024.07.02.600619

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