Collagen-derived dipeptide prolyl hydroxyproline directly binds to Foxg1 to change its conformation and inhibit the interaction with Runx2

ABSTRACT

Collagen-derived dipeptide prolyl hydroxyproline (Pro-Hyp) is involved in the proliferation and differentiation of various types of cultured cells. To elucidate the mechanism underlying Pro-Hyp actions during osteoblast differentiation, we hypothesized that proteins binding to Pro-Hyp serve to mediate cellular signaling, affecting Runx2 expression. Recently, we performed the characterization of Foxg1, that it enhances Runx2 expression in the presence of Pro-Hyp. Our findings indicate that Pro-Hyp directly binds to the Foxg1 recombinant protein, which leads to the structural alteration of the Foxg1 protein. In addition, Foxg1 appears to interact with Runx2 in the absence of Pro-Hyp, with Pro-Hyp disrupting the interaction between Foxg1 and Runx2. Collectively, our results indicate that the Pro-Hyp bound Foxg1 alters the structured conformation of Foxg1, resulting in conformational changes that lead to dissociation from Runx2. These novel findings suggest that during osteoblast differentiation, Pro-Hyp mediates Runx2 activity though directly binding to Foxg1 and increases Runx2 expression.

Abbreviations: CPT: collagen peptide; GST: Glutathione S-transferase; PAGE: Polyacrylamide gel electrophoresis; PCR: Polymerase chain reaction; prolyl hydroxyproline: Pro-Hyp

Graphical abstract

Pro-Hyp bound Foxg1 appears to dissociate Runx2 from the Foxg1 complex.

KEYWORDS:

• Prolyl-hydroxyproline
• collagen-derived peptide
• Foxg1
• Runx2
• osteoblast

Acknowledgments

The authors wish to acknowledge Airplants Bio co Ltd for technical advice on experiments.

Author contribution

Conceptualization: YK, YO, AM and HM

Investigation: KN

supervision: JS and HM

Writing the original draft: KN

All authors reviewed and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.