A Bone Morphogenetic Protein (BMP)-derived Peptide Based on the Type I Receptor-binding Site Modifies Cell-type Dependent BMP Signalling

Zhen Tong,Jingxu Guo,Robert C. Glen,Nicholas W. Morrell,Wei Li

doi:10.1038/s41598-019-49758-x

Zhen Tong, Jingxu Guo + Show 3 more

Open Access

https://doi.org/10.1038/s41598-019-49758-x

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Abstract

Bone morphogenetic proteins (BMPs) are multifunctional cytokines of the transforming growth factor β (TGFβ) superfamily with potential therapeutic applications due to their broad biological functionality. Designing BMP mimetics with specific activity will contribute to the translational potential of BMP-based therapies. Here, we report a BMP9 peptide mimetic, P3, designed from the type I receptor binding site, which showed millimolar binding affinities for the type I receptor activin receptor like kinase 1 (ALK1), ALK2 and ALK3. Although showing no baseline activity, P3 significantly enhanced BMP9-induced Smad1/5 phosphorylation as well as ID1, BMPR2, HEY1 and HEY2 gene expression in pulmonary artery endothelial cells (hPAECs), and this activity is dependent on its alpha helix propensity. However, in human dermal microvascular endothelial cells, P3 did not affect BMP9-induced Smad1/5 phosphorylation, but potently inhibited ALK3-dependent BMP4-induced Smad1/5 phosphorylation and gene expression. In C2C12 mouse myoblast cells, P3 had no effect on BMP9-induced osteogenic signalling, which is primarily mediated by ALK2. Interestingly, a previously published peptide from the knuckle region of BMP9 was found to inhibit BMP4-induced Smad1/5 phosphorylation. Together, our data identify a BMP9-derived peptide that can selectively enhance ALK1-mediated BMP9 signalling in hPAECs and modulate BMP9 and BMP4 signalling in a cell type-specific manner.

Highlights

Bone morphogenetic proteins (BMPs) are homo-dimers, functioning through serine/threonine kinase receptors, forming signalling complexes with two copies of type I receptors (activin receptor-like kinase 1 (ALK1), ALK2 and ALK3) via www.nature.com/scientificreports/
We describe the design and characterisation of a novel BMP9-mimetic peptide from the activin receptor like kinase 1 (ALK1)-binding surface that can enhance BMP9-induced Smad1/5 phosphorylation in human pulmonary artery endothelial cells, while inhibit BMP4-induced Smad1/5 phosphorylation in human dermal microvascular endothelial cells (HMEC-1)
Peptides P1*, P2*, P3* and P3 (* indicates biotinylation at the N-terminus) were designed from the ALK1-binding site of BMP9 or BMP10 based on the crystal structure of the ALK1:BMP9:ActRIIb complex[8] (Fig. 1B)

Summary

Introduction

BMPs are homo-dimers, functioning through serine/threonine kinase receptors, forming signalling complexes with two copies of type I receptors (activin receptor-like kinase 1 (ALK1), ALK2 and ALK3) via www.nature.com/scientificreports/. The BMP9 peptide from the ALK1-binding surface enhances BMP9-induced Smad1/5 phosphorylation in hPAECs. In order to understand how the interaction between peptide P3 and ALK1 allows the stimulation of BMP9-induced pSmad1/5 signalling, we generated several control peptides to test alongside P3 (Fig. 3A).

Results

Conclusion