The ligand trap binds the ligand BMP2, blocking BMP signalling
Formation of a heteromeric BMP receptor complex
BMP2 binds to the receptor complex
Type II receptor phosphorylates type I receptor
An anchoring protein, Endofin, recruits R-Smad1/5/8
I-Smad binds to type I receptor, preventing Smad1/5/8 from being activated
Activated type I receptor phosphorylates R-Smad1/5/8 directly
Phospho-R-Smad1/5/8 dissociates from the receptor complex
I-Smad competes with Co-Smad for R-Smad1/5/8
Phospho-R-Smad1/5/8 forms a complex with Co-Smad
The phospho-R-Smad1/5/8:Co-Smad transfers to the nucleus
SKI complexes with the Smad complex, suppressing BMP2 signalling
I-Smad competes with R-Smad1/5/8 for type I receptor
Ubiquitin-dependent degradation controls basal levels of R-Smad1/5/8
Ubiquitin-dependent degradation of the Smad complex terminates BMP2 signalling
Signaling by BMP