: Binding to Type I (ALK3/ALK6) and Type II (BMPR2) receptors triggers the phosphorylation of R-Smads (Smad1/5/8) , which complex with Smad4 and move into the nucleus to regulate gene expression.
: It can also directly activate pathways like ERK, p38 MAPK, and JNK to regulate migration and survival. : Binding to Type I (ALK3/ALK6) and Type
: Factors like Noggin, Chordin, and Gremlin act as "ligand traps," preventing BMP4 from binding to its receptors. This balance is vital for correct organ patterning. Key Functions in Development This balance is vital for correct organ patterning
BMP4 is essential from the earliest stages of life, where its loss often leads to embryonic lethality. In the heart, it is essential for atrio-ventricular
: It drives the formation of the heart, lungs, kidneys, and limbs. In the heart, it is essential for atrio-ventricular septation .
Beyond development, BMP4 is a major player in adult metabolism and disease.
: It typically suppresses "default" neural differentiation to promote skin formation; however, in the adult brain, it helps maintain neural stem cell pools. Metabolic & Clinical Significance