: 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 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 initiates bone and cartilage development and is particularly critical for patterning teeth. Mutations in BMP4 are linked to tooth agenesis (missing teeth).

is a versatile secreted signaling molecule belonging to the TGF-beta superfamily . Known for its critical role in early development and tissue homeostasis, it acts as a "master controller" for cellular fate. Biological Structure & Mechanisms

: It drives the formation of the heart, lungs, kidneys, and limbs. In the heart, it is essential for atrio-ventricular septation .

: It primarily signals through two routes: