Smad6-mediated inhibition of BMP/TGF-β signaling disrupts midbrain growth in chick embryos
This study demonstrates that while BMP4 overactivation does not affect midbrain development, the intracellular inhibitor SMAD6 significantly reduces dorsal midbrain growth in chick embryos by decreasing cell proliferation, highlighting the critical role of SMAD-dependent signaling in this process.