In Xenopus, the bone morphogenetic protein (BMP) activity gradient is defined by a 'shuttling-based' mechanism, whereby the BMP ligands are translocated ventrally through their association with the BMP inhibitor Chordin. This shuttling, with feedback repression of the BMP ligand Admp, offers a quantitative explanation to earlier observations, and accounts naturally for the scaling of embryo pattern with its size.
- Danny Ben-Zvi
- Ben-Zion Shilo
- Naama Barkai
