Ligand recognition and homophilic interactions in Tyro3: structural insights into the Axl/Tyro3 receptor tyrosine kinase family.

The receptor Tyro3 together with Axl and Mer form the Axl/Tyro3 family of receptor tyrosine kinases. Members of this family play essential roles in spermatogenesis, immunoregulation, and phagocytosis. Gas6, the product of growth arrest-specific gene, activates the kinase activity of all three receptors.

The cystine knot promotes folding and not thermodynamic stability in vascular endothelial growth factor.

Cystine knots consist of three intertwined disulfide bridges and are considered major determinants of protein stability in proteins in which they occur. We questioned this function and observed that removal of individual disulfide bridges in human vascular endothelial growth factor (VEGF) does not reduce its thermodynamic stability but reduces its unexpected high thermal stability of 108 degrees C by up to 40 degrees C. In wild-type VEGF (deltaG(u,25)(0) = 5.