Theme and variations: juxtamembrane regulation of receptor protein kinases.

Huse et al. in this issue of Molecular Cell and Wybenga-Groot et al. in the September 21, 2001 issue of Cell present biochemical and structural studies that elucidate the roles of juxtamembrane phosphorylation in a receptor serine/threonine kinase, the type I receptor for transforming growth factor beta, and in a receptor tyrosine kinase, the ephrin receptor EphB2.