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 studie s that elucidate the roles of juxtamembrane phosphorylation in a receptor s erine/threonine kinase, the type I receptor for transforming growth factor beta, and in a receptor tyrosine kinase, the ephrin receptor EphB2.