Receptor rotation aligns activating kinases.
WATERS/MACMILLAN
“The majority of textbooks today still say that cytokine receptor activation is by dimerization,” says Brown. Brown and colleagues add to the accumulating evidence that unbound, inactive receptor is already dimeric by showing that the transmembrane and juxtamembrane domains hold the dimer together in the absence of ligand.
How else might receptor activation work? Another member of the cytokine receptor family, the erythropoietin receptor (EPOR), is thought to be activated by a scissor-like mechanism. The extracellular domains would keep the active faces of the intracellular domains far from each other until ligand binding allows the scissors to close. But when Brown and colleagues crystallized extracellular domains of the...
