How does the insulin receptor differ from the erythropoietin receptor?
A) Upon binding its signal molecule, the insulin receptor has two-fold symmetry, while the erythropoietin receptor does not.
B) Both the insulin and erythropoietin receptors trigger MAPK cascades.
C) The insulin receptor contains a tyrosine kinase, while the erythropoetin receptor does not.
D) The insulin receptor is phosphorylated in response to signal molecule binding, while the erythropoietin receptor does not.

Question

Quizplus · Accepted Answer

The insulin receptor is a tyrosine kinase receptor, which means it has intrinsic enzyme activity that can phosphorylate tyrosine residues on itself and other proteins. The erythropoietin receptor, on the other hand, does not have intrinsic tyrosine kinase activity; it associates with cytoplasmic tyrosine kinases (such as JAK2) to transduce its signal.

How Does the Insulin Receptor Differ from the Erythropoietin Receptor