MAP kinases generally
I. work through the activation of heterotrimeric G-protein coupled receptors
II. require multiple phosphorylations to be activated
III. are specific tyrosine kinases
IV. include PKA among its cascade members

Question

Quizplus · Accepted Answer

MAP kinases generally require multiple phosphorylations to be activated, which is a key characteristic of their activation mechanism. They are not directly activated by heterotrimeric G-protein coupled receptors, are not specific tyrosine kinases (they phosphorylate both serine/threonine and tyrosine residues), and PKA (Protein Kinase A) is not a member of the MAP kinase cascades.

MAP Kinases Generally I. Work Through the Activation of Heterotrimeric G-Protein Coupled Receptors