Which of the following sequences is correct?
A. binding of a signaling molecule to its receptor → G protein activation → adenylyl cyclase activation → cAMP production → protein phosphorylation
B. diffusion of a signaling molecule across the plasma membrane → binding of the signaling molecule to its receptor → movement of the signaling molecule-receptor complex into the nucleus → transcription
C. binding of a growth factor to its receptor → phosphorylation cascade → activation of transcription factor → transcription
D. binding of a signaling molecule to its receptor → G protein activation → phospholipase C activation → IP3 production → increase in cytoplasmic calcium concentration
E. All of the choices are correct.
Answer: E