...

"When we know the whole diagram [of signal transduction in all types of cells], we'll know how every cell is controlled. You'll be able to design a drug that works only on the molecule you want and on no other molecule in the body. It will happen. I just can't tell you when."

• –Alfred –Alfred G. Gilman

Work continues as researchers attempt to identify and determine the structure of all the body's receptors and to clarify the role they play in normal functions like human growth, detecting light and odor, and in fighting infection. Here are just three conditions where G-proteins are important:

...