Nobel Prizes were awarded to the discoverers of G proteins, the G protein-coupled adenylyl cyclase-cAMP system, and nitric oxide. Summarize each of these, and explain the importance of these discoveries to our understanding of signal pathways.

Question

What will be an ideal response?

Answer 1

G proteins are coupled to hundreds of different receptors on cells. These are receptors that bind ligands such as hormones, neurotransmitters, and molecules important in sensory systems. Activated G proteins open ion channels or alter enzyme activity. The G protein-coupled adenylyl cyclase-cAMP system was the first signal transduction pathway discovered, and therefore paved the way for our understanding of signal transduction. cAMP is the second messenger in many signaling systems. Nitric oxide functions as a neurotransmitter, neuromodulator, and paracrine important in cardiovascular regulation.