Question

What happens once GPCR activates G-Protein?

a.Activation of Effector Proteins:

b.Production of Second Messengers:

c.Cellular Response Initiation:

d.Termination of Signal:

Answer 1

Upon GPCR activation, the G-Protein is activated, leading to the production of second messengers such as cAMP, which initiate a cellular response, and the signal is terminated when the GTP is hydrolyzed to GDP.

Step-by-step explanation:

Once the GPCR activates the G-Protein, a sequence of events is initiated that leads to cellular responses. This process begins when a ligand binds to the GPCR, causing a conformational change that allows the GPCR to activate the G-Protein by exchanging GDP for GTP on the α subunit. This activated G-Protein can then interact with and activate effector proteins such as adenylyl cyclase, which converts ATP to cAMP, a common second messenger. The cAMP or other second messengers can initiate a signaling cascade that causes changes within the cell, for example, by activating protein kinase A (PKA) or releasing Ca2+ ions. Eventually, the GTP is hydrolyzed back to GDP, and the α subunit and the βγ subunits reassociate, terminating the signal and resetting the G-Protein for another cycle.