G protein, second messenger, relay molecules?

[zool3]

hey im a bit confused between these molecules..G protein, second messenger, relay molecules. can someone please explain the differences.

Thanks in advance!

[seth_129]

A G protein is an example of a secondary messenger molecule that is involved in signal transduction for protein derived of hormones, which interact with surface receptors and require secondary messenger molecules to take their message to the nucleus to enact a response.

[zool3]

ohh okay thanks for that!

[HERculina]

i thought that G proteins werent secondary messengers... O.O
second messengers are usually non-protein.

[Keo]

G-protein's aren't secondary messages, they are more of an activation molecule. They initiate signal transduction causing a cascade of events which activates a whole lot of things such as enzyme production and the production of cAMP.

[zool3]

then what are cAMP and second messengers :S

[Truck]

Cyclic AMP is a secondary messenger. The function of secondary messengers = signal amplification. Essentially, the hormone will bind to the receptor on the cell's membrane, which triggers the G-Protein which in turn will activate the associated secondary messenger thus initiating signal transduction.

[zool3]

ohhhh i get it now! thanks heaps guys