second messenger

American  

noun

Biochemistry.

1. any of various intracellular chemical substances, as cyclic AMP, that transmit and amplify the messages delivered by a first messenger to specific receptors on the cell surface.

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second messenger Cultural  

1. A molecule that relays messages in a cell from a receptor on a cell membrane to the final destination where an action within the cell is to take place. (See signal transduction pathway.)

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Etymology

Origin of second messenger

First recorded in 1960–65

Example Sentences

Hormone binding to receptor activates a G-protein, which in turn activates adenylyl cyclase, converting ATP to cAMP. cAMP is a second messenger that mediates a cell-specific response.

From Textbooks • Jun. 9, 2022

The second messenger does not recognize the signal from the receptor.

From Textbooks • Jun. 9, 2022

Not all water-soluble hormones initiate the cAMP second messenger system.

From Textbooks • Jun. 19, 2013

I have sent a messenger and later I have even sent a second messenger, urging the bandits to send a competent agent to expedite our negotiations for the liberation of Mrs. Pawley and Mr. Corkran.

From Time Magazine Archive

He felt that he was restored to consciousness in the right nick of time, for the especial purpose of holding a conference with the second messenger dispatched to him through Jacob Marley's intervention.

From A Christmas Carol by Williams, George Alfred