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

The hormone that initiates the signaling pathway is called a first messenger, which activates a second messenger in the cytoplasm, as illustrated in Figure 28.6.

From Textbooks • Jun. 9, 2022

One common alternative system uses calcium ions as a second messenger.

From Textbooks • Jun. 19, 2013

Therefore, they do not directly affect the transcription of target genes, but instead initiate a signaling cascade that is carried out by a molecule called a second messenger.

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

And as we returned, flushed but triumphant, a second messenger met us.

From For The Admiral by Marx, W.J.