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

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

This intracellular mediator is called the second messenger.

From Textbooks • Jun. 19, 2013

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

From Textbooks • Jun. 19, 2013

"I like to call it a second messenger," said Sutherland of AMP.

From Time Magazine Archive

That same evening a second messenger started northward after Maurice Gordon with a letter telling him to come back at once to Loango.

From With Edged Tools by Merriman, Henry Seton