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

The second messenger can then go on to cause changes in the neuron, such as opening or closing ion channels, metabolic changes, and changes in gene transcription.

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

The second messenger, who had had a moment to draw breath whilst his fellow had been speaking, now broke in with his share of the terrible news.

From In the Wars of the Roses A Story for the Young by Everett-Green, Evelyn