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 is called a first messenger and the cellular component is called a second messenger.

From Textbooks • Jun. 9, 2022

Serotonin receptors are located on the cell membranes of neurons and activate second messenger cascades that regulate gene expression.

From Textbooks • Jun. 9, 2022

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

From Time Magazine Archive

The second messenger was long absent, and when he did return was near dying with fatigue, but he had a little earth in his paws.

From Narrative of a Second Expedition to the Shores of the Polar Sea by Franklin, John