second messenger


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Related to second messenger: first messenger

second messenger

[′sek·ənd ′mes·ən·jər]
(cell and molecular biology)
Any small molecule or ion that occurs in the cytoplasm of a cell, is generated in response to a hormone binding to a cell-surface receptor, and activates various kinases that regulate the activities of other enzymes.
References in periodicals archive ?
The ISO 9001-certified company has its focus on nucleotide chemistry with a special emphasis on cyclic dinucleotide and cyclic nucleotide analogs of the second messengers 2'3'-cGAMP, c-diGMP, c-diAMP, cAMP, and cGMP.
[16.] Berridge MJ, Irvine RF (1984) Inositol trisphosphate, a novel second messenger in cellular signal transduction.
Ionomycin acts by releasing the cell's sequestered calcium, normally stored in the endoplasmic reticulum, into the cytoplasm where it acts as a second messenger (Morgan and Jacob, 1994).
Differences in drug action during infancy and childhood may relate to alterations in drug target numbers or affinity, or development of second messenger systems.
Second messenger: A signaling molecule that participates in the intracellular reactions resulting when a stimulus, such as a neurotransmitter, binds to a receptor on the cell surface.
Yet it takes as long as four to six weeks for complete symptom relief of depression; this correlates with the time span of "second messenger" activity.
This binding initiates a series of chemical reactions inside the cell, called the second messengers, according to Fitzgerald.
The fourth treatment, theophylline, a phosphodiesterase inhibitor that prevents the breakdown of cyclic adenosine monophosphate (the second messenger produced by adenylyl cyclase), was the only agent that restored cell signaling to normal or supranormal levels but did so at further cost to cell replication.
This results in partnering of two genes, namely BCR and ABL (which encode a tyrosine kinase involved in second messenger systems controlling growth and proliferation.) The resultant fusion protein, BCR-ABL represents an unregulated, permanently switched on tyrosine kinase responsible for phosphorylating tyrosine residues on a number of downstream proteins.
While some sections focus on cutting edge areas of science such as 'Mechanisims of anaesthesia: a role for voltage-gated K channels?' or 'Nanotechnology', the majority offer straightforward clear synopses of areas of basic physiology and pharmacology such as acid-base balance, temperature regulation, receptors and second messenger systems.
We are particularly interested in the signaling cascade that utilizes the phospholipase C b4 (PLCb4) second messenger system.