Signal transduction: Difference between revisions
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In [[biochemistry]], '''signal transduction''' is the " | In [[biochemistry]], '''signal transduction''' is the "intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule ([[hormone]], [[neurotransmitter]]) is mediated via the coupling of a [[cell surface receptor|receptor]]/enzyme to a [[second messenger system]] or to an [[ion channel]]. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the [[gamma-aminobutyric acid]]-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway."<ref>{{MeSH}}</ref> | ||
In [[signal transduction]], [[cell surface receptor]]s may activate [[second messenger system]]s such as adenyl cyclase-[[cyclic AMP]] and [[cyclic GMP]] which then may activate [[protein kinase]]s which then affect downstream targets (see [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?highlight=receptor,kinase,G-protein-coupled&rid=mcb.figgrp.5742 figure]).<ref name="isbn0-7167-3136-3">{{cite book |author=Lodish, Harvey F. |authorlink= |editor= |others= |title=Molecular cell biology |edition= |language= |publisher=Scientific American Books |location=New York |year=1999 |origyear= |chapter=20.1. Overview of Extracellular Signaling|chapterurl=http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mcb.section.5717|pages= |quote= |isbn=0-7167-3136-3 |oclc= |doi= |url=http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mcb |accessdate=}}</ref> | |||
Signal transduction also includes [[synaptic transmission]].<ref>{{MeSH|synaptic transmission}}</ref> | |||
==Classification== | ==Classification== | ||
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===Second messenger systems=== | ===Second messenger systems=== | ||
{{main|Second messenger system}} | {{main|Second messenger system}} | ||
Examples of [[second messenger system]]s include [[cyclic AMP]] | Examples of [[second messenger system]]s include [[cyclic AMP]], [[cyclic GMP]] and the phosphatidylinositol diphosphate-inositol triphosphate system. | ||
These second messengers may activate [[protein kinase]]s who then activate downstream targets. | |||
==References== | ==References== | ||
<references/> | <references/> | ||
Latest revision as of 10:52, 9 July 2009
In biochemistry, signal transduction is the "intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the gamma-aminobutyric acid-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway."[1]
In signal transduction, cell surface receptors may activate second messenger systems such as adenyl cyclase-cyclic AMP and cyclic GMP which then may activate protein kinases which then affect downstream targets (see figure).[2]
Signal transduction also includes synaptic transmission.[3]
Classification
Ion channels
Second messenger systems
Examples of second messenger systems include cyclic AMP, cyclic GMP and the phosphatidylinositol diphosphate-inositol triphosphate system.
These second messengers may activate protein kinases who then activate downstream targets.
References
- ↑ Anonymous (2024), Signal transduction (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Lodish, Harvey F. (1999). “20.1. Overview of Extracellular Signaling”, Molecular cell biology. New York: Scientific American Books. ISBN 0-7167-3136-3.
- ↑ Anonymous (2024), synaptic transmission (English). Medical Subject Headings. U.S. National Library of Medicine.