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Definition
 
enEnglish
Second Messenger Systems definition: Systems in which an intracellular signal is generated in response to an intercellular primary messenger such as a hormone or neurotransmitter. They are intermediate signals in cellular processes such as metabolism, secretion, contraction, phototransduction, and cell growth. Examples of second messenger systems are the adenyl cyclase-cyclic AMP system, the phosphatidylinositol diphosphate-inositol triphosphate system, and the cyclic GMP system.
Intracellular Second Messenger definition: Systems in which an intracellular signal is generated in response to an intercellular primary messenger such as a hormone or neurotransmitter. They are intermediate signals in cellular processes such as metabolism, secretion, contraction, phototransduction, and cell growth. Examples of second messenger systems are the adenyl cyclase-cyclic AMP system, the phosphatidylinositol diphosphate-inositol triphosphate system, and the cyclic GMP system.
Signal Transduction definition: 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.
biological signal transduction definition: any process which helps to produce biological responses to events in the environment or internal milieu; e.g., transduction of light into nerve impulses by the retina, or transduction of hormone binding into cellular events by hormone receptors.
signal transduction definition: The cascade of processes by which a signal interacts with a receptor, causing a change in the level or activity of a second messenger or other downstream target, and ultimately effecting a change in the functioning of the cell. [GOC:go_curators]
Signal Transduction definition: Any process by which a cell converts one kind of signal or stimulus into another. Processes referred to as signal transduction often involve a sequence of biochemical reactions inside the cell, which are carried out by enzymes and linked through second messengers.
Transduction, Genetic definition: The transfer of bacterial DNA by phages from an infected bacterium to another bacterium. This also refers to the transfer of genes into eukaryotic cells by viruses. This naturally occurring process is routinely employed as a GENE TRANSFER TECHNIQUE.
genetic transduction definition: virus mediated transfer of genetic material between cells; also refers to the transfer of bacterial DNA by phages.
Signaling Pathway definition: An elaboration of the known or inferred interactions involved in a signal transduction pathway.
phototransduction definition: The sequence of reactions within a cell required to convert absorbed photons into a molecular signal. [GOC:go_curators]
Light Signal Transduction definition: The conversion of absorbed light energy into molecular signals.
visual phototransduction definition: process by which light is converted into electrical signals in the rod and cone cells of the retina or other visual organ; conceptually divided into two phases: activation and inactivation.
Light Signal Transduction, Visual definition: The transducing of light energy to afferent nerve impulses in the retinal rods and cones. After light photons are absorbed by the visual photopigments, the signal is transmitted to the outer segment membrane by the cyclic GMP second messenger system, where it closes the sodium channels. This channel gating ultimately generates an action potential in the inner retina.
detection of stimulus involved in sensory perception definition: The series of events involved in sensory perception in which a sensory stimulus is received by a cell and converted into a molecular signal. [GOC:ai, GOC:dph]
Mechanotransduction, Cellular definition: The process by which cells convert mechanical stimuli into a chemical response. It can occur in both cells specialized for sensing mechanical cues such as MECHANORECEPTORS, and in parenchymal cells whose primary function is not mechanosensory.
signal transduction downstream of smoothened definition: The series of molecular signals that are initiated by the transmembrane protein Smoothened. In the presence of a Hedgehog signaling molecule, the Patched protein no longer inhibits the activity of Smoothened, and Smoothened signals via the Hedgehog signaling complex to activate downstream components of the Hedgehog signaling pathway. [PMID:15057936]
nitric oxide mediated signal transduction definition: A series of molecular signals mediated by the detection of nitric oxide (NO). [GOC:jl]
Rac protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Rac family of proteins switching to a GTP-bound active state. [GOC:bf]
Ras protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Ras superfamily of proteins switching to a GTP-bound active state. [GOC:bf]
Rho protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Rho family of proteins switching to a GTP-bound active state. [GOC:bf]
transduction definition: The transfer of genetic information to a bacterium from a bacteriophage or between bacterial or yeast cells mediated by a phage vector. [ISBN:0198506732 "Oxford Dictionary of Biochemistry and Molecular Biology"]
regulation of signal transduction definition: Any process that modulates the frequency, rate or extent of signal transduction. [GOC:sm]
negative regulation of signal transduction definition: Any process that stops, prevents or reduces the frequency, rate or extent of signal transduction. [GOC:sm]
positive regulation of signal transduction definition: Any process that activates or increases the frequency, rate or extent of signal transduction. [GOC:sm]
detection of chemical stimulus involved in sensory perception of smell definition: The series of events involved in the perception of smell in which an olfactory chemical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of chemical stimulus involved in sensory perception of bitter taste definition: The series of events required for a bitter taste stimulus to be received and converted to a molecular signal. [GOC:go_curators]
detection of chemical stimulus involved in sensory perception of salty taste definition: The series of events required for a salty taste stimulus to be received and converted to a molecular signal. [GOC:go_curators]
detection of chemical stimulus involved in sensory perception of sour taste definition: The series of events required for a sour taste stimulus to be received and converted to a molecular signal. [GOC:go_curators]
detection of chemical stimulus involved in sensory perception of sweet taste definition: The series of events required for a sweet taste stimulus to be received and converted to a molecular signal. [GOC:go_curators]
detection of chemical stimulus involved in sensory perception of taste definition: The series of events involved in the perception of taste in which a gustatory chemical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of chemical stimulus involved in sensory perception of umami taste definition: The series of events required for a bitter taste stimulus to be received and converted to a molecular signal. Umami taste is the savory taste of meats and other foods that are rich in glutamates. [GOC:ai, PMID:11894099]
detection of chemical stimulus involved in sensory perception definition: The series of events in which a sensory chemical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of electrical stimulus during electroception definition: The series of events during electroception in which a sensory electrical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of electrical stimulus involved in sensory perception definition: The series of events in which a sensory electrical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of mechanical stimulus involved in sensory perception definition: The series of events in which a sensory mechanical stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of mechanical stimulus involved in sensory perception of sound definition: The series of events involved in the perception of sound in which a sensory mechanical stimulus is received by a cell and converted into a molecular signal. Sound is picked up in the form of vibrations. [GOC:ai]
Signal Transduction Protein CBLB definition: Cass-Br-M (Murine) Ecotropic Retroviral Transforming Sequence B (CBLB), encoded by the CALB gene, is a member of the CBL family of E3 ubiquitin ligases, which are critical negative regulators of tyrosine kinase signaling pathways in the immune system. Impairment of the CBLB signaling pathway may contribute to human autoimmune diseases, including type 1 diabetes. CBLB contains putative nuclear localization signal, zinc finger, leucine zipper, and proline-rich domains. It associates with three SH3 domain proteins FYN, FGR, and PLCG1. Three isoforms (a long form, truncated isoform 1, truncated isoform 2) are produced by alternative splicing. (From OMIM, PMID and NCI)
AHR Signal Transduction Pathway definition: The Ah receptor, bHLH/PAS transcription factor, upon binding of an agonist such as 2,3,7,8-tetrachlorodibenzo-p-dioxin translocates into the nucleus and heterodimerizes with the transcription factor ARNT. The Ahreceptor/ARNT heterodimer binds to dioxin-responsive elements and alters expression of a number of genes including; CYP1A1, CYP1A2, CYP1B1, and NAD(P)H quinone oxidoreductase. The inactive form of the Ah receptor exists in the cytoplasm as a tetrameric complex composed of the ligand binding subunit, a dimer of the 90-kDa heat shock protein, and X-associated protein 2 (also refered to as AIP or ARA9). (BioCarta)
Cytokine Signaling definition: Cytokine Signaling involves leukocyte secretion of soluble short-range low molecular weight hormone-like intercellular messenger proteins that communicate with immune and other cells to coordinate an immune response. Cytokines primarily stimulate or inhibit activation, differentiation, proliferation, or function of phagocytes, lymphocytes, and hematopoietic stem cells in immune and inflammatory responses to bacteria, virally infected cells, and cancer cells.
IL1R Signaling Pathway definition: Interleukin-1 (IL-1) is a pro-inflammatory cytokine that signals primarily through the type 1 IL-1 receptor (IL-1R1). The activities of IL-1 include induction of fever, expression of vascular adhesion molecules, and roles in arthritis and septic shock. The inflammatory activities of IL-1 are partially derived by transcriptionally inducing expression of cytokines such as TNF-alpha and interferons, as well as inducing the expression of other inflammation-related genes. There are two forms of IL-1 encoded by distinct genes, IL-1 alpha and IL-1 beta. IL-1 beta is produced as a 269 amino acid precursor that is cleaved by IL-1beta converting enzyme (ICE) to the active IL-1 beta form that is secreted. IL-1 signaling is opposed by the naturally occurring peptide IL-1 receptor antagonist which is a therapeutic agent for the treatment of arthritis. The type 1 IL-1 receptor protein binds IL-1 beta but requires the IL-1 receptor accessory protein (IL-1RAcP) to transduce a signal. IL-1 binding causes activation of two kinases, IRAK-1 and IRAK-2, associated with the IL-1 receptor complex. IRAK-1 (IL-1 Receptor Associated Kinase) activates and recruits TRAF6 to the IL-1 receptor complex. TRAF6 activates two pathways, one leading to NF-kB activation and another leading to c-jun activation. The TRAF associated protein ECSIT leads to c-Jun activation through the Map kinase/JNK signaling system. TRAF6 also signals through the TAB1/TAK1 kinases to trigger the degradation of I-kB, and activation of NF-kB. The IL-1 signaling cascade represents a highly conserved response to pathogens through evolution, with homologs in insects and even in plants. The signal transduction cascade utilized by IL-1 receptor is similar to that of TNF, resulting in NF-kB activation, and is most similar to that of the Toll-like receptors that also participate in inflammatory signaling responses to pathogen components like endotoxin (see Toll-like receptor pathway). (BioCarta)
IL7 Signaling Pathway definition: IL-7 is a key cytokine in the immune system, essential for normal development of B cells and T cells. Mice with the IL-7 receptor deleted lack B and T cells. Some humans with SCID (severe combined immunodeficiency disease) also have mutation of their IL-7 receptor gene leading to an absence of T cells and greatly impaired B cell production. The IL-7 receptor includes two polypeptides, a gamma chain and an alpha chain. The alpha-chain is unique to the IL-7 receptor while several other cytokines use the same gamma receptor chain as IL-7, including IL-2, IL-4, IL-9, IL-15 and IL-21. Binding of IL-7 to the alpha chain leads to dimerization of the alpha and gamma chains. JAK3 associated with the gamma chain tyrosine phosphorylates the alpha chain after dimerization. The importance of JAK3 in IL-7 signaling is supported by the similarity of the immune defects in JAK3 knockout mice and IL-7 knockout mice. The phosphorylated alpha chain serves as the site for recruiting other signaling molecules to the complex to be phosphorylated and activated, including STAT5, src kinases, PI3 kinase, Pyk2, and Bcl2 proteins. Some targets of IL-7 signaling contribute to cellular survival, including Bcl2 and Pyk2. Other targets contribute to cellular proliferation, including PI3 kinase, src family kinases (lck and fyn) and STAT5. The transcription factor STAT5 contributes to activation of multiple different downstream genes in B and T cells and may contribute to VDJ recombination through alteration of chromatin structure. The cell survival and cell proliferation signals induced by IL-7 combine to induce normal B and T cell development. (BioCarta)
Gene Transduction Agent definition: Agents used to transport genes or genetic material to a target tissue, including viruses, liposomal encapsulation, direct naked DNA injection, or molecular conjugates.
Signal Transduction Alteration definition: Signal Transduction Alteration involves a change in the quality of existing cellular processes by which a cell propagates information from an extracellular signal through a series of biochemical reactions inside the cell to produce biological responses to events in the environment or internal milieu.
Signal Transduction Induction definition: Signal Transduction Induction involves the initiation of activity in cellular processes by which a cell propagates information from an extracellular signal through a series of biochemical reactions inside the cell to produce biological responses to events in the environment or internal milieu.
Signal Transduction Inhibition definition: Signal Transduction Inhibition involves interference with, or restraint of, the activities in cellular processes by which a cell propagates information from an extracellular signal through a series of biochemical reactions inside the cell to produce biological responses to events in the environment or internal milieu.
signal transduction inhibitors definition: A family of drugs that may prevent the ability of cancer cells to multiply quickly and invade other tissues.
Signal Transduction Inhibitor definition: Substances that inhibit kinase enzymes and other proteins involved in signal transduction pathways to prevent tumor cell growth and induce apoptosis.
Transduction Gene definition: A gene transferred via a vector to a target tissue for use in Gene Therapy.
Visual Signal Transduction Pathway definition: The signal transduction cascade responsible for sensing light in vertebrates is one of the best studied signal transduction processes, and is initiated by rhodopsin in rod cells, a member of the G-protein coupled receptor gene family. Rhodopsin remains the only GPCR whose structure has been resolved at high resolution. Rhodopsin in the discs of rod cells contains a bound 11-cis retinal chromophore, a small molecule derived from Vitamin A that acts as the light sensitive portion of the receptor molecule, absorbing light to initiate the signal transduction cascade. When light strikes 11-cis retinal and is absorbed, it isomerizes to all-trans retinal, changing the shape of the molecule and the receptor it is bound to. This change in rhodopsin's shape alters its interaction with transducin, the member of the G-protein gene family that is specific in its role in visual signal transduction. Activation of transducin causes its alpha subunit to dissociate from the trimer and exchange bound GDP for GTP, activating in turn a membrane-bound cyclic-GMP specific phosphodiesterase that hydrolyzes cGMP. In the resting rod cell, high levels of cGMP associate with a cyclic-GMP gated sodium channel in the plasma membrane, keeping the channels open and the membrane of the resting rod cells depolarized. This is distinct from synaptic generation of action potentials, in which stimulation induces opening of sodium channels and depolarization. When cGMP gated channels in rod cells open, both sodium and calcium ions enter the cell, hyperpolarizing the membrane and initiating the electrochemical impulse responsible for conveying the signal from the sensory neuron to the CNS. The rod cell in the resting state releases high levels of the inhibitory neurotransmitter glutamate, while the release of glutamate is repressed by the hyperpolarization in the presence of light to trigger a downstream action potential by ganglion cells that convey signals to the brain. The calcium which enters the cell also activates GCAP, which activates guanylate cyclase (GC-1 and GC-2) to rapidly produce more cGMP, ending the hyperpolarization and returning the cell to its resting depolarized state. A protein called recoverin helps mediate the inactivation of the signal transduction cascade, returning rhodopsin to its preactivated state, along with the rhodopsin kinase Grk1. Phosphorylation of rhodopsin by Grkl causes arrestin to bind, helping to terminate the receptor activation signal. Dissociation and reassociation of retinal, dephosphorylation of rhodopsin, and release of arrestin all return rhodopsin to its ready state, prepared once again to respond to light. (BioCarta)
Ran protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Ran family of proteins switching to a GTP-bound active state. [GOC:mah]
detection of light stimulus involved in sensory perception definition: The series of events in which a sensory light stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
detection of temperature stimulus involved in sensory perception definition: The series of events in which a sensory temperature stimulus is received by a cell and converted into a molecular signal. [GOC:ai]
adaptation of signaling pathway definition: The negative regulation of a signal transduction pathway in response to a stimulus upon prolonged exposure to that stimulus. [GOC:isa_complete]
ARF protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the ARF family of proteins switching to a GTP-bound active state. [GOC:mah]
Rab protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Rab family of proteins switching to a GTP-bound active state. [GOC:mah]
Ral protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Ral family of proteins switching to a GTP-bound active state. [GOC:mah]
Rap protein signal transduction definition: A series of molecular signals within the cell that are mediated by a member of the Rap family of proteins switching to a GTP-bound active state. [GOC:mah]
Cdc42 protein signal transduction definition: A series of molecular signals within the cell that are mediated by the Cdc42 protein switching to a GTP-bound active state. [GOC:mah]
SMAD protein signal transduction definition: The cascade of processes by which a signal interacts with a receptor, causing a change in the activity of a SMAD protein, and ultimately effecting a change in the functioning of the cell. [GOC:dph, GOC:tb]
 
 
frFrench
transduction definition: Processus par lequel une cellule convertit un type de signal ou de stimulus en un autre type de signal ou de stimulus.
transduction definition: Transfert d’ADN bactérien par l'intermédiaire d’un vecteur viral.
transduction definition: Modification des cellules réceptrices sous l'effet d’une stimulation.
transduction definition: Type de raisonnement typiquement utilisé par des enfants de deux à sept ans.