In the context of gene regulation: transactivation is the increased rate of gene expression triggered either by biological processes or by artificial means, through the expression of an intermediate transactivator protein.
Transactivation can be triggered either by endogenous cellular or viral proteins, also called transactivators. These protein factors act in trans (i.e., intermolecularly). HIV and HTLV are just two of the many viruses that encode transactivators to enhance viral gene expression. These transactivators can also be linked to cancer if they start interacting with, and increasing expression of, a cellular proto-oncogene. HTLV, for instance, has been associated with causing leukemia primarily through this process. Its transactivator, Tax, can interact with p40, inducing overexpression of interleukin 2, interleukin receptors, GM-CSF and the transcription factorc-Fos. HTLV infects T-cells and via the increased expression of these stimulatory cytokines and transcription factors, leads to uncontrolled proliferation of T-cells and hence lymphoma.
Artificial transactivationedit
Artificial transactivation of a gene is achieved by inserting it into the genome at the appropriate area as transactivator gene adjoined to special promoter regions of DNA. The transactivator gene expresses a transcription factor that binds to specific promoter region of DNA. By binding to the promoter region of a gene, the transcription factor causes that gene to be expressed. The expression of one transactivator gene can activate multiple genes, as long as they have the same, specific promoter region attached. Because the expression of the transactivator gene can be controlled, transactivation can be used to turn genes on and off. If this specific promoter region is also attached to a reporter gene, we can measure when the transactivator is being expressed.
^ ab"receptor transactivation". EMBL. GO Consortium. Retrieved 6 April 2015.
^Beaulieu JM, Espinoza S, Gainetdinov RR (January 2015). "Dopamine receptors - IUPHAR Review 13". Br. J. Pharmacol. 172 (1): 1–23. doi:10.1111/bph.12906. PMC4280963. PMID 25671228. For instance,there are indications that both D1 and D2 receptors can trans-activate the brain-derived neurotrophic factor (BDNF) receptor in neurons (Swift et al., 2011). These two dopamine receptors can also regulate calcium channels through a direct protein–protein interaction in vivo (Kisilevsky and Zamponi, 2008; Kisilevsky et al., 2008). Direct interaction of D1 and D2 receptors and Na+-K+-ATPase has also been demonstrated (Hazelwood et al., 2008; Blom et al., 2012).
transactivation, context, gene, regulation, transactivation, increased, rate, gene, expression, triggered, either, biological, processes, artificial, means, through, expression, intermediate, transactivator, protein, context, receptor, signaling, transactivati. In the context of gene regulation transactivation is the increased rate of gene expression triggered either by biological processes or by artificial means through the expression of an intermediate transactivator protein In the context of receptor signaling transactivation occurs when one or more receptors activate yet another 1 2 receptor transactivation may result from the crosstalk of signaling cascades or the activation of G protein coupled receptor hetero oligomer subunits among other mechanisms 1 Contents 1 Natural transactivation 2 Artificial transactivation 3 See also 4 References 5 External linksNatural transactivation editTransactivation can be triggered either by endogenous cellular or viral proteins also called transactivators These protein factors act in trans i e intermolecularly HIV and HTLV are just two of the many viruses that encode transactivators to enhance viral gene expression These transactivators can also be linked to cancer if they start interacting with and increasing expression of a cellular proto oncogene HTLV for instance has been associated with causing leukemia primarily through this process Its transactivator Tax can interact with p40 inducing overexpression of interleukin 2 interleukin receptors GM CSF and the transcription factor c Fos HTLV infects T cells and via the increased expression of these stimulatory cytokines and transcription factors leads to uncontrolled proliferation of T cells and hence lymphoma Artificial transactivation editArtificial transactivation of a gene is achieved by inserting it into the genome at the appropriate area as transactivator gene adjoined to special promoter regions of DNA The transactivator gene expresses a transcription factor that binds to specific promoter region of DNA By binding to the promoter region of a gene the transcription factor causes that gene to be expressed The expression of one transactivator gene can activate multiple genes as long as they have the same specific promoter region attached Because the expression of the transactivator gene can be controlled transactivation can be used to turn genes on and off If this specific promoter region is also attached to a reporter gene we can measure when the transactivator is being expressed See also editTransrepression Selective glucocorticoid receptor agonistReferences edit a b receptor transactivation EMBL GO Consortium Retrieved 6 April 2015 Beaulieu JM Espinoza S Gainetdinov RR January 2015 Dopamine receptors IUPHAR Review 13 Br J Pharmacol 172 1 1 23 doi 10 1111 bph 12906 PMC 4280963 PMID 25671228 For instance there are indications that both D1 and D2 receptors can trans activate the brain derived neurotrophic factor BDNF receptor in neurons Swift et al 2011 These two dopamine receptors can also regulate calcium channels through a direct protein protein interaction in vivo Kisilevsky and Zamponi 2008 Kisilevsky et al 2008 Direct interaction of D1 and D2 receptors and Na K ATPase has also been demonstrated Hazelwood et al 2008 Blom et al 2012 External links editTransactivators at the U S National Library of Medicine Medical Subject Headings MeSH Retrieved from https en wikipedia org w index php title Transactivation amp oldid 1003977356, wikipedia, wiki, book, books, library,
