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Related to downregulation: Upregulation
Cell biology The reduction of a cell’s response to a hormone or other ligand by internalizing its cognate receptor and degrading it within a coated pit; downregulation is a mechanism by which receptors respond to an excess of ligands
Genetics The decrease of a gene’s transcriptional machinery usually by a DNA-binding protein that acts on a regulatory region
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


Development of a refractory or tolerant state consequent on repeated administration of a pharmacologically or physiologically active substance; often accompanied by an initial decrease in affinity of receptors for the agent and a subsequent diminution in the number of receptors.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Molecular Changes Associated with PLK1 Downregulation. PLK1 knockdown produces significant reductions in viability/proliferation and significant increases in apoptosis of clinical patient samples and therapy-resistant MCL cells isolated from different tissue sites.
In decidua, we found an even stronger downregulation in both groups (recurrent miscarriage (IRS 3 versus 0; P = 0.003) and spontaneous abortion (IRS 3 versus 0; P = 0.008) Figure 1(b)).
scabrum the higher dose did not alter regulation while the lower dose upregulated p53 and these two were significantly different (p [less than or equal to] 0.05) from the downregulation of the two doses of C.
To estimate protein synthesis and degradation rates in the context of altered EGFR signaling caused by downregulation of VPS4B, we independently developed an approach called internal standard-assisted synthesis and degradation mass spectrometry (iSDMS) that normalizes protein abundance across different samples and time points and permits the comparison of protein synthesis, degradation, and expression measurements.
The downregulation of a particular gene could result in reduced survival of cardiac myocytes, leading to cardiac failure during a baby's development.
"The question we really need to understand in the future is how much inflammation is needed to fight infection in CF and how much downregulation we can accept in our patients,'" said Dr.
The pYV plasmid-encoded Yop proteins have been implicated in lymphocyte suppression through downregulation of co-stimulatory molecules (13) and impairment of nitric oxide, tumor necrosis factor (TNF)-[alpha], and proinflammatory cytokine production (14).
The idea behind this device is that patients will experience downregulation of the hyperstimulation that is associated with increased emotions and increased habituation.
Of the genes targeted for downregulation of lignin, the caffeic acid 3-O-methyltransferase (OMT) gene has been favored because the maize (Zea mays L.) natural brown midrib bm3 mutants, which are a result of either a deletion or an insertion in the OMT gene (omt), have reduced lignin content and altered lignin composition (Vignols et al., 1995).
Recently, overexpression has been used in tandem with RNA interference (RNAi) to yield rich phenotypic information about the downregulation of a gene.
In an experimental back of the eye, autoimmune uveitis model to be reported in a poster presentation at ARVO, nomacopan and its long acting variants administered intravitreally, reported significant improvement in clinical scoring versus control, co-localization of LTB4 and C5a receptors in retinal inflammatory cells seen for the first time, significant downregulation of pro-inflammatory T-helper 17 cells and the inflammatory cytokine IL-17.