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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


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.
References in periodicals archive ?
In addition, we found that TIIA-induced downregulation of survivin is essential for TIIA to trigger apoptosis and induce TRAIL sensitization.
The role of GRHL2 downregulation in ccRCC has not been investigated, but its target, ZEB1, which is a direct suppressor of GRHL2, is overexpressed in kidney cancer.
Proposed mechanisms whereby TNF-[alpha] inhibitors promote vasculitis include 1) development of antidrug or autoantibodies during TNF-[alpha] blockade that form immune complexes that deposit in the walls of small blood vessels to activate complement and trigger a type III hypersensitivity reaction; 2) changes in T-cell cytokine production; 3) elevation of nuclear antigen levels in the blood because of increased apoptosis of cells targeted by TNF-[alpha] inhibitors; and 4) an increase in the immunogenic load related to downregulation of C-reactive protein by TNF-a inhibitors (7, 8).
Downregulation of mitochondrial telomerase reverse transcriptase induced by H2O2 is Src kinase dependent.
There are 15 chapters: chemistry of reactive species; lipid peroxidation and nitration; protein posttranslational modification; DNA oxidation; downregulation of antioxidants and phase 2 proteins; mitochondrial dysfunction; NADPH oxidases: structure and function; cell signaling and transcription; oxidative stress and redox signaling in carcinogenesis; neurodegeneration from drugs and aging-derived free radicals; cardiac ischemia and reperfusion; atherosclerosis: oxidation hypothesis; cystic fibrosis; biomarkers of oxidative stress in neurodegenerative diseases; synthetic antioxidants.
Osteoblastic differentiation could inhibit osteoclast formation via downregulation of RANKL expression (18,19) and upregulation of osteoprotegerin (OPG) expression (20).
There was a 93% downregulation of telomerase activity and an increase in telomere length of up to 75%.
Since that initial discovery, researchers across the country have built upon Rangnekar's discovery, including a team at the University of Pennsylvania, who recently published findings on how Par-4 downregulation affects breast cancer recurrence.
Downregulation of PCNA and calbindin-D9k protein levels after BPA exposure were confirmed by Western blot analysis (see Supplemental Material, Figure S1B,C).
Hypomethylated states associated with cancer and other pathological conditions often are accompanied by a downregulation of the gene encoding DNMT1 (Hervouet et al.
2007) and the other one is the downregulation of CMKLR1 gene expression at the end of differentiation, which is in agreement with our result (Bozaoglu et al.
The research also revealed that downregulation of Amd1 was necessary for differentiation of ESCs into neural precursor cells and that Amd1 is translationally regulated by a micro-RNA (miRNA), the first ever demonstration of miRNA-mediated regulation of the polyamine pathway.