• Soluble transferrin receptor-1 (sTfR1) concentrations are increased in the plasma under two conditions that are associated with increased iron absorption, i.e. iron deficiency and increased erythropoiesis. (karger.com)
  • Iron, insoluble as free Fe(3+) and toxic as free Fe(2+), is distributed through the body as Fe(3+) bound to transferrin (Tf) for delivery to cells by endocytosis of its complex with transferrin receptor (TfR). (rcsb.org)
  • Although much is understood of the transferrin endocytotic cycle, little has been uncovered of the molecular details underlying the formation of the receptor-transferrin complex. (rcsb.org)
  • An atomic model, obtained by fitting crystal structures of diferric Tf and the receptor ectodomain into the map, shows that the Tf N-lobe is sandwiched between the membrane and the TfR ectodomain and that the C-lobe abuts the receptor helical domain. (rcsb.org)
  • Phorbol ester treatment increases the exocytic rate of the transferrin receptor recycling pathway independent of serine-24 phosphorylation. (rupress.org)
  • In Chinese hamster ovary (CHO) fibroblast cells the protein kinase C activating phorbol ester, phorbol myristate acetate (PMA), stimulates an increase in cell surface transferrin receptor (TR) expression by increasing the exocytic rate of the recycling pathway. (rupress.org)
  • Furthermore, the altered receptor mediates cellular Fe accumulation from diferric-Tf, thereby fulfilling the receptor's major biological role. (rupress.org)
  • Activities affected at 41 degrees C include uptake via the D-mannose 6-phosphate receptor, accumulation of Fe from diferric transferrin, uptake of alpha 2-macroglobulin, compartmentalization of newly synthesized acid hydrolases, resistance to ricin, and sensitivity to diphtheria and Pseudomonas toxins and modeccin. (rupress.org)
  • Iron is released from transferrin when the compound binds with the transferrin receptor on the basolateral surface of hepatocytes. (medscape.com)
  • It is at this location where the HFE protein normally binds to the transferrin receptor, and the iron is brought into the cell along with the deactivated transferrin receptor. (medscape.com)
  • The association between the HFE protein and the transferrin receptor reduces the affinity of the transferrin receptor for diferric transferrin, resulting in a decreased release of iron from the iron-transferrin complex. (medscape.com)
  • One theory is that mutated HFE has a conformation change in its structure that prevents the transferrin receptor from entering the hepatocyte. (medscape.com)
  • The receptor therefore stays active, and continues to bind to diferric transferrin and release iron, leading to iron overload. (medscape.com)
  • The conjugation of biotinylated human holotransferrin (diferric transferrin) and biotinylated anti-CD71 antibody (anti-transferrin receptor antibody) to avidin-conjugated CPNPs (Avidin-CPNPs) permits targeting of transferrin receptors, which are highly expressed on breast cancer cells. (psu.edu)
  • Diferric transferrin binds to its specific receptor and is endocytosed. (diff.org)
  • Other names in common use include diferric transferrin reductase, NADH diferric transferrin reductase, and transferrin reductase. (wikipedia.org)
  • The total iron binding capacity (TIBC) of serum is a measure of total serum transferrin (the three types: apotransferrin, monotransferrin and diferric transferrin) concentration. (mdapp.co)
  • This mechanism is similar to the TFR1 -specific mechanism except that transferrin binds to TFR2. (diff.org)
  • The percentage saturation of transferrin with iron is calculated by dividing the serum iron concentration by the total iron binding capacity (TIBC) and multiplying by 100. (mdapp.co)
  • Lactoferrin is an iron-binding protein similar to transferrin which is present mainly in milk. (diff.org)
  • We conclude .OH formation resulting from protease alteration of transferrin may serve as a mechanism of tissue injury at sites of bacterial infection and other processes characterized by increased proteolytic activity. (duke.edu)
  • Transferrin saturation, measured as a percentage, helps evaluate iron deficiency, anemia or on the contrary, iron overload (in hemosiderosis, iron poisoning or hemochromatosis). (mdapp.co)
  • Decreased transferrin saturation may be caused by an iron-poor diet, impaired iron absorption, pregnancy and lactation or chronic blood loss. (mdapp.co)
  • Increased transferrin saturation may be caused by an iron-rich diet, iron supplements, increased iron absorption or repeated blood transfusions. (mdapp.co)
  • A transferrin saturation value of 30 percent means that 30% of iron-binding sites of transferrin are being occupied by iron. (mdapp.co)
  • Kasvosve I, Delanghe J. Total Iron Binding Capacity and Transferrin Concentration in the Assessment of Iron Status . (mdapp.co)
  • Scholars@Duke publication: Protease-cleaved iron-transferrin augments oxidant-mediated endothelial cell injury via hydroxyl radical formation. (duke.edu)
  • Previous work has shown that the Pseudomonas-derived protease, pseudomonas elastase (PAE), can modify transferrin to form iron complexes capable of catalyzing the formation of hydroxyl radical (.OH) from neutrophil (PMN)-derived superoxide (.O2-) and hydrogen peroxide (H2O2). (duke.edu)
  • Iron associated with transferrin appeared to be responsible for cell injury. (duke.edu)
  • In normal human plasma, transferrin has a concentration of between 25 and 50 μmol/L , and is usually about one-third saturated with iron. (diff.org)
  • The remaining, unoccupied, binding sites on transferrin provide a large buffering capacity in case of an acute increase in plasma iron levels, an important consideration given the toxicity of free iron. (diff.org)
  • Diferrictransferrin previously cleaved with PAE significantly enhanced porcine pulmonary artery endothelial cell monolayer injury from 2.3-6.3 to 15.8-17.0% of maximum, resulting from exposure to H2O2, products of the xanthine/xanthine oxidase reaction, or PMA-stimulated PMNs. (duke.edu)
  • One theory is that mutated HFE undergoes a conformational change in its structure that prevents the transferrin receptor from entering the hepatocyte. (medscape.com)
  • The receptor therefore stays active and continues to bind to diferric transferrin while releasing iron, leading to iron overload. (medscape.com)
  • Diferric transferrin then binds to a transferrin receptor (TFR) on cell membranes, and the iron-transferrin-TFR complex undergoes endocytosis to supply iron for cellular needs. (medscape.com)
  • 1. Src regulates Tyr(20) phosphorylation of transferrin receptor-1 and potentiates breast cancer cell survival. (nih.gov)
  • 2. Characterization of the interaction between diferric transferrin and transferrin receptor 2 by functional assays and atomic force microscopy. (nih.gov)
  • 3. The hereditary hemochromatosis protein, HFE, lowers intracellular iron levels independently of transferrin receptor 1 in TRVb cells. (nih.gov)
  • 4. The role of transferrin receptor 1 and 2 in transferrin-bound iron uptake in human hepatoma cells. (nih.gov)
  • 5. EGFR regulates iron homeostasis to promote cancer growth through redistribution of transferrin receptor 1. (nih.gov)
  • 6. Ferristatin II promotes degradation of transferrin receptor-1 in vitro and in vivo. (nih.gov)
  • 7. The Endocytic Fate of the Transferrin Receptor Is Regulated by c-Abl Kinase. (nih.gov)
  • 11. Lethal iron deprivation induced by non-neutralizing antibodies targeting transferrin receptor 1 in malignant B cells. (nih.gov)
  • 12. miR-148a regulates expression of the transferrin receptor 1 in hepatocellular carcinoma. (nih.gov)
  • 13. Transferrin-directed internalization and cycling of transferrin receptor 2. (nih.gov)
  • 15. H-Ferritin Is Preferentially Incorporated by Human Erythroid Cells through Transferrin Receptor 1 in a Threshold-Dependent Manner. (nih.gov)
  • 16. Gambogic acid, a novel ligand for transferrin receptor, potentiates TNF-induced apoptosis through modulation of the nuclear factor-kappaB signaling pathway. (nih.gov)
  • 17. Characterization of glyceraldehyde-3-phosphate dehydrogenase as a novel transferrin receptor. (nih.gov)
  • Diferric transferrin binds to its specific receptor and is endocytosed. (diff.org)
  • Transferrin (Tf) can specifically recognize the transferrin receptor (TfR) on the surface of the cell membrane, which binds and transports iron into cells. (bvsalud.org)
  • Monitor those at risk with annual measurement of serum ferritin concentration and transferrin saturation starting in early childhood. (nih.gov)
  • Body iron status is routinely assessed by serum ferritin and transferrin saturation, but there is a need of reliable tools for locating iron accumulation in patients. (ashpublications.org)
  • The resulting inhibition causes a reduction in transferrin-bound iron uptake in a variety of cell types, suggesting that HFE is involved in the regulation of iron uptake by TFR1, possibly by limiting the amount of iron released from transferrin. (diff.org)
  • On the surface of target cells the diferric Tf is recognized by two highly specific transferrin receptors (TfRs) TfR1 and TfR2 which allow the cellular uptake of transferrin-bound iron by the receptor-mediated endocytosis. (biotech2012.org)
  • 9. Iron-loaded transferrin potentiates erythropoietin effects on erythroblast proliferation and survival: a novel role through transferrin receptors. (nih.gov)
  • HFE interacts with the helical domain of TFR1, competing with transferrin for its binding site. (diff.org)
  • At endosomal pH, the reduction potential of ferric iron co-ordinated by transferrin is increased when diferric transferrin is complexed to TFR1, suggesting that reduction of iron occurs prior to release from transferrin. (diff.org)