TFR1

Transferrin receptor protein 1 ;
TR ;
TfR ;
TfR1 ;
Trfr ;
T9 ;
p90 ;
CD antigen CD71 ;
[Cleaved into: Transferrin receptor protein 1,serum form ;
sTfR ;
]

function:Cellular uptake of iron occurs via receptor-mediated endocytosis of ligand-occupied transferrin receptor into specialized endosomes. Endosomal acidification leads to iron release. The apotransferrin-receptor complex is then recycled to the cell surface with a return to neutral pH and the concomitant loss of affinity of apotransferrin for its receptor. Transferrin receptor is necessary for development of erythrocytes and the nervous system (By similarity) . A second ligand , the heditary hemochromatosis protein HFE , competes for binding with transferrin for an overlapping C-terminal binding site. ,induction:Regulated by cellular iron levels through binding of the iron regulatory proteins , IRP1 and IRP2 , to iron-responsive elements in the 3'-UTR. Up-regulated upon mitogenic stimulation. ,miscellaneous:Canine and feline parvoviruses bind human and feline transferrin receptors and use these receptors to enter and infect cells. ,miscellaneous:Serum transferrin receptor (sTfR) is used as a means of detecting erythropoietin (EPO) misuse by athletes and as a diagnostic test for anemia resulting from a number of conditions including rheumatoid arthritis , pregnancy , irritable bowel syndrome and in HIV patients. ,PTM:N- and O-glycosylated , phosphorylated and palmitoylated. The serum form is only glycosylated. ,PTM:Palmitoylated on both Cys-62 and Cys-67. Cys-62 seems to be the major site of palmitoylation. ,PTM:Proteolytically cleaved on Arg-100 to produce the soluble serum form (sTfR) . ,similarity:Belongs to the peptidase M28 family. M28B subfamily. ,similarity:Contains 1 PA (protease associated) domain. ,subcellular location:Identified by mass spectrometry in melanosome fractions from stage I to stage IV. ,subunit:Homodimer; disulfide-linked. Binds one transferrin or HFE molecule per subunit. Binds the HLA class II histocompatibility antigen , DR1. Interacts with SH3BP3. Interacts with Machupo arenavirus GPC. ,

response to hypoxia , acute inflammatory response , cellular ion homeostasis , cellular iron ion homeostasis ,endocytosis , defense response , acute-phase response , inflammatory response , aging , response to nutrient , response to wounding , response to extracellular stimulus , response to organic substance , response to inorganic substance ,response to metal ion , response to iron ion , response to manganese ion , membrane invagination , membrane organization , vesicle-mediated transport , cellular homeostasis , cellular cation homeostasis , cellular di- , tri-valent inorganic cation homeostasis , response to nutrient levels , response to retinoic acid , response to vitamin A , response to vitamin , homeostatic process , response to copper ion , chemical homeostasis , ion homeostasis , di- , tri-valent inorganic cation homeostasis , iron ion homeostasis , cation homeostasis , cellular chemical homeostasis , response to oxygen levels ,

Cell membrane ; Single-pass type II membrane protein . Melanosome . Identified by mass spectrometry in melanosome fractions from stage I to stage IV. .; [Transferrin receptor protein 1 , serum form]: Secreted .