Transferrin receptor 1

Transferrin receptor protein 1 (TfR1), also known as Cluster of Differentiation 71 (CD71), is a protein that in humans is encoded by the TFRC gene.[5][6] TfR1 is required for iron import from transferrin into cells by endocytosis.[7][8]

TFRC
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1CX8, 1DE4, 1SUV, 2NSU, 3KAS, 3S9L, 3S9M, 3S9N
Identifiers
Aliases	TFRC, CD71, T9, TFR, TFR1, TR, TRFR, p90, IMD46, transferrin receptor
External IDs	OMIM: 190010 MGI: 98822 HomoloGene: 2429 GeneCards: TFRC
Gene location (Human) Chr. Chromosome 3 (human)[1] Band 3q29 Start 196,027,183 bp[1] End 196,082,189 bp[1]
Gene location (Mouse) Chr. Chromosome 16 (mouse)[2] Band 16 B3|16 23.06 cM Start 32,608,920 bp[2] End 32,632,794 bp[2]
RNA expression pattern More reference expression data
Gene ontology Molecular function • protein homodimerization activity • virus receptor activity • transferrin receptor activity • identical protein binding • double-stranded RNA binding • RNA binding • GO:0001948 protein binding Cellular component • extracellular vesicle • integral component of membrane • recycling endosome • HFE-transferrin receptor complex • endosome • blood microparticle • membrane • melanosome • cell membrane • integral component of plasma membrane • extracellular region • cell surface • basolateral plasma membrane • perinuclear region of cytoplasm • clathrin-coated pit • extracellular exosome • external side of plasma membrane • extracellular • clathrin-coated vesicle membrane • cytoplasmic vesicle • endosome membrane • early endosome Biological process • endocytosis • osteoclast differentiation • positive regulation of bone resorption • receptor-mediated endocytosis • cellular response to drug • regulation of cell proliferation • regulation of cell growth • viral entry • GO:0022415 viral process • cellular iron ion homeostasis • positive regulation of isotype switching • receptor internalization • transferrin transport • positive regulation of B cell proliferation • positive regulation of T cell proliferation • membrane organization • cellular response to leukemia inhibitory factor • iron ion transport Sources:Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	7037	22042
Ensembl	ENSG00000072274	ENSMUSG00000022797
UniProt	P02786	Q62351
RefSeq (mRNA)	NM_001313965 NM_001313966 NM_001128148 NM_003234	NM_011638 NM_001357298
RefSeq (protein)	NP_001121620 NP_001300894 NP_001300895 NP_003225	NP_035768 NP_001344227
Location (UCSC)	Chr 3: 196.03 – 196.08 Mb	Chr 16: 32.61 – 32.63 Mb
PubMed search	[3]	[4]
Wikidata
View/Edit Human View/Edit Mouse

Structure and function

TfR1 = transferrin receptor 1 in Human iron metabolism.

TfR1 is a transmembrane glycoprotein composed of two disulfide-linked monomers joined by two disulfide bonds. Each monomer binds one holo-transferrin molecule creating an iron-Tf-TfR complex which enters the cell by endocytosis.[9]

Clinical significance

TfR1 as a potential new target in cases of human leukemia & lymphoma. InatherYs, in Évry, France, developed a candidate drug, INA01 antibody (anti-CD71) that showed efficacy in pre-clinical studies in the therapy of two incurable orphan oncohematological diseases: the adult T cell leukemia (ATLL) caused by HTLV-1 and the Mantle cell lymphoma (MCL).

TfR1 expressed on the endothelial cells of the blood-brain barrier is used also in preclinical research to allow the delivery of large molecules including antibodies into the brain.[10] Some of the TfR1 targeting antibodies have been shown to cross the blood-brain barrier, without interfering with the uptake of iron. Amongst those are the mouse anti rat-TfR antibody OX26[11] and the rat anti mouse-TfR antibody 8D3.[12] The affinity of the antibody-TfR interaction seems to be important determining the success of transcytotic transport over endothelial cells of the BBB. Monovalent TfR interaction favors BBB transport due to altered intracellular sorting pathways. Avidity effects of bivalent interactions redirecting transport to the lysosome [13]. Also, reducing TfR binding affinity directly promote dissociation from the TfR which increase brain parenchymal exposure of the TfR binding antibody [14].

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[1] Pardridge, Buciak, and Friden, “Selective Transport of an Anti-Transferrin Receptor Antibody through the Blood-Brain Barrier in Vivo.”

Interactions

TfR1 has been shown to interact with GABARAP[15] and HFE.[16][17]

See also

• Transferrin receptor 2
• Cluster of differentiation

References

1. GRCh38: Ensembl release 89: ENSG00000072274 - Ensembl, May 2017
2. GRCm38: Ensembl release 89: ENSMUSG00000022797 - Ensembl, May 2017
3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
5. Sutherland R, Delia D, Schneider C, Newman R, Kemshead J, Greaves M (July 1981). "Ubiquitous cell-surface glycoprotein on tumor cells is proliferation-associated receptor for transferrin". Proceedings of the National Academy of Sciences of the United States of America. 78 (7): 4515–9. doi:10.1073/pnas.78.7.4515. PMC 319822. PMID 6270680.
6. Rabin M, McClelland A, Kühn L, Ruddle FH (November 1985). "Regional localization of the human transferrin receptor gene to 3q26.2----qter". American Journal of Human Genetics. 37 (6): 1112–6. PMC 1684729. PMID 3002171.
7. Aisen P (November 2004). "Transferrin receptor 1". The International Journal of Biochemistry & Cell Biology. 36 (11): 2137–43. doi:10.1016/j.biocel.2004.02.007. PMID 15313461.
8. Moos T (November 2002). "Brain iron homeostasis". Danish Medical Bulletin. 49 (4): 279–301. PMID 12553165.
9. Speeckaert MM, Speeckaert R, Delanghe JR (December 2010). "Biological and clinical aspects of soluble transferrin receptor". Critical Reviews in Clinical Laboratory Sciences. 47 (5–6): 213–28. doi:10.3109/10408363.2010.550461. PMID 21391831.
10. Johnsen KB, Burkhart A, Thomsen LB, Andresen TL, Moos T (October 2019). "Targeting the transferrin receptor for brain drug delivery". Progress in Neurobiology. 181: 101665. doi:10.1016/j.pneurobio.2019.101665. PMID 31376426.
11. Pardridge WM, Buciak JL, Friden PM (October 1991). "Selective transport of an anti-transferrin receptor antibody through the blood-brain barrier in vivo". The Journal of Pharmacology and Experimental Therapeutics. 259 (1): 66–70. PMID 1920136.
12. Lee HJ, Engelhardt B, Lesley J, Bickel U, Pardridge WM (March 2000). "Targeting rat anti-mouse transferrin receptor monoclonal antibodies through blood-brain barrier in mouse". The Journal of Pharmacology and Experimental Therapeutics. 292 (3): 1048–52. PMID 10688622.
13. Niewoehner J, Bohrmann B, Collin L, Urich E, Sade H, Maier P, et al. (January 2014). "Increased brain penetration and potency of a therapeutic antibody using a monovalent molecular shuttle". Neuron. 81 (1): 49–60. doi:10.1016/j.neuron.2013.10.061. PMID 24411731.
14. Yu YJ, Zhang Y, Kenrick M, Hoyte K, Luk W, Lu Y, et al. (May 2011). "Boosting brain uptake of a therapeutic antibody by reducing its affinity for a transcytosis target". Science Translational Medicine. 3 (84): 84ra44. doi:10.1126/scitranslmed.3002230. PMID 21613623.
15. Green F, O'Hare T, Blackwell A, Enns CA (May 2002). "Association of human transferrin receptor with GABARAP" (PDF). FEBS Letters. 518 (1–3): 101–6. doi:10.1016/S0014-5793(02)02655-8. PMID 11997026.
16. Feder JN, Penny DM, Irrinki A, Lee VK, Lebrón JA, Watson N, et al. (February 1998). "The hemochromatosis gene product complexes with the transferrin receptor and lowers its affinity for ligand binding". Proceedings of the National Academy of Sciences of the United States of America. 95 (4): 1472–7. doi:10.1073/pnas.95.4.1472. PMC 19050. PMID 9465039.
17. West AP, Bennett MJ, Sellers VM, Andrews NC, Enns CA, Bjorkman PJ (December 2000). "Comparison of the interactions of transferrin receptor and transferrin receptor 2 with transferrin and the hereditary hemochromatosis protein HFE". The Journal of Biological Chemistry. 275 (49): 38135–8. doi:10.1074/jbc.C000664200. PMID 11027676.

External links

• Overview of all the structural information available in the PDB for UniProt: P02786 (Human Transferrin receptor protein 1) at the PDBe-KB.