Human CD71/TFRC/TfR/TfR1/TR/TRFR Protein, ECD (Extracellular Domain), Fc-fusion, Recombinant

TfR (Transferrin Receptor), also known as TfR­1 and CD71, is a single pass, type II transmembrane glycoprotein.  The human TfR gene (TFRC) encodes a 760 amino acids (aa) protein, containing a small (76 aa) N­terminal intracellular domain, a transmembrane (TM) domain, and a 672 aa extracellular domain (ECD). The ECD is composed of a helical, pseudo-peptidase domain, and ligand binding domains, including an RGD potential integrin binding site.  TfR exists as a 188 kDa disulfide­linked homodimer and is expressed on erythroid progenitors, muscle cells and proliferating cells.  TfR acts as a major mediator of cellular iron uptake, it binds and internalizes diferric transferrin, allowing iron release at the low pH of the endosome. Erythroid progenitors, which use iron for hemoglobin synthesis, account for the bulk of total body TfR production.  Most soluble TfR (sTfR) arises from trypsin proteolysis at aa 100, producing the circulating form of TfR.  sTfR concentration in plasma or serum is proportional to total TfR and can be increased due to iron deficiency. Since rapidly growing cells require iron to replicate DNA, cancer cells can express up to 5­fold more TfR than quiescent cells.  Antibody against TfR can inhibit tumor cell proliferation and induce apoptosis.  TfR is also reported to have ferritin­independent functions in T cell development, immunological synapse formation and galectin­3­mediated cell death.

Gene Symbol: TfR; TFRC; TFR1; TFR; T9; TR; p90; CD71; TRFR; IMD46

NCBI Gene ID: 7037

Uniprot Entry: P02786

Construct Details: The recombinant human CD71-Fc fusion is expressed as a 887 amino acid protein consisting of Ala102 - Phe760 region of CD71 and a C-terminal Fc from human IgG1, which exists as a dimer under non-reducing conditions. 

Source: Human cells stably expressing CD71-Fc and growing in chemical-defined media with no animal component or antibiotics

Deduced Amino Acid Sequence: 

        10         20         30         40         50         60
AGTESPVREE PGEDFPAARR LYWDDLKRKL SEKLDSTDFT GTIKLLNENS YVPREAGSQK

        70         80         90        100        110        120
DENLALYVEN QFREFKLSKV WRDQHFVKIQ VKDSAQNSVI IVDKNGRLVY LVENPGGYVA

       130        140        150        160        170        180
YSKAATVTGK LVHANFGTKK DFEDLYTPVN GSIVIVRAGK ITFAEKVANA ESLNAIGVLI

       190        200        210        220        230        240
YMDQTKFPIV NAELSFFGHA HLGTGDPYTP GFPSFNHTQF PPSRSSGLPN IPVQTISRAA

       250        260        270        280        290        300
AEKLFGNMEG DCPSDWKTDS TCRMVTSESK NVKLTVSNVL KEIKILNIFG VIKGFVEPDH

       310        320        330        340        350        360
YVVVGAQRDA WGPGAAKSGV GTALLLKLAQ MFSDMVLKDG FQPSRSIIFA SWSAGDFGSV

       370        380        390        400        410        420
GATEWLEGYL SSLHLKAFTY INLDKAVLGT SNFKVSASPL LYTLIEKTMQ NVKHPVTGQF

       430        440        450        460        470        480
LYQDSNWASK VEKLTLDNAA FPFLAYSGIP AVSFCFCEDT DYPYLGTTMD TYKELIERIP

       490        500        510        520        530        540
ELNKVARAAA EVAGQFVIKL THDVELNLDY ERYNSQLLSF VRDLNQYRAD IKEMGLSLQW

       550        560        570        580        590        600
LYSARGDFFR ATSRLTTDFG NAEKTDRFVM KKLNDRVMRV EYHFLSPYVS PKESPFRHVF

       610        620        630        640        650        660
WGSGSHTLPA LLENLKLRKQ NNGAFNETLF RNQLALATWT IQGAANALSG DVWDIDNEFS

       670        680        690        700        710        720
TGTHTCPPCP APELLGGPSV FLFPPKPKDT LMISRTPEVT CVVVDVSHED PEVKFNWYVD

       730        740        750        760        770        780
GVEVHNAKTK PREEQYNSTY RVVSVLTVLH QDWLNGKEYK CKVSNKALPA PIEKTISKAK

       790        800        810        820        830        840
GQPREPQVYT LPPSREEMTK NQVSLTCLVK GFYPSDIAVE WESNGQPENN YKTTPPVLDS

       850        860        870        880
DGSFFLYSKL TVDKSRWQQG NVFSCSVMHE ALHNHYTQKS LSLSPGK

M.W.: Calculated molecular mass 99.3 kDa; estimated by SDS-PAGE under reducing condition: ~95-100 kDa 

Calculated PI: 6.60

Calculated extinction coefficients (M-1 cm-1, at 280nm):  132295

Purity: >90% judged by SDS-PAGE under reducing condition (see the gel image above, labeled as "S")

Formulation: Supplied at 0.5 mg/ml in sterile PBS pH7.4 (concentration determined by UV spectrometry and verified by SDS-PAGE and Coomassie blue staining). 

Endotoxin Level: <0.1 EU per 1 μg of purified recombinant protein determined by the LAL method

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

The product is shipped at 4°C. Upon receipt, centrifuge the product briefly before opening the vial. It is recommended to store small aliquots at the temperature below –20°C for long-term storage and the product is stable for 6 months. 

Use a manual defrost freezer and avoid repeated freeze-thaw cycles.

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

Additional supporting documents, including PDS, COA and MSDS are available upon request.

FOR RESEARCH USE ONLY. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE IN HUMAN.

Restriction: This product is not transferable or re-sellable.  Customer obtain no right to transfer, assign, or sublicense its use rights, or to transfer, resell, package, or otherwise distribute the product, or to use the product for the benefit of any third party or for any commercial purpose.  Customer may only use the product in compliance with applicable local, state and federal laws, regulations and rules.  Customer may not directly or indirectly use the product or allow the transfer, transmission, export or re-export of all or any part of the product in violation of any export control law or regulation of the united states or any other relevant jurisdiction.  Your use of this product constitutes acceptance of the terms of this limited use agreement.  Please refer to our “terms & conditions” for details.  If you are not willing to accept the limitation of this agreement, G&P Biosciences will accept return of the product for a full/partial refund.