transferrin receptor protein 2; TfR2 (TFR2)

Function

• mediates cellular uptake of transferrin-bound iron (non-iron dependent)
• may be involved in iron metabolism, hepatocyte function & erythrocyte differentiation

Structure

• homodimer
• belongs to the peptidase M28 family, M28B subfamily

Compartment

• cell membrane
• isoform beta: cytoplasm (probable) lacks the transmembrane domain

Alternative splicing

named isoforms=3, alpha, beta, gamma

Expression

• predominantly expressed in liver
• alpha form is also expressed in spleen, lung, muscle, prostate & peripheral blood mononuclear cells
• beta form is weakly expressed in all tissues tested

Pathology

• defects in TFR2 are a cause of hereditary hemochromatosis 3
• the variant Lys-172 found in hereditary hemochromatosis 3 affects the putative initiation codon of the beta isoform thus preventing its translation

More general terms

• cell surface receptor
• glycoprotein

Additional terms

• CD71; transferrin receptor 1; TfR1; TfR; TR; Trfr; T9; p90; sTfR (TFRC)
• serotransferrin; transferrin; Siderophilin; beta-1 metal-binding globulin (TF)

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:7036
• OMIM: https://mirror.omim.org/entry/604250
• OMIM: https://mirror.omim.org/entry/604720
• UniProt: http://www.uniprot.org/uniprot/Q9UP52.html