Transferrin receptor 2
| Transferrin receptor 2 | ||
|---|---|---|
| Properties of human protein | ||
| Mass / length primary structure | 801/630/774 amino acids (α / β / γ) | |
| Secondary to quaternary structure | α, γ: transmembrane receptor β: cytosolic | |
| Isoforms | α, β, γ | |
| Identifier | ||
| Gene name | TFR2 | |
| External IDs | ||
| Occurrence | ||
| Parent taxon | Vertebrates | |
Transferrin receptor 2 ( TfR2 ) hot proteins in vertebrates , by the TfR2 - gene encodes be and isoforms of each other. In humans there are three of these isoforms, which are called TfR2α, TfR2β and TfR2γ and have different functions. TfR2α is a transmembrane receptor and is responsible for the transport of ferritin into the mitochondria ; it is mainly expressed in the liver and dopaminergic neurons in the substantia nigra , but also in the spleen , lungs , muscles , prostate and PBMCs . The transmembrane component is missing in TfR2β; it is found in small amounts in the cytosol of all cell types. Mutations in the TfR2 gene are responsible for type III of the iron storage disease hemochromatosis .
TfR2 has a novel mitochondrial signal sequence that is missing from the β isoform . The transmembrane isoforms are therefore localized in the mitochondrial membrane, where they mediate the endocytosis of the cytosolic transferrin.
The mutation responsible for hemochromatosis is not only the variant Lys-172, which leads to the complete stop of TfR2β expression, but also those in the localization sequence of the gene. In this case TfR2α and TfR2γ are unable to leave the ER after transcription.
In addition to TfR2, there is also the transferrin receptor 1.
Individual evidence
- ↑ Homologues at OMA
- ↑ a b UniProt Q9UP52
- ↑ a b Mastroberardino PG, Hoffman EK, Horowitz MP, et al. : A novel transferrin / TfR2-mediated mitochondrial iron transport system is disrupted in Parkinson's disease . In: Neurobiol. Dis. . 34, No. 3, June 2009, pp. 417-31. doi : 10.1016 / j.nbd.2009.02.009 . PMID 19250966 . PMC 2784936 (free full text).
- ↑ Wallace DF, Summerville L, Crampton EM, Subramaniam VN: Defective trafficking and localization of mutated transferrin receptor 2: implications for type 3 hereditary hemochromatosis . In: Am. J. Physiol., Cell Physiol. . 294, No. 2, February 2008, pp. C383-90. doi : 10.1152 / ajpcell.00492.2007 . PMID 18094142 .