Reactome | TCN1 binds correnoids in the circulation

TCN1 binds correnoids in the circulation

Stable Identifier

R-HSA-3245898

Type

Reaction [transition]

Species

Homo sapiens

Compartment

extracellular region

ReviewStatus

5/5

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TCN1 binds correnoids in the circulation

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The glycoprotein transcobalamin 1 (TCN1 aka haptocorrin, HC, TCI) binds correnoids, biologically inactive analogs of cobalamin (Cbl). The resulting complexes are cleared rapidly from the blood by hepatocytes and excreted in the urine and bile (Kolhouse & Allen 1977). Structural studies by Furger et al. (2013) and Alam et al. (2016) suggest mechanisms for the differential binding of Cbl over other correnoids by TCN2 in contrast to the broad correnoid specificity of TCN1, consistent with a role for the latter in scavenging and mediating the hepatobiliary excretion of corrinoids.

Literature References

PubMed ID	Title	Journal	Year
915005	Absorption, plasma transport, and cellular retention of cobalamin analogues in the rabbit. Evidence for the existence of multiple mechanisms that prevent the absorption and tissue dissemination of naturally occurring cobalamin analogues Kolhouse, JF, Allen, RH	J Clin Invest	1977
2777761	Structure of the cDNA encoding transcobalamin I, a neutrophil granule protein Berliner, N, Johnston, J, Bollekens, J, Allen, RH	J. Biol. Chem.	1989
23846701	Structural basis for universal corrinoid recognition by the cobalamin transport protein haptocorrin Furger, E, Prota, AE, Fischer, E, Schibli, R, Frei, DC	J Biol Chem	2013
27411955	Structural basis of transcobalamin recognition by human CD320 receptor Zenobi, R, Alam, A, Prinz, B, Locher, KP, Bloch, JS, Woo, JS, Chen, F, Schmitz, J, Root, K	Nat Commun	2016