Haptocorrin

TCN1
Available structures
PDB	Human UniProt search: PDBe RCSB
List of PDB id codes
	4KKI, 4KKJ
Identifiers
Aliases	TCN1, HC, TC-1, TC1, TCI, transcobalamin 1
External IDs	OMIM: 189905; HomoloGene: 47985; GeneCards: TCN1; OMA:TCN1 - orthologs
Gene location (Human)
Chr.	Chromosome 11 (human)
End	59,866,489 bp
RNA expression pattern
	Top expressed in
	pancreatic ductal cell; ; olfactory zone of nasal mucosa; ; trachea; ; parotid gland; ; gallbladder; ; bone marrow; ; bone marrow cells; ; nasal epithelium; ; trabecular bone; ; testicle;
	n/a
	More reference expression data
	n/a
Gene ontology
Molecular function	cobalamin binding;
Cellular component	extracellular region; extracellular space; specific granule lumen; tertiary granule lumen;
Biological process	cobalamin metabolic process; cobalt ion transport; ion transport; cobalamin transport; neutrophil degranulation; transport;
	Sources:Amigo / QuickGO
Orthologs
	6947
	n/a
	ENSG00000134827
	n/a
	P20061
	n/a
	NM_001062
	n/a
	NP_001053
	n/a
	Wikidata
View/Edit Human

Haptocorrin (HC) also known as transcobalamin-1 (TC-1) or cobalophilin is a transcobalamin protein that in humans is encoded by the TCN1 gene. One essential function of haptocorrin is protection of the acid-sensitive vitamin B₁₂ while it moves through the stomach. A second function is serum HC binding of the great majority of circulating vitamin B₁₂, rendering it unavailable for take-up by cells. This is conjectured to be a circulating storage function.