Haptocorrin

TCN1
Identifiers
Aliases	TCN1
External IDs	OMIM: 189905; GeneCards: TCN1
Available structures
PDB	Human UniProt search: PDBe RCSB
List of PDB id codes
	4KKI, 4KKJ
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 cell; ; 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
Databases	NCBI: entry; OMA: entry
	6947
	n/a
	ENSG00000134827
	n/a
	P20061
	n/a
	NM_001062
	n/a
	NP_001053
	n/a
	Wikidata
View/Edit Human

Haptocorrin (HC) is a protein that in humans is encoded by the TCN1 gene. Haptocorrin (also known as transcobalamin-1 (TC-1), or cobalophilin) is a glycoprotein that binds to vitamin B₁₂ and protects it from the gastric acid of the stomach. It is also present in the blood where it binds most circulating vitamin B₁₂, rendering it unavailable for uptake by cells (this is conjectured to be a circulating storage function).