UniProt functional annotation for Q9NPF0



	UniProt functional annotation for Q9NPF0

UniProt code: Q9NPF0.

Organism: Homo sapiens (Human).

Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.

Function: Receptor for transcobalamin saturated with cobalamin (TCbl) (PubMed:18779389). Plays an important role in cobalamin uptake (PubMed:18779389, PubMed:20524213). Plasma membrane protein that is expressed on follicular dendritic cells (FDC) and mediates interaction with germinal center B cells (PubMed:10727470). Functions as costimulator to promote B cell responses to antigenic stimuli; promotes B cell differentiation and proliferation (PubMed:10727470, PubMed:11418631). Germinal center-B (GC-B) cells differentiate into memory B-cells and plasma cells (PC) through interaction with T-cells and follicular dendritic cells (FDC) (PubMed:11418631). CD320 augments the proliferation of PC precursors generated by IL-10 (PubMed:11418631). {ECO:0000269|PubMed:10727470, ECO:0000269|PubMed:11418631, ECO:0000269|PubMed:18779389, ECO:0000269|PubMed:20524213}.

Subunit: Interacts (via LDL-receptor class A domains) with TCN2 (PubMed:27411955). {ECO:0000269|PubMed:27411955}.

Subcellular location: Cell membrane {ECO:0000269|PubMed:10727470, ECO:0000269|PubMed:11418631, ECO:0000305|PubMed:18779389}; Single-pass type I membrane protein {ECO:0000305}.

Tissue specificity: Detected in the germinal center (GC) of lymphoid follicles (at protein level) (PubMed:11418631). Expressed abundantly on follicular dendritic cells (FDCs) (PubMed:10727470). {ECO:0000269|PubMed:10727470, ECO:0000269|PubMed:11418631}.

Disease: Methylmalonic aciduria, transient, due to transcobalamin receptor defect (MMATC) [MIM:613646]: A metabolic disorder characterized by increased blood C3-acylcarnitine levels, elevated methylmalonate and homocysteine, and low uptake of transcobalamin-bound cobalamin, but normal conversion to adenosylcobalamin and methylcobalamin. {ECO:0000269|PubMed:20524213, ECO:0000269|PubMed:22819238, ECO:0000269|PubMed:27411955, ECO:0000269|PubMed:27535533}. Note=The disease may be caused by variants affecting the gene represented in this entry.

Annotations taken from UniProtKB at the EBI.


Organism:		Homo sapiens (Human).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.



Function:		Receptor for transcobalamin saturated with cobalamin (TCbl) (PubMed:18779389). Plays an important role in cobalamin uptake (PubMed:18779389, PubMed:20524213). Plasma membrane protein that is expressed on follicular dendritic cells (FDC) and mediates interaction with germinal center B cells (PubMed:10727470). Functions as costimulator to promote B cell responses to antigenic stimuli; promotes B cell differentiation and proliferation (PubMed:10727470, PubMed:11418631). Germinal center-B (GC-B) cells differentiate into memory B-cells and plasma cells (PC) through interaction with T-cells and follicular dendritic cells (FDC) (PubMed:11418631). CD320 augments the proliferation of PC precursors generated by IL-10 (PubMed:11418631). {ECO:0000269\|PubMed:10727470, ECO:0000269\|PubMed:11418631, ECO:0000269\|PubMed:18779389, ECO:0000269\|PubMed:20524213}.


Subunit:		Interacts (via LDL-receptor class A domains) with TCN2 (PubMed:27411955). {ECO:0000269\|PubMed:27411955}.
Subcellular location:		Cell membrane {ECO:0000269\|PubMed:10727470, ECO:0000269\|PubMed:11418631, ECO:0000305\|PubMed:18779389}; Single-pass type I membrane protein {ECO:0000305}.
Tissue specificity:		Detected in the germinal center (GC) of lymphoid follicles (at protein level) (PubMed:11418631). Expressed abundantly on follicular dendritic cells (FDCs) (PubMed:10727470). {ECO:0000269\|PubMed:10727470, ECO:0000269\|PubMed:11418631}.
Disease:		Methylmalonic aciduria, transient, due to transcobalamin receptor defect (MMATC) [MIM:613646]: A metabolic disorder characterized by increased blood C3-acylcarnitine levels, elevated methylmalonate and homocysteine, and low uptake of transcobalamin-bound cobalamin, but normal conversion to adenosylcobalamin and methylcobalamin. {ECO:0000269\|PubMed:20524213, ECO:0000269\|PubMed:22819238, ECO:0000269\|PubMed:27411955, ECO:0000269\|PubMed:27535533}. Note=The disease may be caused by variants affecting the gene represented in this entry.