BSG

The protein encoded by this gene is a plasma membrane protein that is important in spermatogenesis, embryo implantation, neural network formation, and tumor progression. The encoded protein is also a member of the immunoglobulin superfamily. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Basigin (Ok Blood Group)

Isoform 1: Essential for normal retinal maturation and development (By similarity).
Acts as a retinal cell surface receptor for NXNL1 and plays an important role in NXNL1-mediated survival of retinal cone photoreceptors (PubMed:25957687).
In association with glucose transporter SLC16A1/GLUT1 and NXNL1, promotes retinal cone survival by enhancing aerobic glycolysis and accelerating the entry of glucose into photoreceptors (PubMed:25957687).
May act as a potent stimulator of IL6 secretion in multiple cell lines that include monocytes (PubMed:21620857).
Isoform 2: Signaling receptor for cyclophilins, essential for PPIA/CYPA and PPIB/CYPB-dependent signaling related to chemotaxis and adhesion of immune cells (PubMed:11943775, PubMed:11688976).
Plays an important role in targeting monocarboxylate transporters SLC16A1/GLUT1, SLC16A11 and SLC16A12 to the plasma membrane (PubMed:17127621, PubMed:21778275, PubMed:28666119).
Acts as a coreceptor for vascular endothelial growth factor receptor 2 (KDR/VEGFR2) in endothelial cells enhancing its VEGFA-mediated activation and downstream signaling (PubMed:25825981).
Promotes angiogenesis through EPAS1/HIF2A-mediated up-regulation of VEGFA (isoform VEGF-165 and VEGF-121) and KDR/VEGFR2 in endothelial cells (PubMed:19837976).
Plays a key role in regulating tumor growth, invasion, metastasis and neoangiogenesis by stimulating the production and release of extracellular matrix metalloproteinases and KDR/VEGFR2 by both tumor cells and stromal cells (fibroblasts and endothelial cells) (PubMed:12553375, PubMed:11992541, PubMed:15833850).
Isoform 1: (Microbial infection) Erythrocyte receptor for P.falciparum RH5 which is essential for erythrocyte invasion by the merozoite stage of P.falciparum isolates 3D7 and Dd2.
Isoform 2: (Microbial infection) Erythrocyte receptor for P.falciparum RH5 which is essential for erythrocyte invasion by the merozoite stage of P.falciparum isolates 3D7, Dd2, 7G8 and HB3 (PubMed:22080952, PubMed:26195724).
Binding of P.falciparum RH5 results in BSG dimerization which triggers an increase in intracellular Ca2+ in the erythrocyte (PubMed:28409866).
This essential step leads to a rearrangement of the erythrocyte cytoskeleton required for the merozoite invasion (PubMed:28409866). Can facilitate human SARS coronavirus (SARS-CoV-1) infection via its interaction with virus-associated PPIA/CYPA. Can facilitate HIV-1 infection via its interaction with virus-associated PPIA/CYPA. First described as a receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it is not required for SARS-CoV-2 infection. Acts as a receptor for measles virus. Promotes entry of pentamer-expressing human cytomegalovirus (HCMV) into epithelial and endothelial cells.

Angiogenesis Source: UniProtKB-KW
Axon guidance Source: GO_Central
Cell surface receptor signaling pathway Source: ProtInc
Decidualization Source: Ensembl
Dendrite self-avoidance Source: GO_Central
Embryo implantation Source: Ensembl
Endothelial tube morphogenesis Source: UniProtKB
Extracellular matrix disassembly Source: Reactome
Extracellular matrix organization Source: Reactome
Homophilic cell adhesion via plasma membrane adhesion molecules Source: GO_Central
Leukocyte migration Source: Reactome
Neural retina development Source: UniProtKB
Neutrophil chemotaxis Source: UniProtKB
Odontogenesis of dentin-containing tooth Source: Ensembl
Photoreceptor cell maintenance Source: UniProtKB
Positive regulation of endothelial cell migration Source: UniProtKB
Positive regulation of interleukin-6 production Source: UniProtKB
Positive regulation of matrix metallopeptidase secretion Source: UniProtKB
Positive regulation of vascular endothelial growth factor production Source: UniProtKB
Positive regulation of viral entry into host cell Source: UniProtKB
Protein localization to plasma membrane Source: ARUK-UCL
Pyruvate metabolic process Source: Reactome
Response to cAMP Source: Ensembl
Response to mercury ion Source: Ensembl
Response to peptide hormone Source: Ensembl

Endoplasmic reticulum membrane; Endosome; Extracellular exosome; Golgi membrane; Mitochondrion; Basolateral plasma membrane; Integral component of plasma membrane; Plasma membrane; Sarcolemma; Acrosomal membrane; Axon; Focal adhesion; Intracellular membrane-bounded organelle; Melanosome; Membrane; Membrane raft; Photoreceptor inner segment; Photoreceptor outer segment

Extracellular: 138-323 aa
Helical: 324-344 aa
Cytoplasmic: 345-385 aa

N-glycosylated.