basigin basigin basigin (bsg) also known as extracellular matrix metalloproteinase inducer (emmprin) or cluster of differentiation 147 (cd147) is a protein that in humans is encoded by the bsg gene. this protein is a determinant for the ok blood group system. there are three known antigens in the ok system; the most common being oka (also called ok1), ok2 and ok3. basigin has been shown to be an essential receptor on red blood cells for the human malaria parasite, plasmodium falciparum. the common isoform of basigin (basigin-2) has two immunoglobulin domains, and the extended form basigin-1 has three. bsgavailable structurespdbortholog search: a0a087x2b5 pdbe a0a087x2b5 rcsb list of pdb id codes4u0q, 3b5h, 3i84, 3i85, 3qqn, 3qr2identifiersaliasesbsg, 5f7, cd147, emmprin, m6, ok, tcsf, basigin (ok blood group), emprin, slc7a11, hab18gexternal idsomim: 109480 mgi: 88208 homologene: 1308 genecards: bsg gene location (human)chr.chromosome 19 (human)band19p13.3start571,277 bpend583,494 bpgene location (mouse)chr.chromosome 10 (mouse)band10 c1|10 39.72 cmstart79,540,325 bpend79,547,803 bprna expression patternbgeehumanmouse (ortholog)top expressed inleft ventriclestromal cell of endometriumleft adrenal glandbody of stomachanterior pituitaryright uterine tubeleft lobe of thyroid glandascending aortaright lobe of thyroid glandcanal of the cervixtop expressed inmolarinterventricular septummyocardium of ventricleleft lung loberight ventriclespermatocytespermatidcalvariaextensor digitorum longus muscletriceps brachii musclemore reference expression databiogpsmore reference expression datagene ontologymolecular function protein binding mannose binding carbohydrate binding monocarboxylic acid transmembrane transporter activity cadherin binding cell-cell adhesion mediator activity cellular component integral component of membrane membrane focal adhesion melanosome golgi membrane plasma membrane integral component of plasma membrane acrosomal membrane mitochondrion membrane raft sarcolemma extracellular exosome intracellular membrane-bounded organelle axon biological process response to peptide hormone extracellular matrix disassembly extracellular matrix organization odontogenesis of dentin-containing tooth cell surface receptor signaling pathway decidualization pyruvate metabolic process response to mercury ion response to camp embryo implantation leukocyte migration monocarboxylic acid transport protein localization to plasma membrane homophilic cell adhesion via plasma membrane adhesion molecules axon guidance dendrite self-avoidance sources:amigo / quickgoorthologsspecieshumanmouseentrez68212215ensemblensg00000172270ensmusg00000023175uniprotp35613p18572refseq (mrna)nm_001728nm_198589nm_198590nm_198591nm_001322243nm_001077184nm_009768refseq (protein)np_001309172np_001719np_940991np_940992np_940993np_001070652np_033898location (ucsc)chr 19: 0.57 – 0.58 mbchr 10: 79.54 – 79.55 mbpubmed searchwikidataview/edit humanview/edit mouse function basigin is a member of the immunoglobulin superfamily, with a structure related to the putative primordial form of the family. as members of the immunoglobulin superfamily play fundamental roles in intercellular recognition involved in various immunologic phenomena, differentiation, and development, basigin is thought also to play a role in intercellular recognition (miyauchi et al., 1991; kanekura et al., 1991). it has a variety of functions. in addition to its metalloproteinase-inducing ability, basigin also regulates several distinct functions, such as spermatogenesis, expression of the monocarboxylate transporter and the responsiveness of lymphocytes. basigin is a type i integral membrane receptor that has many ligands, including the cyclophilin (cyp) proteins cyp-a and cyp-b and certain integrins. basigin also serves as a receptor for s100a9 and platelet glycoprotein vi, and basigin-1 acts as a receptor for the rod-derived cone viability factor. it is expressed by many cell types, including epithelial cells, endothelial cells, neural progenitor cells and leukocytes. the human basigin protein contains 269 amino acids that form two heavily glycosylated c2 type immunoglobulin-like domains at the n-terminal extracellular portion. a second form of basigin has also been characterized that contains one additional immunoglobulin-like domain in its extracellular portion. interactions basigin has been shown to interact with ubiquitin c. basigin has been shown to form a complex with monocarboxylate transporters in the retina of mice. basigin appears to be required for proper placement of mcts in the membrane. in the basigin null mouse, the failure of mcts to integrate with the membrane may be directly linked to a failure of nutrient transfer in the retinal pigmented epithelium (the lactates transported by mcts 1, 3, and 4 are essential nutrients for the developing rpe), resulting in loss of sight in the null animal. basigin interacts with the fourth c-type lectin domain in the receptor endo180 to form a molecular epithelial-mesenchymal transition suppressor complex that if disrupted results in the induction of invasive prostate epithelial cell behavior associated with poor prostate cancer survival. modulators it have been shown that atorvastatin suppresses cd147 and mmp-3 expression. statins altered cd147 expression, structure and function. role in malaria it has recently (november 2011) been found that basigin is a receptor that is essential to erythrocyte invasion by most strains of plasmodium falciparum, the most virulent species of the plasmodium parasites that cause human malaria. it is hoped that by developing antibodies to the parasite ligand for basigin, rh5, a better vaccine for malaria might be found. basigin is bound by the pfrh5 protein on the surface of the malaria parasite. role in sars-cov-2 infection (covid-19) the host-cell-expressed basigin (cd147) may bind spike protein of sars-cov-2 and possibly be involved in host cell invasion. subsequently, meplazumab, a humanized anti-cd147 antibody, was tested in patients with sars-cov-2 pneumonia. some of these claims have been challenged by another group of scientists who found no evidence of a direct role for basigin in either binding the viral spike protein or promoting lung cell infection. more recent studies suggests cd147 as sars-cov-2 entry receptor of platelets and megakaryocytes, leading to hyperactivation and thrombosis, that differs from common cold coronavirus cov-oc43. incubation of megakaryocytecells with sars-cov-2 resulted in a significant increase in the proinflammatory transcripts lgals3bp and s100a9. notably, cd147 antibody-mediated blocking significantly reduced the expression of s100a9, and s100a8 on megakaryocytes following incubation with sars-cov-2. these data indicate that megakaryocytes and platelets actively take up sars-cov-2 virions, likely via an ace-2-independent mechanism. another study states that platelets challenged with sars-cov-2 undergo activation, dependent on the cd147 receptor. yet sars-cov-2 does not replicate in human platelets.