Disease relevance of Bsg

• During the organogenesis period, basigin was expressed in various epithelial tissues, brain ventricles, the spinal cord and dorsal root ganglion [1].
• Bsg knock-out mice exhibit infertility of both sexes [2].
• We recently identified CD147 as the main signaling receptor for cyclophilin A. In the current study we examined the contribution of cyclophilin-CD147 interactions to inflammatory responses in vivo using a mouse model of acute lung injury [3].
• At 14 d after intratracheal bleomycin, we found basigin prominently in areas of fibrosis, alveolar macrophages, and bronchiolar epithelium, whereas it was only weakly present in bronchiolar epithelium in untreated mice [4].
• Female sterility in mice lacking the basigin gene, which encodes a transmembrane glycoprotein belonging to the immunoglobulin superfamily [2].

Psychiatry related information on Bsg

• Embryos which survived the critical period yielded Bsg (-/-) mutant mice [5].

High impact information on Bsg

• Hybridoma technology has been used to identify a protein termed neurothelin that is specific for these endothelial cells [6].
• Putting epithelial cells into culture results in concentration of neurothelin at cell-cell contact sites, leaving other cell surface areas devoid of antigen [6].
• However, neurothelin is not found on retinal ganglion cell axons terminating on 1W5-negative brain cells [6].
• Here we describe a 74 kd protein defined by the monoclonal antibody HT7 that is expressed on the surface of chick embryonic blood cells and brain endothelial but on no other endothelial cells [7].
• One of the adhesion molecules that remains expressed in mature, circulating erythrocytes is CD147 [8].

Biological context of Bsg

• Recent reports by this laboratory and others have demonstrated an association between 5A11/Basigin, a member of the immunoglobulin gene superfamily, and monocarboxylate transporter-1 (MCT1), a lactose transporter [9].
• Embigin/basigin subgroup of the immunoglobulin superfamily: different modes of expression during mouse embryogenesis and correlated expression with carbohydrate antigenic markers [1].
• Tissue distribution of basigin and monocarboxylate transporter 1 in the adult male mouse: A study using the wild-type and basigin gene knockout mice [10].
• Most of the spermatocytes in the Bsg (-/-) mouse were arrested and degenerated at the metaphase of the first meiosis, and only a small number differentiated to step 1 spermatids [5].
• A number of studies, including gene targeting, have demonstrated that Bsg plays pivotal roles in spermatogenesis, implantation, neural network formation and tumor progression [11].

Anatomical context of Bsg

• MCT3, which is expressed in the basolateral membrane of the RPE wild-type mouse, was expressed at very low levels in both the apical and basolateral membranes of the Bsg(-/-) mouse [12].
• Dysfunction of the retina in Bsg-deficient mice is ascribed to the failure of plasma membrane integration of MCTs in the tissue [13].
• Bsg was absent but MCT1 was present in Sertoli cells, cauda epididymis, myoepithelial cells and duct of the mandibular gland, surface epithelium of the stomach and bronchioles [10].
• Immunohistochemistry demonstrated that Bsg colocalized with MCT1 in the cerebrum, retina, skeletal and cardiac muscle, duodenal epithelium, hepatic sinusoid, proximal uriniferous tubules, Leydig cells, and efferent ductule epithelium in WT mice [10].
• Thus, basigin mRNA can be considered as a marker of oocyte cytoplasmic maturation in human and mouse species [14].

Associations of Bsg with chemical compounds

• There was no change in expression or distribution of the glucose transporter (GLUT)-1 in the RPE and retina of the Bsg(-/-) mouse [12].
• Basigin and embigin, two related members of the immunoglobulin superfamily, a sialomucin MGC-24 and other glycoproteins were discovered as carriers of developmentally regulated carbohydrate markers [15].
• In contrast, the fundus and the fluorescein fundus angiography and morphology of the retina at the light microscopic level appeared to be normal until 8 weeks of age in Bsg knockout mice [16].
• Basigin (Bsg) is a transmembrane glycoprotein belonging to the immunoglobulin superfamily [2].
• Finally, Bsg (-1-) mice repeatedly visited filter paper impregnated with acetic acid or isozine, indicating an abnormality in either reception of the odor or behavior as to it [17].

Regulatory relationships of Bsg

• RT-PCR analyses of mRNA levels from wild-type and Bsg(-/-) mice demonstrated that the MCT1 transcript was expressed at normal levels in Bsg(-/-) mice [12].
• Caveolin-1 up-regulates CD147 glycosylation and the invasive capability of murine hepatocarcinoma cell lines [18].
• Deglycosylation of CD147 down-regulates Matrix Metalloproteinase-11 expression and the adhesive capability of murine hepatocarcinoma cell HcaF in vitro [19].

Other interactions of Bsg

• Recently, it was reported that targeting of MCT1 and -4 to the plasma membrane requires association with 5A11/basigin (CD147) [12].
• Gene knockout was applied to reveal in vivo function of basigin, syndecan-4 and chondroitin 6-sulfate [15].
• This study investigated the possible role of Cav-1 in CD147 glycosylation in the HcaF, HcaP and Hepa1-6 mouse hepatocarcinoma cell lines, which have high, low and no metastatic potential in the lymph nodes, respectively, and in the normal mouse liver cell line IAR-20 [18].
• A striking homology between the first immunoglobulin (Ig)-like domain of basigin and the fourth Ig-like domain of NCAM, previously shown to bind to oligomannosidic glycans, and the lectin domain of the mannose receptor confirms that basigin is an oligomannose binding lectin [20].
• Also, 5A11/Basigin null retinas were considered 'reactive' based on elevated glial fibrillary acidic protein expression [21].

Analytical, diagnostic and therapeutic context of Bsg

• METHODS: The expression and subcellular distribution of MCTs in Bsg(-/-) mice was analyzed by immunofluorescence microscopy with isoform-specific antibodies [12].
• We generated mutant mice lacking the basigin gene (Bsg) by gene targeting [5].
• The mitogenic response of lymphocytes upon mixed lymphocyte reaction was greater in Bsg (-1-) mice [17].
• We show herein by means of in situ hybridization that Bsg mRNA was expressed in neuroblasts in 13.5 day old mouse embryos [22].
• Northern blot analysis confirmed the strong expression of Bsg in the central nervous system [22].

References