Disease relevance of Emp2

• Recombinant overexpression of EMP2 was studied in B lymphoma and NIH3T3 cells [1].

Psychiatry related information on Emp2

• The absence of this Id in C57BL/6 mice is shown here to be due to the absence of the appropriate VH gene (VHOx-1) usage in the Xmp response [2].

High impact information on Emp2

• EMP2 in both cell types induced cell death on serum deprivation [1].
• Epithelial membrane protein 2, a 4-transmembrane protein that suppresses B-cell lymphoma tumorigenicity [1].
• Recombinant restoration of EMP2 expression in the subline suppressed its tumorigenicity, suggesting that loss of EMP2 was a causal factor in the malignant phenotype [1].
• EMP2 was expressed in the poorly tumorigenic DAC B-lymphoma cell line but was significantly down-regulated in a subline selected for in vivo tumor formation in Balb/c mice [1].
• EMP2-induced cell death correlated with the expression level of EMP2 protein and was prevented by caspase inhibitors Z-VAD and Z-DEVD [1].

Chemical compound and disease context of Emp2

• A highly conserved Id (CRIXmp-1) associated with the murine (BALB/c) humoral immune response to the hapten phthalate (Xmp) is conspicuously absent in C57BL/6 mice [2].

Biological context of Emp2

• Tmp was mapped to mouse chromosome 6, Xmp was mapped to chromosome 16, and Ymp was mapped to chromosome 7 [3].
• They also suggest that EMP2 may influence B-lymphoma tumorigenicity through a functional tumor suppressor phenotype [1].
• The tetraspan protein EMP2 increases surface expression of class I major histocompatibility complex proteins and susceptibility to CTL-mediated cell death [4].
• EMP2 has also recently been recognized as a putative tumor suppressor gene in certain model systems [5].
• The amino acid sequence predicted from the nucleotide sequence of the VKJK from Xmp-specific CRIXmp-1+ hybridomas is identical to the sequence of the anti-arsonate antibody 1210.7, which is the prototype of another Id family (CRI) that is conserved and dominant in BALB/c mice [6].

Anatomical context of Emp2

• Increased expression of EMP2 also influenced the integrin heterodimer repertoire present on the plasma membrane [7].
• These findings suggest that EMP2 facilitates the formation and surface trafficking of lipid rafts bearing GPI-APs, and reduces caveolin expression, resulting in impaired formation of caveolae [8].
• Expression of EMP2 messenger RNA in primary mouse tissues was limited to certain epithelial cell types and the peritoneal lymphoid compartment [1].
• The influence of EMP2 on alphavbeta3 integrin was also observed in vivo as reduction of EMP2 using ribozymes or short hairpin RNA diminished alphavbeta3 integrin expression in glandular and luminal uterine epithelium [9].
• The four-transmembrane protein epithelial membrane protein-2 (EMP2) was recently identified as an endometrial protein necessary for blastocyst implantation, but the mechanism of this role is uncertain [9].

Associations of Emp2 with chemical compounds

• We observed that EMP2 associates with the beta(1) integrin subunit [7].
• The tetraspan protein EMP2 modulates the surface expression of caveolins and glycosylphosphatidyl inositol-linked proteins [8].
• The primary humoral immune response of mice to the hapten phthalate (Xmp) is focused upon two adjacent immunodominant negatively charged carboxyl groups on a benzene ring that are in positions meta and para to the azolinkage (i.e., Xmp) to the protein carrier keyhole limpet hemocyanin [6].

Other interactions of Emp2

• Conversely, a ribozyme construct that specifically cleaves the EMP2 transcript reduced surface GPI-APs and increased caveolin protein expression [8].
• Accordingly, these EMP2-mediated changes resulted in a dramatic alteration in cellular adhesion to extracellular matrix proteins [7].

Analytical, diagnostic and therapeutic context of Emp2

• In this study, we found by laser confocal microscopy that EMP2 was associated with GPI-APs (detected by the GPI-AP binding bacterial toxin proaerolysin) [8].
• Co-immunoprecipitation and immunodepletion experiments indicated that approximately 60% of beta(1) integrins and EMP2 can be isolated in common protein complexes [7].

References