Disease relevance of EMP2

• Thus, the function of EMP2 during regulation of the heat stress response can be separated from its role in plant development [1].
• The objective of this study was to determine the prevalence of EMP2 expression in endometrial neoplasms and its clinical significance [2].
• Expression of epithelial membrane protein-2 is associated with endometrial adenocarcinoma of unfavorable outcome [2].
• These findings suggest that EMP2 may be a potential pharmacologic target for human endometrial cancer [3].
• Using anti-EMP2 diabody, we evaluated the in vitro response of nine human ovarian cancer cell lines with detectable EMP2 expression [4].

High impact information on EMP2

• In one strain of parasite there was a significant difference in relative mobility of the 125I-surface-labeled Pf EMP 1 and the biosynthetically labeled Pf EMP 2, further distinguishing these proteins [5].
• The mAbs did not react with the surface of intact infected erythrocytes, nor was Pf EMP 2 accessible to exogenous proteases or lactoperoxidase-catalyzed radioiodination of intact cells [5].
• Transport of an Mr approximately 300,000 Plasmodium falciparum protein (Pf EMP 2) from the intraerythrocytic asexual parasite to the cytoplasmic face of the host cell membrane [5].
• Despite the recessive emp2 phenotype, steady state levels of emp2 transcripts were abundant in mutant kernels, and the predicted coding region was unaffected [6].
• Furthermore, the developmental retardation of emp2 mutant kernels before the HSR suggests an additional role for EMP2 during embryo development distinct from the HSR [6].

Biological context of EMP2

• A screen for proteins that associate with the C-terminal domain of the P2X(7) receptor and might mediate the blebbing phenotype, identified epithelial membrane protein 2 (EMP-2) [7].
• The epithelial membrane protein 2 gene (EMP2), which maps to chromosome 16p13.2, was evaluated as a candidate gene for CMT1C [8].
• Previous analyses revealed that EMP2 is required for regulation of heat shock protein (hsp) gene expression and also for embryo morphogenesis [1].
• Embryo-lethal recessive emp2 mutations revealed that EMP2 is required for the down-regulation of hsp transcription during embryogenesis, whereas accumulation of HSBP2 is induced in seedlings following heat shock [9].
• EMP2 controls surface levels of several classes of integrin and other cell-interaction molecules, and their trafficking to glycolipid-enriched lipid raft domains is important in receptor signaling [2].

Anatomical context of EMP2

• Since alphavbeta3 integrin is an important endometrial molecule involved in blastocyst interaction, we evaluated the role of EMP2 in modulating integrin expression in the HEC1A endometrial cell line and endometrial epithelium in vivo [10].
• Normally, EMP2 is expressed at discrete locations in the body including high levels in the eye, lung, heart, thyroid, and uterus [11].
• Epithelial membrane protein-2 regulates surface expression of alphavbeta3 integrin in the endometrium [10].
• BACKGROUND: Epithelial membrane protein 2 (EMP2) is an estrus-regulated tetraspan protein that is required for endometrial competence in blastocyst implantation [2].
• EMP2-positive tumors were more likely than others to be myometrium invasive, high stage, and recurrent, persistent, or fatal [2].

Associations of EMP2 with chemical compounds

• The interaction between EMP-2 and P2X(7) was confirmed biochemically by co-immunoprecipitation, co-purification, and glutathione S-transferase pull-down assays, and this interaction was entirely dependent on the C-terminal domain of P2X(7) [7].
• In other cell types, EMP2 controls delivery of certain classes of proteins to the cell surface, including various integrin isoforms (a class of receptors implicated in endometrial-blastocyst interaction) [10].

Other interactions of EMP2

• In vitro transcription-translation generates EMP-2 and EMP-3 polypeptides of 18 kDa which is in agreement with their predicted sizes [12].
• Antibodies raised against Pf EMP 2/MESA did not precipitate Pf EMP 1 [13].
• The maize heat shock factor-binding protein paralogs EMP2 and HSBP2 interact non-redundantly with specific heat shock factors [9].

Analytical, diagnostic and therapeutic context of EMP2

• A multivariate analysis of disease-free survival demonstrated independent, negative prognostic significance for EMP2 expression, high stage, and high-risk histologic subtypes [2].
• Cloning and sequence analyses revealed that the emp2 gene encoded a predicted protein with high similarity to HEAT SHOCK BINDING PROTEIN1, which was first described in animals as a negative regulator of the HSR. emp2 is a loss-of-function mutation of an HSR-negative regulator in plants [6].

References