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Cell-surface Protein (cell-surface + protein)
Selected AbstractsCharacterization of SEZ6L2 cell-surface protein as a novel prognostic marker for lung cancerCANCER SCIENCE, Issue 8 2006Nobuhisa Ishikawa To identify molecules that might serve as biomarkers or targets for development of novel molecular therapies, we have been screening genes encoding transmembrane/secretory proteins that are up-regulated in lung cancers, using cDNA microarrays coupled with purification of tumor cells by laser microdissection. A gene encoding seizure-related 6 homolog (mouse)-like 2 (SEZ6L2) protein, was chosen as a candidate for such molecule. Semi-quantitative RT-PCR and western-blot analyses documented increased expression of SEZ6L2 in the majority of primary lung cancers and lung-cancer cell lines examined. SEZ6L2 protein was proven to be present on the surface of lung-cancer cells by flow cytometrical analysis using anti-SEZ6L2 antibody. Immunohistochemical staining for tumor tissue microarray consisting of 440 archived lung-cancer specimens detected positive SEZ6L2 staining in 327 (78%) of 420 non-small cell lung cancers (NSCLCs) and 13 (65%) of 20 small-cell lung cancers (SCLCs) examined. Moreover, NSCLC patients whose tumors revealed a higher level of SEZ6L2 expression suffered shorter tumor-specific survival compared to those with no SEZ6L2 expression. These results indicate that SEZ6L2 should be a useful prognostic marker of lung cancers. (Cancer Sci 2006; 97: 737,745) [source] Attachment of Neisseria gonorrhoeae to the cellular pilus receptor CD46: identification of domains important for bacterial adherenceCELLULAR MICROBIOLOGY, Issue 3 2001Helena Källström Pili of Neisseria gonorrhoeae mediate binding of the bacteria to human host cells. Membrane cofactor protein (MCP or CD46), a human cell-surface protein involved in regulation of complement activation, acts as a cellular pilus receptor. In this work, we examined which domains of CD46 mediate bacterial adherence. The CD46 expression was quantified and characterized in human epithelial cell lines. N. gonorrhoeae showed the highest adherence to ME180 cells, which have BC1 as the dominant phenotype. The BC isoforms of CD46 were expressed in all cell lines tested. The adherence was not enhanced by high expression of other isoforms, showing that the BC domain of CD46 is important in adherence of N. gonorrhoeae to human cells. To characterize the pilus-binding site within the CD46 molecule, a set of CD46,BC1 deletion constructs were transfected into COS-7 cells. Piliated N. gonorrhoeae attached well to CD46,BC1-expressing COS-7 cells. We show that the complement control protein repeat 3 (CCP-3) and the serine,threonine,proline (STP)-rich domain of CD46 are important for efficient adherence to host cells. Further, partial deletion of the cytoplasmic tail of CD46 results in low bacterial binding, indicating that the cytoplasmic tail takes part in the process of establishing a stable interaction between N. gonorrhoeae and host cells. [source] Dynamic rearrangement of surface proteins is essential for cytokinesisGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 3 2008Tobias Bauer Sequential time-lapse images of a cleaving mouse zygote labeled with fluorescent latex microbeads (red) that bind to cell-surface proteins. These images show that the second polar body moves together with cell-surface proteins, and that the majority of the cell-surface proteins accumulate in the cleavage furrow during cytokinesis. See Bauer et al. in this issue. [source] Staphylococcus aureus SigB activity promotes a strong fibronectin,bacterium interaction which may sustain host tissue colonization by small-colony variants isolated from cystic fibrosis patientsMOLECULAR MICROBIOLOGY, Issue 6 2008Gabriel Mitchell Summary Genes encoding cell-surface proteins regulated by SigB are stably expressed in Staphylococcus aureus small-colony variants (SCVs) isolated from cystic fibrosis (CF) patients. Our hypothesis is that CF-isolated SCVs are locked into a colonization state by sustaining the expression of adhesins such as fibronectin-binding proteins (FnBPs) throughout growth. Force spectroscopy was used to study the fibronectin,FnBPs interaction among strains varying for their SigB activity. The fibronectin,FnBPs interaction was described by a strength of 1000 ± 400 pN (pulling rate of 2 ,m s,1), an energetic barrier width of 0.6 ± 0.1 Å and an off-rate below 2 × 10,4 s,1. A CF-isolated SCV highly expressed fnbA throughout growth and showed a sustained capacity to bind fibronectin, whereas a prototypic strain showed a reduced frequency of fibronectin-binding during the stationary growth phase when its fnbA gene was down-regulated. Reduced expression of fnbA was observed in sigB mutants, which was associated with an overall decrease adhesion to fibronectin. These results suggest that the fibronectin,FnBPs interaction plays a role in the formation of a mechanically resistant adhesion of S. aureus to host tissues and supports the hypothesis that CF-isolated SCVs are locked into a colonization state as a result of a sustained SigB activity. [source] | ||||||||||