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Type I Transmembrane Protein (type + i_transmembrane_protein)
Selected AbstractsA novel hemocyte-specific membrane protein of Sarcophaga (flesh fly)FEBS JOURNAL, Issue 17 2000Shohei Hori Extensive tissue remodeling takes place during metamorphosis of holometabolous insects. It has been shown that hemocytes play crucial roles in the recognition and elimination of apoptotic cells and larval tissue fragments produced during metamorphosis. We report the immunoaffinity purification, cDNA cloning, and characterization of a prepupal hemocyte membrane protein of Sarcophaga (flesh fly) with a molecular mass of 120 kDa. This protein is a novel type I transmembrane protein with 18 repeats of an epidermal growth factor-like domain in the predicted extracellular region. Expression of the protein was restricted exclusively to prepupal hemocytes. This protein is suggested to be a scavenger receptor for tissue remodeling. [source] Human PARM-1 is a novel mucin-like, androgen-regulated gene exhibiting proliferative effects in prostate cancer cellsINTERNATIONAL JOURNAL OF CANCER, Issue 6 2008Cathrine Fladeby Abstract In this paper we characterize hPARM-1, the human ortholog of rat PARM-1 (prostatic androgen-repressed message-1) and demonstrate its role in prostate cancer. Immunofluorescence microscopy and ultrastructural analysis revealed the localization of hPARM-1 to Golgi, plasma membrane and the early endocytic pathway but not in lysosomes. Biochemical and deglycosylation studies showed hPARM-1 as a highly glycosylated, mucin-like type I transmembrane protein. Analysis of expression of hPARM-1 in various human tissues revealed its presence in most human tissues with especially high expression in heart, kidney and placenta. Androgen controls the expression of the gene as a marked 7-fold increase is seen in the androgen-dependent prostate cancer cell line, LNCaP on androgen stimulation. This is further supported by its decrease in expression in CWR22 xenograft upon castration. Moreover, ectopic expression of hPARM-1 in PC3 prostate cancer cells increased colony formation, suggesting a probable role in cell proliferation. These results suggest that hPARM-1 may have a role in normal biology of the prostate cell and in prostate cancer. © 2007 Wiley-Liss, Inc. [source] Ectodomain shedding of membrane-anchored heparin-binding EGF like growth factor and subcellular localization of the C-terminal fragment in the cell cycleJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2005Fujio Toki Heparin-binding EGF-like growth factor (HB-EGF) is initially synthesized as a type I transmembrane protein (proHB-EGF). The proHB-EGF is shed by specific metalloproteases, releasing the N-terminal fragment into the extracellular space as a soluble growth factor (HB-EGF) and the C-terminal fragment (HB-EGF-C) into the intracellular space, where it prevents transcriptional repression by the promyelocytic leukemia zinc finger protein (PLZF). The goal of the present study was to characterize regulation of proHB-EGF shedding and study its temporal variations in HB-EGF-C localization throughout the cell cycle. Quantitative combination analyses of cell surface proHB-EGF and HB-EGF in conditioned medium showed that proHB-EGF shedding occurred during the G1 cell cycle phase. Laser scanning cytometry (LSC) revealed that HB-EGF-C was internalized into the cytoplasm during the late G1 phase and accumulated in the nucleus beginning in the S phase. Subsequent nuclear export of PLZF occurred during the late S phase. Further, HB-EGF-C was localized around the centrosome following breakdown of the nuclear envelope and was localized to the interzonal space with chromosome segregation in the late M phase. Temporal variations in HB-EGF localization throughout the cell cycle were also characterized by time-lapse imaging of cells expressing YFP-tagged proHB-EGF, and these results were consistent with those obtained in cytometry studies. These results indicate that proHB-EGF shedding and subsequent HB-EGF-C signaling are related with progression of the cell cycle and may provide a clue to understand the unique biological significance of non-receptor-mediated signaling of proHB-EGF in cell growth. © 2004 Wiley-Liss, Inc. [source] Genetic engineering of cytolytic T lymphocytes for adoptive T-cell therapy of neuroblastomaTHE JOURNAL OF GENE MEDICINE, Issue 6 2004Sergio Gonzalez Abstract Background Disease relapse is the leading cause of mortality for children diagnosed with disseminated neuroblastoma. The adoptive transfer of tumor-specific T cells is an attractive approach to target minimal residual disease following conventional therapies. We describe here the genetic engineering of human cytotoxic T lymphocytes (CTL) to express a chimeric immunoreceptor for re-directed HLA-independent recognition of neuroblastoma. Methods The CE7R chimeric immunoreceptor was constructed by PCR splice overlap extension and is composed of a single-chain antibody extracellular domain (scFv) derived from the L1-CAM-specific murine CE7 hybridoma fused to human IgG1 hinge-Fc, the transmembrane portion of human CD4, and the cytoplasmic tail of huCD3-, chain (scFvFc:,). Primary human T cells were genetically modified by naked DNA electrotransfer of plasmid expression vector CE7R-pMG then analyzed by Western blotting, flow cytometry for CE7R expression and cell surface trafficking, 4-h chromium release assay for re-directed neuroblastoma lysis, and ELISA for tumor-specific activation of cytokine production. Results CE7R is expressed as an intact chimeric protein that trafficks to the cell surface as a type I transmembrane protein. Primary human CE7R-expressing CD8+ CTL clones specifically recognize human neuroblastoma tumor cells and are activated for tumor cell lysis and Tc1 cytokine production. Conclusions These data demonstrate the utility of CE7R for re-directing the effector function of CTL to neuroblastoma and have provided the rationale to initiate a FDA-authorized (BB-IND#9149) pilot clinical trial to establish the feasibility and safety of adoptive transfer of autologous CE7R+CD8+ CTL clones to children with recurrent/refractory neuroblastoma. Copyright © 2004 John Wiley & Sons, Ltd. [source] Expression, purification, refolding and crystallization of the carbohydrate-recognition domain of p58/ERGIC-53, an animal C-type lectin involved in export of glycoproteins from the endoplasmic reticulumACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2002Lucas M. Velloso p58/ERGIC-53 is a mammalian calcium-dependent lectin that serves as a glycoprotein-sorting receptor between the endoplasmic reticulum (ER) and the Golgi complex. It is a type I transmembrane protein with two lumenal domains, one of which is a carbohydrate-recognition domain (CRD) and homologous to leguminous lectins. The CRD of p58, the rat homologue of human ERGIC-53, was overexpressed in insect cells and Escherichia coli, purified and crystallized using Li2SO4 as a precipitant. The crystals belong to space group I222, with unit-cell parameters a = 49.6, b = 86.1, c = 128.1,Å, and contain one molecule per asymmetric unit, corresponding to a packing density of 2.4,Å3,Da,1. Knowledge of the structure of p58/ERGIC-53 will provide a starting model for understanding receptor-mediated glycoprotein sorting between the ER and the Golgi. [source] Isolation of a novel mouse gene, mSVS-1/SUSD2, reversing tumorigenic phenotypes of cancer cells in vitroCANCER SCIENCE, Issue 6 2007Tetsuo Sugahara We report isolation of a novel tumor-reversing gene, tentatively named SVS-1, encoding a protein of 820 amino acids with localization on the plasma membrane as a type I transmembrane protein. The gene was found among those downregulated in the activated oncogene-v-K-ras-transformed NIH3T3 cells, Ki3T3, with tumorigenic phenotype. SVS-1 protein harbors several functional domains inherent to adhesion molecules. Histochemical staining of mouse tissues using antibody raised against the protein showed the expression of the protein in restricted regions and cells, for example, strongly positive in apical membranes of epithelial cells in renal tubules and bronchial tubes. The protein inducibly expressed in human fibrosarcoma HT1080 cells and cervical carcinoma HeLa cells was found to be localized primarily on the plasma membrane, as stained with antibodies against FLAG tag in the N -terminus and against the C -terminal peptide of the protein. Expression of the protein in cells induced a variety of biological effects on cancer cells: detachment from the substratum and aggregation of cells and growth inhibition in HeLa cells, but no inhibition in non-tumorigenic mouse NIH3T3 cells. Inhibition of clonogenicity, anchorage-independent growth, migration and invasion through Matrigel was also observed. Taken together these results suggest that the SVS-1 gene is a possible tumor-reversing gene. (Cancer Sci 2007; 98: 900,908) [source] | ||||||||||||||||