Acta Biochim Biophys Sin (Shanghai)
June 2009
Interferon-induced transmembrane protein 1 (IFITM1) is an essential mediator of interferon-g-induced antiproliferation. Here, we reported the interaction between IFITM1 and caveolin-1 (CAV-1), and their inhibitory regulatory function on extracellular signal-regulated kinase (ERK). The immunofluorescence staining result showed that IFITM1 localized in caveolae of the plasma membrane and could interact with CAV-1.
View Article and Find Full Text PDFHeparan sulfate proteoglycans (HSPGs) are required for various signaling pathways, one of which is the bone morphogenetic protein (BMP) signaling pathway. N-deacetylase/N-sulfotransferase-1 (NDST1) participates in synthesizing heparan sulfate (HS) chains of HSPGs, and is involved in bone and lung development. Here, we report that in spite of the redundant expression of Ndst2, Ndst3 and Ndst4 genes, Ndst1(-/-) mice display defective differentiation of lung cells and increased cell proliferation.
View Article and Find Full Text PDFPost-transcription modification of proteins can be altered during carcinogenesis. In this study, quantitative sandwich enzyme immunoassays were utilized to explore the clinical diagnostic value of the alternatively glycosylated MUC1 and MUC5AC. Four pairs of antibodies were selected to construct quantitative sandwich enzyme immunoassay.
View Article and Find Full Text PDFSignal transducers and activators of transcription 1 (STAT1) is activated by tyrosine phosphorylation upon interferon-gamma (IFN-gamma) stimulation. Phosphorylated STAT1 translocates into nucleus to initiate the transcription of IFN-gamma target genes that are important in mediating antiviral, antiproliferative, and immune response. The inactivation of STAT1 is mainly accomplished via tyrosine dephosphorylation by the nuclear isoform of T cell protein tyrosine phosphatase (TC45) in nucleus.
View Article and Find Full Text PDFPEG10 is an imprinted gene which is up-regulated in hepatocelluar carcinoma (HCC). However, the mechanism of PEG10 regulation remains to be elucidated. In this work the transcription factors E2F-1 and -4 were demonstrated to bind directly to the promoter of PEG10 and thereby regulate its expression.
View Article and Find Full Text PDFPrevious studies have illustrated that hnRNP K, which could be methylated at arginine residues, plays a key role in coordinating transcriptional responses to DNA damage as a cofactor for p53. In this study, we observed that hnRNP K was markedly arginine methylated in response to UV radiation. Furthermore, arginine methylation of hnRNP K enhanced its affinity with p53.
View Article and Find Full Text PDFWe previously reported that inhibition of SVH-B, a specific splicing variant of SVH, results in apoptotic cell death. In this study, we reveal that this apoptosis may be dependent on the presence of p53. Co-immunoprecipitation and GST pull-down assays have demonstrated that SVH-B directly interacts with p53.
View Article and Find Full Text PDFGlcNAc N-deacetylase/N-sulfotransferase-1 (NDST-1), a member of the enzyme family catalyzing the first modification step in the biosynthesis of heparan sulfate (HS), was knocked out in mice to investigate its role in embryonic development. NDST-1 null mice exhibited delayed endochondral bone formation including shortened calcified zones in limbs, delayed chondrocyte and osteogenetic differentiation, and increased chondrocyte proliferation. In situ HS binding assay revealed that the binding ability of bone morphogenetic protein (BMP) -2, -4, and -6 to endogenous HS was decreased in mutant phalanges, while that of fibroblast growth factor-1 (FGF-1) was not affected.
View Article and Find Full Text PDFCCAAT/enhancer binding protein alpha (C/EBPalpha) is a transcriptional regulatory factor that inhibits cell proliferation, and alternative translational initiation produces two polypeptides, C/EBPalphap30 and C/EBPalphap42. By expression profiling, it was revealed that C/EBPalphap30 specifically inhibited a unique set of genes, including MPP11, p84N5 and SMYD2, which were not affected by C/EBPalphap42 in both QSG-7701 hepatocyte cell line and QGY-7703 hepatoma cells. Semi-quantitative RT-PCR analysis independently confirmed these results.
View Article and Find Full Text PDFA combinatorial human immunoglobulin gene library was constructed from the peripheral lymphocytes of two patients who recovered from severe acute respiratory syndrome (SARS). The library was screened for the production of Fab antibody fragments to a recombinant spike protein of SARS-associated coronavirus (SARS-CoV). One Fab clone, AS3-3, reacted with the spike protein in an enzyme-linked immunosorbent assay.
View Article and Find Full Text PDFSeparation of mutant from nonmutant DNA sequences of 100 bp may be accomplished by using defined denaturing conditions of chemical denaturant and/or elevated temperature during electrophoresis on either polyacrylamide slab gels (denaturing gradient gel electrophoresis, DGGE) or capillary gels (constant denaturant capillary electrophoresis, CDCE). In analysis of mutant directly from a polymerase chain reaction (PCR) product mixture, both have detection sensitivities of approximately 1%. CDCE that facilitates an intermediate mutant enrichment step permits detection of mutants at fractions as low as 2 x 10(-6).
View Article and Find Full Text PDFBackground: Tumor markers are routinely measured in clinical oncology. However, their value in cancer detection has been controversial largely because no single tumor marker is sensitive and specific enough to meet strict diagnostic criteria. One strategy to overcome the shortcomings of single tumor markers is to measure a combination of tumor markers to increase sensitivity and look for distinct patterns to increase specificity.
View Article and Find Full Text PDFSeveral databases have been published to predict alternative splicing of mRNAs by analysing the exon linkage relationship by alignment of expressed sequence tags (ESTs) to the genome sequence; however, little effort has been made to investigate the relationship between cancers and alternative splicing. We developed a program, Alternative Splicing Assembler (ASA), to look for splicing variants of human gene transcripts by genome-wide ESTs alignment. Using ASA, we constructed the biosino alternative splicing database (BASD), which predicted splicing variants for reference sequences from the reference sequence database (RefSeq) and presented them in both graph and text formats.
View Article and Find Full Text PDFHepatocellular carcinoma (HCC) affects males in a significantly higher proportion than females and is one of the human cancers etiologically related to viral factors. Many studies provide strong evidence of the direct role that hepatitis B virus (HBV) plays in hepatic carcinogenesis, but the functions of HBV surface antigen (HBsAg) and X protein (HBx) in hepatocarcinogenesis through direct or indirect mechanisms are still being debated. We generated two HBV gene knock-in transgenic mouse lines by homologous recombination.
View Article and Find Full Text PDFZhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
October 2002
Objective: To explore the relation between genetic polymorphisms of NQO1, GSTT1 and risks of chronic benzene poisoning (BP).
Methods: A case-control study was conducted. 152 BP patients and 152 workers occupationally exposed to benzene without poisoning manifestations were investigated.
Background: Clinical needs often dictate testing for several autoantibodies in a single patient with evidence of autoimmune disease. We developed a microarray containing 15 autoantigens for the detection of autoantibodies in rheumatoid autoimmune diseases.
Methods: We synthesized recombinant centromere protein B, cytokeratin 19, SSA 52-kDa antigen, SSA 60-kDa antigen, SSB antigen, and Jo-1 antigen and prepared anti-nuclear antibody antigens.
To identify genes that are differentially expressed in human esophageal squamous cell carcinoma (ESCC), we have developed a cDNA microarray representing 34 176 clones to analyse gene expression profiles in ESCC. A total of 77 genes (including 31 novel genes) were downregulated, and 15 genes (including one novel gene) were upregulated in cancer tissues compared with their normal counterparts. Immunohistochemistry and Northern blot analysis were carried out to verify the cDNA microarray results.
View Article and Find Full Text PDFZhonghua Zhong Liu Za Zhi
September 2003
Objective: To establish malignant progression associated gene expression profiles in human brain glioma.
Methods: The primary (WHO grade II), recurrent (WHO grade III) and re-recurrent (WHO grade IV) glioma specimens were sequentially collected from one single patient. Gene expression of different tumor specimens and normal brain tissue of the same patient was compared by microarrary techniques.
Suppression subtractive hybridization (SSH) was performed for isolation of tissue-specific genes in nasopharyngeal epithelial tissue, by use of cDNAs from human adult nasopharyngeal epithelial tissue as tester and mixed cDNAs from esophagus, lung, liver, heart, stomach, spleen, skeletal muscle, kidney, and skin as drivers. Fourteen differentially expressed genes in nasopharyngeal epithelial tissue were obtained. Among these genes, LPLUNC1 and SPLUNC1 were confirmed to be specifically expressed in nasopharyngeal epithelial tissue and the trachea.
View Article and Find Full Text PDFEsophageal squamous cell carcinoma (ESCC) is 1 of the most common cancers worldwide. In our study, cDNA microarray comprising 14,803 genes was employed to identify gene-specific expression profile in 6 paired samples of ESCC. Nine genes identified were commonly upregulated and 36 downregulated in tumors, as compared to normal esophageal squamous epithelia.
View Article and Find Full Text PDFHepatocellular carcinoma (HCC) is one of the most common malignant tumors with poor prognosis. By representational difference analysis (RDA), a novel human gene designated SVH, up-regulated in the clinical HCC sample, was identified. The deduced SVH protein consisted of 343 amino acids with a transmembrane domain and an armadillo repeat.
View Article and Find Full Text PDFAim: To obtain the pure sample of SARS small envelope E protein (SARS E protein), study its properties and analyze its possible functions.
Methods: The plasmid of SARS E protein was constructed by the polymerase chain reaction (PCR), and the protein was expressed in the E coli strain. The secondary structure feature of the protein was determined by circular dichroism (CD) technique.
Biochem Biophys Res Commun
February 2003
In this study, a member of the MyoD gene family, AmphiMDF, was isolated from the embryos of amphioxus by degenerate PCR, followed by rapid amplification of cDNA ends (RACE). Southern blot analysis confirmed that only a single myogenic bHLH gene was present in the genome of amphioxus Branchiostoma belcheri tsingtauense. Sequence and phylogenetic analyses indicated that AmphiMDF falls at the base of its vertebrate homologs.
View Article and Find Full Text PDFWe report on the cloning and characterization of a novel gene EC97 which is associated with human esophageal squamous cell carcinoma (ESCC). A fragment of expressed sequence tag (EST) (aa700351) was overexpressed in ESCC tissues compared with the normal tissues in cDNA microarray data. Based on the sequence of aa700351, the full-length cDNA was acquired by polymerase chain reaction (PCR) amplification and named EC97.
View Article and Find Full Text PDFObjective: Establishment of a gene expression profile associated with differentiation inducing the glioma cells was made possible.
Method: The expression level of 18 000 genes in glioma cells was evaluated before and after induction with sodium phenyl-butyrate for 2 hours or 6 days by cDNA array technique, with the results proved by multi-dot blot.
Results: Ninety-eight gene expressions in the glioma cells were changed after the induction, with some genes in transcription and translation systems down-regulated, some oncogenes down-regulated, and some differentiation or apoptosis genes up-regulated.