ABSTRACT
<p><b>BACKGROUND</b>To explore the feasibility of cloning of the hepatocyte receptor interacting with the Pre S1 protein of HBV by two hybrid system.</p><p><b>METHODS</b>Yeast expression plasmids encoding fusion proteins of full length or portions of Pre S1 of HBV and DNA binding domain of yeast protein GAL4 were constructed and used to transform yeast reporter strain SFY526. Reporter gene product ?galactosidase activity was assayed as a measure of transcription activation in yeast. Mammalian expression plasmid encoding fusion proteins of full length Pre S1 and DNA binding domain of GAL4 was constructed and used to cotransfect hepatoma cell line Huh?7 together with CAT reporter plasmid. Cell extracts were assayed for CAT activity by thin?layer chromatography.</p><p><b>RESULTS</b>The fusion proteins of full length Pre S1 protein and GAL4 DNA binding domain present transcriptional activation function in yeast. The transcription activating sequence is localized to the 21 to 47 amino acids of Pre S1 protein Fusion proteins of full length Pre S 1 and GAL 4 DNA binding domain do not show transcriptional activation function in mammalian cells.</p><p><b>CONCLUSION</b>The transcriptional activating sequence of HBVPre S1 protein in yeast overlaps the hepatocyte receptor binding site. The transcriptional activation function of HBV Pre S1 protein in yeast may prevent researchers?from using yeast two hybrid system to clone HBV receptor interacting with Pre S1 protein. However, the Pre S1 protein does not show transcriptional activation function in mammalian cells. Mammalian two?hybrid system may be a practical method to clone the HBV hepatocyte receptor interacting with Pre S1 protein.</p>
Subject(s)
Humans , DNA-Binding Proteins , Genetics , Fungal Proteins , Genetics , Hepatitis B Surface Antigens , Genetics , Protein Precursors , Genetics , Recombinant Fusion Proteins , Genetics , Transcriptional Activation , Tumor Cells, Cultured , YeastsABSTRACT
Objective To determine circulating specific IgG immune complexes activating complement(IgG/C3-CIC)concentrations in maternal serum of normal term pregnant women and women with pregnancy induced hypertension(PIH).Methods We detect the serum level of IgG/ C3-CIC and IgG in 115 subjects,including 34 cases of normal pregnant women and 81 cases of PIH women.Results The serums concentrations of IgG/C3-CIC in normal term pregnant women, women with mild PHI,moderate PIH and serve PIH were 0.284?0.18,0.303?0.16,0.483?0.286 and 0.462?0.206,respectively.The serum concentration of IgG in the women were 191.07?112. 92g/L,147.56?47.91 g/L,140.18?32.89 g/L and 125.40?53.24 g/L,respectively.The serum concentration of IgG/C3-CIC in patients with moderate PIH and severe PIH was higher than that in patients with mild PIH and normal term pregnant women(P
ABSTRACT
Sinonovacula constricta(Lamarck), a kind of mollusks, is an important species of marine aquaculture. We choose it as our experiment sample and its basic protein expression profiles of hemolymph after short-term treatment ur(?)der high temperature and low salinity were detected, seven kinds of proteins or polypeptides were identified: Cysteine-rich protein 2 CRP2, Phospholipase A2, Pepidyl-prolyl cis- trans isomerase A, epidermal secretory protein xp2 precursor, brain-derived neurotrophic factor, tumor necrosis factor receptor, highmobility groupprotein HMGI-C. They have multiple functions, such as nutrition, gene expression regulation, protein synthesis, substances transport, antitoxin and anti-interference. The results suggested that the hemolymph played a key action in defense System of Sinonovacula constricta .
ABSTRACT
plexes activating complement of 404 cases of healthy persons.It was found that there were thisimmune complexes in every case except umbilical blood,the amount of this immune complexeswere related to age and sex,but not to ABO blood types,which was similar to the relationshipbetween serum IgA and age and sex.These results suggests that the amount of circulating spe-cific IgA immune complexes activating complement in healthy persons depend chiefly on the levelof serum IgA,detecting this immune complexes may approach some characterizations on normalimmune response,and age and sex should be considered when normal value of the specific im-mune complexes is determined