hepatitis b virus (hbv) is considered as a global health concern and hepatitis b surface antigen (hbsag) is the most immunogenic protein of hbv. the purpose of this study was to evaluate the expression of hbsag on the cell surface of human embryonic kidney cell line (hek293t). after transformation of expression vector pcdna/hbsag to e.coli top10f’, plasmid was extracted and digested with bglii....

DNA methylation is one of the mechanism for regulating gene expression. Transfected cells in tissue culture are a mosaic of expression of the exogenous gene. 5’ azacytidine (Aza C), inhibiting nuclear DNA methyltransferase, causes an increase of expression of E.coli a-galactosidase (LacZ) in transfected CHO cells. Murine muscle cell lines G8 and C2C12 were transfected by biolistic technique wit...

Human cells are, in general, poor recipients of foreign DNA, which has severely hampered the cloning of genes by direct phenotypic correction of deficient human cell lines after DNA mediated gene transfer. In this communication a methodology is presented which largely circumvents this problems. The method relies on the use of a recently developed episomal Epstein-Barr-virus-derived cDNA express...

Plants with genes coding for chlorophyll a/bbinding proteins of light-harvesting complex II (LHCII) in antisense orientation (Lhcb) that are characterized by severely reduced Lhcb transcript levels (below 10% of wild type) do not show a bleached phenotype due to a specific loss of the polypeptide. To produce such a phenotype, a conceptually different antisense approach was tested with a dualfun...

Previous studies revealed DNA damage to occur during the toxic action of PaT, a fungal anticodon ribonuclease (ACNase) targeting the translation machinery via tRNA cleavage. Here, we demonstrate that other translational stressors induce DNA damage-like responses in yeast as well: not only zymocin, another ACNase from the dairy yeast Kluyveromyces lactis, but also translational antibiotics, most...

Valsa mali is a causal agent of apple and pear trees canker disease, which is a destructive disease that causes serious economic losses in eastern Asia, especially in China. The lack of an efficient transformation system for Valsa mali retards its investigation, which poses difficulties to control the disease. In this research, a transformation system for this pathogen was established for the f...

Agrobacterium tumefaciens is known to transfer parts of its tumor-inducing plasmid to filamentous fungi including Agaricus bisporus. We have used this transformation system to transform germinating basidiospores of A. bisporus. Analysis of hygromycin B-resistant clones showed that the T-DNA integrated at random sites and in multiple copies into the host genome. Furthermore we have been able to ...