hFSH is a glycoprotein secreted from anterior pituitary and consists of α and β subunits. Because of its major biological functions including sperm formation in the male and for follicular growth, FSH is used to cure woman's sterility. In this study we tried to produce recombinant hFSH in vitro using a retrovirus expression vector. Two major components of the vector we constructed are: (ⅰ) a DNA fragment containing α and β genes fused by a DNA sequence coding carboxyl terminal peptide (CTP) of human chorionic gonadotropin, (ⅱ) a DNA fragment corresponding woodchuck hepatitis virus posttranscriptional regulatory element (WPRE). Evaluation of expression profile of the recombinant FSH using reverse transcription PCR and enzyme-linked immunosorbent assay (ELISA). Among three cell lines tested, HeLa cells were the best for hFSH expression (5,395 mIU/ml), then followed by chicken embryonic fibroblast (CEF) cells and Chinese hamster ovary (CHO) cells in the order of hFSH production. In addition to the amount, the FSH produced from HeLa cells was highest in terms of biological activity which was determined by measuring cAMP.

Ceriporiopsis subvermispora is a unique white rot fungus degrading plant cell wall lignin without severe loss of cellulose. Recombinant plasmids containing homologous gene expression signals fused to the coding sequence of Escherichia coli hph which encodes for hygromycin phosphotransferase were introduced in protoplasts of wild type C. subvermispora using PEG/CaCl2 protocol. A number of hygromycin B resistant strains were isolated on a screening plate containing 100㎍/ml of hygromycin B: whereas, no colonies were observed when protoplasts were treated with no DNA as a negative control. It was demonstrated that most of the isolates lost their drug resistance during successive cultivations in the presence of the same concentration of hygromycin B, but some of the isolates showed stable drug resistance after five times repeated screening. They did not lose the drug resistance even after the cultivation in the absence of hygromycin B and incorporation of the hph sequence was confirmed by specific amplification of the target sequence in PCR experiments and Southern hybridization analysis. The stable transformation system will make it possible to do molecular genetic analysis, as well as breeding of genetically modified strains, in C. subvermispora. Moreover, it was demonstrated that recombinant constructs with truncated promoter showed reduced number of the drug resistant isolates on the first screening plate, in response with the length of the remaining promoter sequence. These findings indicated that unstable drug resistance observed in these isolates should originate from transient expression of the introducing marker genes, and that a promoter assay system has been developed for the first time in basidiomycete. This system is practically not affected by the positional effect of the integrated recombinant gene in the host chromosome.

Many methods have been developed for more efficient gene delivery and expression in human cells. A number of studies have been performed in achieving successful gene delivery and expression conditions. We investigated differential gene expression patterns after delivery adenoviral vector containing green fluorescent protein(GFP) gene into human cancer cell lines. We constructed recombinant adenoviral Ad-CMV-GFP containing CMV promoter and GFP gene. The efficiency of gene expression was assessed by observation GFP expressing cells using fluorescent microscopy after transfer of Ad-CMV-GFP in concentrations of 0.1μl. 1μl. 10μl. At first, we evaluated expression patterns of gene in several human cancer cell lines, gastric adenocarcinoma cell line AGS was showed high level of GFP expression compared with colorectal adenocarcinoma cell line HT-29. After transfer 0.1μl of Ad-CMV-GFP in AGS, we could found that GFP expression cells were observed in next day and highly increased 2 days. While, small number of GFP expressing cells were examined in HT-29 and SNU-C4. Therefore, these data showed that AGS was expressed the highest level of GFP and almost AGS cells seems to express GFP in concentration of 1μl of Ad-CMV-GFP. GFP expression pattern in HT-29 reveal that expression was low in next day after gene transfer but significantly increase expression level in 2 days. In case of SNU-C4, GFP expression increased with increasing concentration of Ad-CMV-GFP and t ransfer times. For examine effects of transfer times in small amount gene, we transfer in concentration of 0.1μl Ad-CMV-GFP and detected GFP expression patterns after 2 days or 4 days. As a result, expression level of GFP in AGS was increase about 2 fold after 4 days compared with 2 days, but any difference of GFP expression levels were not showed in HT-29 and SNU-C4. Our study suggested that adenovirus was very efficient gene transfer vector for gene expression in human cancer cell lines. In addition to, we also demonstrated that gene expression patterns was dependent on each human cell lines. Therefore, further studies will be needed to confirm the optimum conditions for efficient gene delivery and expression in each target cell lines with consideration to cellular properties.

To determine differential gene expression profiles in the salivary gland of a predatory flower bug species, Orius laevigatus Fieber, a subtractive cDNA library was constructed by suppression subtractive hybridization. The major transcripts encoding trypsins (28.6% of the total ESTs) were eliminated from the library and then remaining salivary gland-specific genes were searched. A total of 513 expressed sequence tags (ESTs) were clustered and assembled into 129 contigs (64 multiple sequences and 65 singletons). About 58% were matched with insect genes. In total, 38 genes (179 ESTs) were found from the library by BLASTx search. A hemolysin-like protein occupied ca. 8% (41 ESTs) of the library. Hemolysin is known to destruct cells including blood cells by forming pores on the cell membrane. A hemolysin-like salivary protein of O. laevigatus might be hemolytic against the prey cells, thereby allowing O. laevigatus to facilitate feeding. Several contigs encoding lipase was also identified from the salivary gland-specific library. Discovery of salivary gland-specific genes should promote further studies on biologically active components in the saliva of O. laevigatus.

We report here the production of transgenic chickens that can regulate human erythropoietin (hEPO) gene expression. The glycoprotein hormone hEPO is an essential for viability and growth of the erythrocytic progenitors. Retrovirus vector system used in this study has two features including tetracycline-controllable promoter and woodchuck hepatitis virus posttranscriptional regulator element (WPRE). The former is for to reduce the possibility of physiological disturbance due to constitutional and unregulated expression of hEPO gene in the transgenic chicken. The latter is for maximum expression of the foreign gene when we turn-on the gene expression. A replication-defective Moloney murine leukemia virus (MoMLV)-based vectors packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected beneath the blastoderm of non-incubated chicken embryos (stage X). Out of 325 injected eggs, 28 chicks hatched after 21 days of incubation and 16 hatched chicks were found to express the hEPO gene delivered by the vector. The biological activity of the recombinant hEPO in transgenic chicken serum was comparable to its commercially available counterpart. The recombinant hEPO in transgenic chicken serum had N- and O-linked carbohydrate simillar to that produced from in vitro cultured cells transformed with hEPO gene.

Several cloned animals have been produced using somatic cell nuclear transfer (SCNT) and have interested in producing the transgenic cloned animals to date. But still its efficiency was low due to a number of reasons, such as sub-optimal culture condition, aberrant gene expression and nuclear reprogramming. The purpose of this study was to analyze gene expression pattern in in vitro fertilized (IVF) or SCNT pre-implantation embryos. IVF- or SCNT-embryos were cultured in media supplemented with different proteins (FBS and BSA) or energy sources (glucose or fructose). Blastocysts from IVF or SCNT were analyzed using semi-quantitative RT-PCR in terms of developmentor metabolic-related genes. Culture medium supplemented different proteins or energy sources had affected on the expression of developmental or metabolic genes in the SCNT blastocysts.

Many studies propose that dysfunction of mitochondrial proton-translocating NADH-ubiquinone oxidoreductase (complex I) is associated with neurodegenerative disorders, such as Parkinson's disease and Huntington's disease. Mammalian mitochondrial proton-translocating NADH-quinone oxidoreductase (complex I) consists of at least 46 different subunits. In contrast, the NDI1 gene of Saccharomyces cerevisiae is a single subunit rotenone-insensitive NADH-quinone oxidoreductase that is located on the matrix side of the inner mitochondrial membrane. With a recombinant adeno-associated virus vector carrying the NDI1 gene (rAAV-NDI1) as the gene delivery method, we were able to attain high transduction efficiencies even in the human epithelial cervical cancer cells that are difficult to transfect by lipofection or calcium phosphate precipitation methods. Using a rAAV-NDI1, we demonstrated that the Ndi1 enzyme is successfully expressed in HeLa cells. The expressed Ndi1 enzyme was recognized to be localized in mitochondria by confocal immunofluorescence microscopic analyses and immunoblotting. Using digitonin-permeabilized cells, it was shown that the NADH oxidase activity of the NDI1-transduced HeLa cells were not affected by rotenone which is inhibitor of complex I, but was inhibited by flavone and antimycin A. The NDI1-transduced cells were able to grow in media containing rotenone. In contrast, control cells that did not receive the NDI1 gene failed to survive. In particular, in the NDI1-transduced cells, the yeast enzyme becomes integrated into the human respiratory chain. It is concluded that the NDI1 gene provides a potentially useful tool for gene therapy of mitochondrial diseases caused by complex I deficiency.