Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in China, which is mainly caused by hepatitis B virus (HBV) infection. The X gene product (HBx) of HBV has extensive trans-activating functions. HBx affects the signal transduction, apoptotic cell death and cell cycle through interaction with variety intracellular proteins in infected hepatocytes. In view of the importance of HBx in HBV replication and in hepatic cell functions, the role of HBx in HCC development has been attracting great attention.
Carcinoma, Hepatocellular ; pathology ; Hepatitis B virus ; genetics ; physiology ; Humans ; Liver Neoplasms ; pathology ; Trans-Activators ; genetics ; physiology ; Virus Replication ; physiology

In order to study function of NAC transcription in development, hormone regulation and the stress response of Salvia miltiorrhiza, the NAC transcription was cloned and analyzed. By retrieving cDNA database of S. miltiorrhiza hairy root one NAC unigene was found, then a full length of cDNA was cloned by designing specific primers and PCR amplifying. Using ORF finder it was found that the cDNA containing a NAC-AB conserved domain in N-terminal, so the cDNA was a NAC transcription factor, named as SmNAC1 (kF006346). Bioinformatics analysis showed that SmNAC1 had an open reading frame (ORF) of 591 bp encoding 196 amino acids. The calculated protein had isoelectric point (pI) of 4.36 with molecular weight about 21.66 kDa. The transcription level of SmNAC1 after dealing with yeast extract (YE) and silver ion (Ag+) in S. miltiorrhiza hairy root was markedly stimulated up regulating. It was 1.4 fold compared with the control after induction 2 h, and maintained 2.0 fold on 4-12 h after induction. SmNAC1 may participate in regulation of stress response of YE + Ag+.
Cloning, Molecular ; Computational Biology ; Phylogeny ; Plant Proteins ; genetics ; physiology ; Plant Roots ; chemistry ; Salvia miltiorrhiza ; chemistry ; genetics ; Trans-Activators ; genetics ; physiology

OBJECTIVETo investigate whether hepatitis B x protein (HBx) stimulates vascular endothelial growth factor (VEGF) through hypoxia inducible factor-1 (HIF-1 alpha) pathway.

METHODSTwo plasmids including pIRES-EGFP-HBx and pTK-Hyg were co-transfected to a hepatocellular carcinoma cell line SMMC-7721. With fluorescence-positive and fluorescence-negative hygromycin-resistant colonies selected, expressions of VEGF and HIF-1 alpha in protein or/and mRNA level were detected.

RESULTSFluorescence-positive cells were stably integrated with HBx, in which expression of HIF-1 alpha and VEGF were upregulated. Fluorescence-negative cells did not express HBx, VEGF or HIF-1 alpha.

CONCLUSIONHBx can activate VEGF through HIF-1 alpha pathway.

Cell Line, Tumor ; Gene Expression Regulation ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; Trans-Activators ; physiology ; Transcription Factors ; genetics ; physiology ; Vascular Endothelial Growth Factor A ; genetics ; physiology

The most important factor in the pathogenesis of biomaterial-associated Staphylococcal infections is the formation of bacterial biofilms. Biofilm formation was regulated or influenced by quorum sensing. One of the quorum sensing systems agr is genus specific which controls the expression of a series of toxins and virulence factors and the interaction with the innate immune system. New research indicates that the role of agr during infection is controversial. The research progress will play an important role in the development of novel antibacterial agents and management of device-related infection of Staphylococci.
Bacterial Proteins ; physiology ; Biocompatible Materials ; Biofilms ; growth & development ; Gene Expression Regulation, Bacterial ; Humans ; Signal Transduction ; genetics ; Staphylococcal Infections ; microbiology ; Staphylococcus ; genetics ; physiology ; Trans-Activators ; physiology

Confocal laser scanning microscopy was used to observe the spatio-temporal expression of the pathway-specific gene redD during S. coelicolor cell cultivation. The corresponding mutant S. coelicolor lyqRY1522 carrying redD::eyfp in the chromosome was constructed. The temporal expression results of the fusion protein during submerged cultivation demonstrated that expression of redD began in the transition phase, continuing through the exponential growth phase to the stationary phase, and reached maximum in the stationary phase. On the other hand, redD was expressed only in substrate mycelia during solid-state culture, while aerial mycelia remained essentially non-fluorescent throughout culture. Results demonstrated that the expression pattern of redD coincides with that of the biosynthesis of the antibiotics during culture, revealing a direct correlation between the spatio-temporal distribution of regulatory gene expression and second metabolism.
Anti-Bacterial Agents ; biosynthesis ; Bacterial Proteins ; genetics ; metabolism ; Gene Expression Profiling ; Gene Expression Regulation, Bacterial ; physiology ; Mutation ; Signal Transduction ; physiology ; Streptomyces coelicolor ; genetics ; metabolism ; Trans-Activators ; genetics ; metabolism

Hepatitis B virus MHBst and HBx fragments were amplified to construct eukaryotic expression vector pCDNA3.1-MHBst and pCDNA3.1-HBx. ST3GalI promoter region was obtained by the method of PCR and GFP report plasmid pEGFP-N1-Psial was constructed. pCDNA3.1-MHBst or pCDNA3.1-HBx with pEGFP-N1-Psial were transiently co-transfected into QGY-7701 cells using calcium phosphate-DNA co-precipitation, respectively. The expressions of Psial-directed GFP were analyzed by FAC-Scalibur. It was found that MHBst/HBx could upregulate ST3GalI promoter activity by 35.2% and 43.8%, respectively. We report the regulation of ST3GalI by MHBst and HBx transactivators. It would be helpful to further investigate the relation between hepatitis B virus infection and sialyltransferase expression.
Gene Expression Regulation, Enzymologic ; Hepatitis B Surface Antigens ; genetics ; physiology ; Hepatitis B virus ; Promoter Regions, Genetic ; Sialyltransferases ; genetics ; Trans-Activators ; genetics ; physiology ; Transfection

Animals ; Glucose ; pharmacology ; Homeodomain Proteins ; analysis ; genetics ; physiology ; Immunohistochemistry ; Insulin ; secretion ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Trans-Activators ; analysis ; genetics ; physiology

BACKGROUNDS/AIMS: Hepatitis B virus (HBV) replicates via RNA intermediates, which could serve as targets for RNA interference (RNAi). Vector-mediated short-hairpin RNA (shRNA) can induce sustained RNAi in comparison to small interfering RNA. Lentiviral vector is known to induce prolonged RNAi with high transduction efficiency. In this study, we sought to test the in vitro efficacy of shRNA delivered by a lentiviral vector in suppressing the replication of HBV. METHODS: Two shRNA sequences against the hepatitis B viral protein HBx (sh1580 and sh1685) were cloned downstream of the U6 promoter in an HIV-based plasmid to generate third-generation lentiviral vectors. HepAD38 cells were transduced with anti-HBx lentiviral vectors, and HBV replication was induced for 5 days. HBV DNA was isolated and quantified using real-time PCR. RESULTS: Lentiviral vectors encoding the shRNA against HBV transduced HepAD38 cells with high efficacy. The total intracellular HBV DNA content was significantly reduced by both sh1580 and sh1685 (2.9% and 12.0%, respectively; P<0.05). HBV covalently closed circular DNA (cccDNA) was also suppressed significantly (19.7% and 25.5%, respectively; P<0.05). CONCLUSIONS: Lentivirus-mediated delivery of shRNA against HBx can effectively suppress the replication of HBV and reduce HBV cccDNA in cell culture systems.
Cell Line, Tumor ; Genetic Vectors ; Hepatitis B virus/*genetics/growth & development/physiology ; Humans ; Lentivirus/*genetics ; *RNA Interference ; RNA, Viral/metabolism ; Trans-Activators/*antagonists & inhibitors/genetics/metabolism ; *Virus Replication

No abstract available.
Genetic Vectors ; Hepatitis B virus/*genetics/growth & development/physiology ; Humans ; Lentivirus/genetics ; *RNA Interference ; RNA, Viral/metabolism ; Trans-Activators/antagonists & inhibitors/genetics ; *Virus Replication

OBJECTIVETo explore the effect of a non-lethal heat shock, in comparison with the treatment of interferon-gamma (IFN gamma), on the expression of major histocompatibility complex transactivator (CTA) and its downstream target gene of the human leukocyte antigens (HLA)-DR in Jurkat cells.

METHODSThe changes of CTA mRNA in Jurkat cells before and after the treatment of heat shock or IFN gamma were detected using real time RT-PCR. The changes of CTA protein were detected with Western blot. The expression of HLA-DR was detected with flow cytometry. : CTA mRNA and protein were induced in Jurkat cells under heat shock, but not with IFN-gamma. The expression of HLA-DR gene significantly increased after recovery (P<0.01).

CONCLUSIONThe expressions of CTA and HLA-DR in Jurkat cells remarkably increase after heat shock, indicating that heat shock may help reconstruct relevant genes in cells with immunologic gene deficiencies.

HLA-DR Antigens ; metabolism ; Heat-Shock Response ; physiology ; Humans ; Jurkat Cells ; Nuclear Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; Trans-Activators ; genetics ; metabolism