Cloning and expression of human vascular endothelial growth factor gene and inhibition of its expression by antisense in prokaryotic system.

BACKGROUND AND THE PURPOSE OF THE STUDY: Angiogenesis is an important process in physiology and disease pathogenesis and is controlled in a healthy body by a number of stimulatory and inhibitory factors. The aim of this study was to determine the effect of antisense transcript on the sense transcript of the endothelial growth factor (EGF) gene in bacterial system as an approach for the gene regulation in tumors. METHODS: The hepatoma cell line (HepG2) was stimulated by PMA. VEGF mRNA was used for RT-PCR. VEGF cDNA was synthesised and cloned into T-vector pTZ57R, then sense fragment of VEGF subcloned into pACYC Duet-1 expression vector and antisense VEGF subcloned into pCDNA3 expression vector. Recombinant plasmids were transforemed into BL21 bacterial cells. Expression of recombinant plasmid was analysed by western blot technique. RESULTS: The recombinant pCDNA3-VEGF (pYZantiVEGF) was successfully expressed in BL21 cells. Western blot analysis showed that the expression of VEGF decreased significantly in the cells transfected with VEGF antisense RNA compared with the pACYCDUET-1-VEGF (pYZsenseVEGF) transfected and control. MAJOR CONCLUSIONS: The expression of VEGF in BL21 cells was strong. In vitro, antisense of VEGF inhibited VEGF expression significantly in BL21 cells.

Non-radioactive labeled probe preparation for hbs gene detection.

Among some Bacillus species, a protein highly homologous to HU, classified HB and coded by hbs gene. According to the recent studies, the sequence of hbs gene just in one strain of Bacillus subtilis exists in gene bank (ATCC 23857). In this study, DNA from Bacillus subtilis ATCC 6633 was extracted and investigated by PCR. The PCR product was sequenced and shown to differ in just one nucleotide from B. subtilis ATCC 23857. Hence, it was chosen as reference and for the first time, used for non-radioactive labeled probe preparation. The PCR product in Bacillus subtilis with ATCC 6633 was labeled using non-radioactive DIG-labeled nucleotides and conditions of probe preparation and hybridization were optimized and checked it by Southern blotting.