An efficient transformation system for sugarbeet mediated by Agrobacterium tumefaciens

This paper describes the development of a reliable transformation protocol for sugarbeet which can be used for integration of foreign gene into plant genome. To optimize a transformation protocol for sugarbeet with Agrobacterium, bacterial strain LB4404 and a plasmid PBI121 containing kanamycin resistance and GUS genes were used in the transformation experiments. The influence of plant explants and amount of kanamycin added to selective medium were examined for their effect on transformation frequency. Among the different concentrations of kanamycin used, 100 mg/l was the optimum for both transformation frequency and survival of plant tissues. Leaf tissues showed high transformation frequency compared with shoot base explant. Transient expression of GUS in transformed cultures was assayed and large regions showed expression of GUS (blue patches). Polymerase Chain Reaction (PCR) was used to verify the presence of the transgenes in the selected cultures of sugarbeet. PCR analysis showed that high frequency of GUS positive cultures contained transgenes. The transformants were successfully developed to complete plants growing in freeliving conditions

Ginger ingredients inhibit the development of diethylnitrosoamine induced premalignant phenotype in rat chemical hepatocarcinogenesis model

To investigate the possible antitumor activity of ginger extract against hepatic carcinogenesis initiated by diethylnitrosoamines (DEN) and promoted by carbon tetrachloride (CCl4). A total of 60 mate Wistar albino rats were divided into four groups with 15 animals in each group. Rats in group 1 (control group) received a single intraperitoneal (i.p.) injection of normal saline. Animals in group 2 were given ginger (50 mg/kg/day) in drinking water for 8 weeks. Rats in group 3 (DEN group) were injected with a single dose of DEN (200 mg/kg, i.p.), 2 weeks later received a single dose of CCl4 (2 mL/kg i.g) by gavage as 1:1 dilution in corn oil. Animals in group 4 (DEN-ginger group) received the same carcinogenesis induction protocol as in group 3 plus ginger (50 mg/kg/day) in drinking water for 2 weeks before induction of hepatocarcinogenesis and continued throughout the experimental period. DEN-initiated and CCl4-promoted hepatocarcinogenesis in male Wistar rats was manifested biochemically by elevation of serum hepatic tumor markers tested; alpha-fetoprotein and carcinoembryonic antigen. In addition, hepatocarcinogenesis was further confirmed by a significant increase in hepatic tissue growth factors; vascular endothelial growth factor, basic fibroblast growth factor, and hydroxyproline content. A marked decrease in endostatin and metallothonein were also observed. Long-term ginger extract administration 2 weeks before induction of hepatocarcinogenesis and throughout the experimental period prevented the decrease of the hepatic content of metallothionein and endostatin and the increase in the growth factors induced by the carcinogen. Moreover, ginger extract normalize serum hepatic tumor markers. Histopathological examination of liver tissue also correlated with the biochemical observations. These findings suggest a protective effect of ginger extract against premalignant stages of liver cancer in the DEN-initiated and CCl4-promoted hepatocarcinogenesis model in rats. (C) 2010 International Union of Biochemistry and Molecular Biology, Inc. Volume 36, Number 6, November/December 2010, Pages 483-490. E-mail: [email protected]