关键词: 诱导表达, GUS活性, pib启动子, 水稻

Abstract: A 5.7kb putative promoter region of pib gene was isolated from the pib genomic clone and substituted the 35S promoter upstream of gus gene in plasmid pCAMBIA1301 to construct a new gus expression vector pNAR604 (putative pib promoter-GUS+35S-hpt). From Agrobecteria mediate transformation and hygromycin selective culture in vitro, hygromycin resistant calli and 36 transgenic rice plants were obtained. Histochemical assays of GUS gene showed those resistant callus and roots from transgenic plants cultured under light were no blue-stained with X-gluc, but callus and roots after 24 h treatment of darknees and then incubated with X-gluc could present blue. Fluorimetric enzyme quantitative analyses indicated GUS expression in transgenic plants was organ specificity. Without darknees treatment, GUS activity of root and stem was as higher as 7 and 3 times than leaf and GUS activity in leaf was only trace detected. After 24 h darkness treatment, GUS activity in root, stem, leaf of transgenic plants were all increased and highest increase was in leaf but active volume of root was still highest in the three. 24 h after spray with 5 mmol/L SA or 0.3 mol/L NaCl, GUS activity in leaf of transgenic plants would be as higher as 2.7 or 3.6 times than before spray. It was confirmed that an inductive promoter was involved in this 5.7 kb upstream region of pib gene. Darkness，SA and NaCl were inductive factors for pib romoter.