Transforming Maize With Insect-resistant Gene And Expression Analysis

Corn is one of most important food crops in the world, Pest damage is the maincause yield losses of maize. Traditional breeding is time-consuming and lowefficiency，transgenic maize has become one of the most effective ways to solve pestdamage.The wild Bacillus thuringiensis Cry1F gene was modified according to plantpreferring codons, and the5’end preceded by a AdhI enhancer sequences. In orderto verify its toxicity to the corn borer and the other pests, modified Cry1Fgene wascloned into prokaryotic expression vector Pet28b, and then the vector transformedinto E. coli BL21(DE3) strain.The protein expression was confimed by SDS-PAGEand immune test paper. Collecting the induced soluble protein, added tothe artificial feeds, and feed corn borer. The result show that the modified Cry1F genecan express toxic protein, Cry1F gene engineered proved correct.Modified Cry1F gene had been cloned into plant expression vector CPB inwhich the gene was under the control of CaMV35S promoter. Bar gene as aselection marker gene. Cry1F gene was introdued into immature embryo callus usingparticle bombardment. After screening, regeneration, and get the transgenic plants.The transgenic plants were preliminary identified by PCR. Southern bolting assay forthe transgenic plants indicated that the Cry1F gene had been integrated into genomeof maize.The transgenic plants expressed toxic protein by immune test paper.Theresults of insect assay with corn borer showed that the transgenic maize showedinsectticdal activity against corn borer.After the wild type Cry1F gene was modified successfully, the transgenicmaize was obtained by gene gun mediated. Experiments showed that the transgenicmaize could highly expressed toxic protein and good insect resistance.