Comparative study on effect of different promoters on expression of cry1Ac in Bacillus thuringiensis chromosome.
OBJECTIVE
The aim of this work was to investigate the effect of cry3A promoter on the expression of cry1Ac in Bacillus thuringiensis chromosome and stably enhance the production of different cry genes under the control of cry3A promoter.


RESULTS
The cry1Ac gene, which is specific to Lepidopteran larvae, was integrated into the chromosome of a B. thuringiensis plasmid-free and acrystalliferous strain BMB171, under the control of cry3A promoter and cry1Ac promoter, respectively. The expression of cry1Ac genes in the chromosome of host strain was investigated. The results from sodium dodecyl sulfate-polyacrymide gel electrophoresis, crystal observation and bioassay showed that either integrated with cry3A promoter (cry3Apro-cry1Ac) or with its native promoter (cry1Acpro-cry1Ac), cry1Ac gene could efficiently and stably express in the chromosome. The production of cry3Apro-cry1Ac gene was higher than that of cry1Acpro-cry1Ac gene.


CONCLUSIONS
The cry3A promoter enhanced the expression of cry1Ac gene efficiently either on the chromosome or on the plasmid in B. thuringiensis strain.


CONCLUSIONS
So far, the comparative studies on cry3A promoter and other cry promoters were carried on B. thuringiensis plasmids. This system offers an additional method for potentially improving the efficacy of B. thuringiensis insecticidal proteins efficiently, stably and safely.
Chaoyin
Y
Y
Biotechnology Research Center, China Three Gorges University, Yichang, Hubei, China. yuechaoyin@163.com
Wei
S
S
Sun
M
M
Lin
L
L
Faju
C
C
Zhengquan
H
H
Ziniu
Y
Y
D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics* / Q000648:ultrastructure; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000494:pharmacology; D001427:Bacterial Toxins / Q000235:genetics* / Q000494:pharmacology; D002876:Chromosomes, Bacterial / Q000235:genetics*; D003470:Culture Media; D004269:DNA, Bacterial / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004731:Endotoxins / Q000235:genetics* / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D005822:Genetic Vectors / Q000235:genetics; D042822:Genomic Instability / Q000235:genetics; D006460:Hemolysin Proteins / Q000235:genetics* / Q000494:pharmacology; D007306:Insecticides / Q000494:pharmacology; D007915:Lepidoptera / Q000187:drug effects; D008854:Microscopy, Electron / Q000379:methods; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003470:Culture Media; D004269:DNA, Bacterial; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis