Identiifcation of similar transcriptional regulatory mechanisms in multiplecry genes inBacillus thuringiensis HD12

• Published in: 农业科学学报（英文） Vol. 16; no. 1; pp. 135 - 143
• Main Authors: SONG Zhi-ru, PENG Qi, SHU Chang-long, ZHANG Jie, SUN Dong-mei, SONG Fu-ping
• Format: Journal Article
• Language: English
• Published: Colege of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing 163319, P.R.China%State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, P.R.China 2017
• Subjects: Bacilus thuringiensis; transcription; insecticide; cry genes
• ISSN: 2095-3119
• DOI: 10.1016/S2095-3119(16)61398-9

Bacilus thuringiensissubspeciesmorrisoni strain HD12, whose genome harbors multiple insecticidal protein-encoding genes, includes eightcry genes, as indicated by genome sequencing. This strain produces crystals that are toxic to lepidopteran species. These crystal inclusions were puriifed by sucrose gradients and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), folowed by liquid chromatography-mass spectrometry, and found to contain ifve proteins (Cry1Da, Cry1Ae, Cry1Bb, Cry1Fb, and Cry1Ja). The transcriptional activities of thecry1Da,cry1Ae,cry1Bb, cry1Fb,and cry1Japromoters indicated that transcription ofcry1Da is controled by SigE; however, the other fourcry genes were found to be controled by both SigE and SigK. The activities of thecry1Ja andcry1Fb promoters were the strongest among the ifve genes studied. These promoters were therefore used to direct the expression of the Cry1Ac- and Cry2Ab-encoding genes concurrently in a single strain. Our ifndings indicate that promoters with the same transcriptional proifle may be used to direct the expression of differentcry genes in one strain. Our results are expected to be valuable for the construction of strains with efifcient expression of multiplecry genes in order to overcome current limitations associated with the application ofB. thuringiensis-based insecticides.