Fig. 8.

Effect of the 3’-untranslated region (3’-UTR) of the cyt1Aa gene on synthesis of Cyt1Aa in B. thuringiensis. A. Putative stem-loop structures formed at the 3’-ends of cyt1Aa and cry11Aa mRNAs, with a predicted ΔG value of -27.6 and -17.2 kcal as determined by the method of Tinoco et al. (Ge, 1999). B. Constructs used to test the effect of 3’-flanking regions of the cyt1Aa gene on the production of Cyt1Aa proteins in B. thuringiensis by replacing the cyt1Aa terminator with cry11Aa terminator. Plasmid pSFCYT, cyt1Aa gene lacking its terminator; pSF123, cyt1Aa gene with its own terminator and pSFCYT-11SL, cyt1Aa gene with native terminator replaced with the terminator from the cry11As gene. C. SDS-12% PAGE analysis of the relative level of Cyt1Aa proteins from the same volume of B. thuringiensis 4Q7 cell cultures with different constructs. Lane M, protein marker; lane 1, the strain harboring plasmid that has cyt1Aa with its own 3’ termination sequence [pSF123]; lane 2, the strain harboring plasmid that has cry11Aa without its own 3’ termination sequence [pSFCYT]; lane 3, the strain harboring plasmid that has cyt1Aa with the cry11Aa 3’ termination sequence [pSFCYT-11SL]. The rations at the bottom of the lanes were determined by densitometry scanning of the gel.