Development of intron-containing barnase gene (barnase-int) encoding a toxic protein to facilitate its cloning in bacterial cells

摘要

Developing gene constructs with the barnase gene and propagating them in Escherichia coli or Agrobacterium tumefaciens is difficult as unintended leaky expression leads to the death of the bacterial cells. In the present work, we circumvented this problem by developing intron containing barnase genes. We tested the use of two different introns viz., (i) the first intron (190 bp) of the catalase gene of castor bean and (ii) the twelfth intron (92 bp) of Pyruvate ortho-phosphate dikinase 2 (PPDK2) gene from cotton. Due to the absence of splicing in bacterial cells the unintended expression of the barnase protein was blocked allowing easy development and propagation of constructs. Further, we demonstrated that the intron introduced in the barnase gene was efficiently spliced out in the tapetum tissue of the anther in transgenic tobacco lines leading to male-sterility