The cry1Ac gene (truncated, 1857bp) was reconstructed by IIT,
Kharagpur for increased plant expression. The cry1Ac protein
present in Bt cotton contains the hyper variable region that has
been shown to be responsible for insecticidal specificity. The
cry1Ac gene cloned in pUC18 vector encodes truncated version of
native cry1Ac gene present in Bacillus thuringiensis. The truncated
toxin protein produced in Bt cotton is 100% identical in activity
to the naturally occurring cry1Ac protein.