GENTECH archive


Bt toxin, archive 444

Edo Lin's reply (archive 442) was more precise than that of Cummins. An
existing promoter widely used in maize, "pepc" and NOT CamV, expresses
in the leaves and essentially not the grain
(<fontfamily><param>Times</param><bigger><bigger>Koziel, M. G. et al,
1993,  Field performance of elite transgenic maize plants expressing an
insecticidal protein gene derived from <italic>Bacillus thuringiensis, 
Bio/Technology</italic>, <bold>11</bold>,
194-200).</bigger></bigger></fontfamily> Thus, the statement "Also,
these Bt toxins are only present in plant foliage, not the grain" is
accurate for many cultivars of maize, which is overwhelmingly the major
food crop that has any Bt in it.