New Leaf™ Russet Burbank potato

Colorado potato beetle resistant potatoes produced by inserting the cry3A gene from Bacillus thuringiensis. The neomycin phosphotransferase II (npt II) gene confers resistance to the antibiotic kanamycin is used as a selection marker.

Cultivar: Russet Burbank

PV-STBT02

The coding sequence of the Cry3A gene was modified to plant preferred codons. This resulted in changes to 399 of 1791 nucleotides but there were no changes to the resulting amino acid sequence.

Southern blot analysis indicated that a two copies of the transformation cassette were integrated into the host genome at two independent sites with no detectable rearrangements, insertions or segments of the vector backbone.

Cry proteins, of which Cry3A is only one, act by selectively binding to specific sites localized on the lining of the midgut of susceptible insect species. Following binding, pores are formed that disrupt midgut ion flow causing gut paralysis and eventual death due to bacterial sepsis. Cry3A is insecticidal only when eaten by the larvae of coleopteran insects such as Colorado potato beetle and its specificity of action is directly attributable to the presence of specific binding sites in the target insects.