Maize modified for tissue selective glyphosate tolerance

MON87427 was modifies to express the CP4 EPSPS protein which confers tolerance to the herbicide glyphosate.

The e35S-hsp70 promoter and intron combination is used to drive the tissue selective expression of the cp4 epsps gene resulting in CP4 EPSPS protein production in vegetative and female reproductive tissue, providing tolerance to glyphosate within these tissues. This specific promoter and intron combination also results in limited or no production of CP4 EPSPS protein in two key male reproductive tissues: pollen microspores which develop into pollen grains, and tapetum cells that supply nutrients to the pollen.

Thus, in MON 87427, male reproductive tissues critical for male gametophyte development are not tolerant to glyphosate. This allows glyphosate-treated MON 87427 containing inbred lines to serve as a female parent in the production of hybrid seed.

Cultivar: LH198 × HiII

PV-ZMAP1043

The cp4 epsps coding sequence is the codon optimized coding sequence of the aroA gene from Agrobacterium sp. strain CP4 encoding CP4 EPSPS.

Southern blot analyses indicate that a single copy of the T-DNA was inserted at a single site in the maize genome and no plasmid vector backbone sequences were detected to have been integrated. DNA sequencing analyses indicated that the expected T-DNA sequences were integrated.