Maize modified for herbicide tolerance and insect resistance

MON-87411-9 maize was modified to contain a suppression cassette that expresses an inverted repeat sequence designed to match the sequence of western corn rootworm (WCR).

The expression of the suppression cassette results in the formation of a double-stranded RNA (dsRNA) transcript containing a 240 bp fragment of the WCR Snf7 gene (DvSnf7). Upon consumption, the plant-produced dsRNA in MON 87411 is recognized by the CRW's RNA interference (RNAi) machinery resulting in down regulation of the targeted DvSnf7 gene leading to CRW mortality.

MON 87411 also contains a cry3Bb1 gene that produces a modified Bacillus thuringiensis (subsp. kumamotoensis) Cry3Bb1 protein to protect against CRW larval feeding.

In addition, MON 87411 contains the cp4 epsps gene from Agrobacterium sp. strain CP4 that encodes for the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) protein, which confers tolerance to glyphosate

PV-ZMIR10871

The DvSnf7p sequence is the partial coding sequence of the Snf7 gene from Diabrotica virgifera virgifera encoding the SNF7 subunit of the ESCRT-III complex. The DvSnf7 suppression cassette contains two 240 bp DvSnf7p sequences in an inverted orientation. There is an intervening sequence of 150 nucleotides between the two DvSnf7p sequences. When the suppression cassette is transcribed, the RNA expressed forms a hairpin loop thereby allowing the formation of double stranded DvSnf7 RNA. The DvSnf7p sequences in the suppression cassette produce a 240 bp dsRNA that upon transcription triggers the RNAi mechanism.

Sequencing, PCR, and bioinformatic analysis indicated that a single, intact insert of the DvSnf7 suppression cassette and the cry3Bb1 and cp4 epsps expression cassettes were stably integrated into the maize genome. Analyses also indicated the absence of the plasmid backbone DNA in MON 87411 maize.