Drought-tolerant, insect-resistant maize

The drought-tolerant, insect-resistant maize (MON 87460 × MON 89034) was obtained through crossing the two maize event products: MON 87460 and MON 89034. The modified maize expresses Bacillus subtilis cold shock protein (from MON97460), which confers cold and drought tolerance, as well as the Bacillus thuringiensis insecticidal proteins Cry1A.105 and Cry2Ab2 (from MON 89034), which confer resistance to Lepidoptera pests. Additionally, a selectable marker for kanamycin resistance (neomycin phosphotransferase II) is expected to be present as it was used for selection of transformants during the generation of the parental MON 87460 line.

PV-ZMAP595; PV-ZMIR245

Genetic elements introduced from PV-ZMAP595
Two gene cassettes were integrated from this vector.
I. Transcription of Bacillus subtilis cold shock protein (CspB) begins from the Oryza sativa (rice) actin 1 promoter and ends at the Agrobacterium tumefaciens 3' untranslated region of transcript 7. Transcript contains the rice actin 1 intron at the 5' end. The intron is expected to enhance gene expression of CspB.

II. Transcription of the Escherichia coli neomycin phosphotransferase II (nptII) is under the control of the Cauliflower Mosaic Virus (CaMV) 35S promoter and the A. tumefaciens nopaline synthase terminator (nos). The gene cassette is flanked by Bacteriophage P1 locus of cross-over P1 (loxP) sites.

Please note
- The parental line contains a single insertion of the T-DNA from this vector.
- No vector backbone sequence was detected.
- The parental line contains intact genetic cassettes.

Genetic elements introduced from PV-ZMIR245
Two gene cassettes were present in the parental line.
III. Transcription of the Bacillus thuringiensis crystal 1A.105 (Cry1A.105) is commences from the CaMV enhanced 35S promoter and terminates at the Triticum aestivum (wheat) heat shock protein 17.3 terminator. The transcript contains a rice actin 1 intron and a wheat chlorophyll a/b-binding protein 5' leader  for enhanced gene expression.

IV. Transcription of B. thuringiensis Cry2Ab2 is under the control of the Figwort Mosaic Virus 35S promoter and the A. tumefaciens nos terminator. Zea mays heat shock protein 70 intron and transit peptide form Rubisco small subunit are also present in the transcript at the 5' end for enhanced gene expression and chloroplast targeting, respectively.

Please note
- The Cry2Ab2 coding sequence was optimized for expression in plants.
- An additional nptII cassette in reverse orientation was present in the pV-ZMIR245 vector and inserted as a secondary, unlinked T-DNA. During the development of the parental line, selective breeding was done to remove the nptII marker, resulting in a marker-free parental line.
- Southern blot analysis confirmed a single insertion and expression of the other T-DNA containing the genetic cassettes mentioned above (III and IV).
- DNA sequencing indicated that enhanced CaMV promoter did not contain the duplicated enhancer regions.
- No vector backbone was detected in the parental line.

For more information, kindly refer to the parental modified organism records