GM Crop Database

Database Product Description

CV127-9 (BPS-CV127-9)
Host Organism
Glycine max (Soybean)
Trait
Imidazolinone herbicide tolerance.
Trait Introduction
Microparticle bombardment of plant cells or tissue
Proposed Use

Production for human consumption and livestock feed.

Product Developer
BASF Inc.

Summary of Regulatory Approvals

Country Food Feed Environment Notes
Argentina 2013 2013 2013
Australia 2012
Brazil 2009 2009 2009
Canada 2012 2012 2012
China 2013 2013
Colombia 2012 2011
European Union 2015 2015
Japan 2012 2013 2013
Korea 2013 2011
Malaysia 2013 2013
Mexico 2011 2011
New Zealand 2012
Paraguay 2014
Philippines 2010 2010
Russia 2012 2012
South Africa 2012 2012
Taiwan 2013
Turkey 2017
United States 2012 2012 2014
Uruguay 2014

Introduction Expand

CV127 soybean has been genetically modified to express an altered AtAHASL protein which is encoded by the csr1-2 gene from Arabidopsis thaliana and confers tolerance to imidazolinone herbicides. The AtAHASL protein encoded by csr1-2 is structurally and functionally identical to the native AtAHASL, except for substitution of a serine with an asparagine at residue 653 (S653N) which results in tolerance to imidazolinone herbicides. In addition, the csr1-2 gene in CV127 contains a second mutation, in which arginine at position 272 is replaced by lysine (R272K).

Summary of Introduced Genetic Elements Expand

Code Name Type Promoter, other Terminator Copies Form
csr1-2 acetohydroxyacid synthase large subunit HT native 5' and 3' untranslated regions 1

Characteristics of Glycine max (Soybean) Expand

Center of Origin Reproduction Toxins Allergenicity

Southeast Asia; wild soybean species endemic in China, Korea, Japan, Taiwan.

Self-polinated; rarely displays any dormancy characteristics; does not compete well with other cultivated plants.

Raw soybeans contain trypsin inhibitors, which are toxin when eaten.

Soy allergies are common, and eating soy products can cause rashes and swelling of the skin in sensitive individuals.

Modification Method Expand

A purified, linear DNA fragment derived from plasmid pAC321 was used to transform embryogenic axis tissue derived from the apical meristem of a single soybean seed of the commercial variety Conquista using particle bombardment. No carrier DNA was used in the process.

Soybean tissues were transformed with an approximately 6.2 kb linear fragment PvuII fragment derived from plasmid pAC321 containing the csr1-2 gene cassette.

The pAC321 fragment contains genomic Arabidopsis DNA including the mutant Arabidopsis acetohydroxyacid synthase large subunit (ahasl) coding sequence (also referred to in the literature as csr1-2) with transcription directed by the wild type Arabidopsis AHASL 5’ and 3’ untranslated regions (UTR) containing the putative promoter and terminator region. The csr1-2 coding sequence is 2013 bp long and includes the S653N point mutation which confers tolerance to imidazolinone herbicides. In addition to the S653N mutation, a second mutation was discovered in the Arabidopsis ahas coding sequence integrated in the CV127 soybean genome. This second mutation, in which arginine at position 272 of the AtAHAS protein is replaced by lysine, does not impact the enzymatic function of the AHAS enzyme or its herbicide tolerance properties.

Characteristics of the Modification Expand

The Introduced DNA:

The PvuII fragment derived from plasmid pAC321 was integrated at a single locus and as one single copy in the soybean genome. The complete CV127 insert sequence is 4758 bp in length.

No DNA sequences other than those derived from the PvuII transformation fragment were integrated into the CV127 genome. Southern blot analyses clearly indicated that no elements derived from the backbone of the plasmid pAC321 either linked or unlinked to the insert were detected in the genome of CV127. The insert in CV127 comprises a single functional copy of the csr1-2 gene as revealed by Southern blot analyses of and by cloning and sequencing of the insert, as well as genomic flanking DNA.

DNA sequence analysis revealed that the csr1-2 gene cassette contains three point mutations relative to the PvuII linear DNA fragment of pAC321. One of the point mutations is a G to A mutation at position 272 in the csr1-2 gene, which results in an amino acid change from arginine to lysine. This is a conservative amino acid substitution and has no impact on the herbicide tolerance or enzymatic properties of the AtAHAS protein. The other two mutations are genetically silent.

Sequence analysis revealed that parts of the PvuII transformation fragment are not contained within the transgene insert in CV127. Deletions of unannotated Arabidopsis genomic DNA occurred both at the 5’ end and 3’ end during insertion into the soybean genome.

Stability and Inheritance:

The integration of one single insert into the nuclear soybean genome was confirmed by segregation data of the csr1-2 gene which showed that tolerance to the herbicide is conferred by a single gene and that this trait is inherited according to classical Mendelian genetics.

Protein Expression Levels:

Expression levels of the AHAS protein in different tissues of CV127 soybean plants were determined by enzyme-linked immunosorbent assay using AHAS-specific antibodies. Generally, expression levels of the AtAHASL protein in CV127 soybean are extremely low, especially at later stages of plant growth and development. AHAS enzyme activity is highest in young and growing plant tissues (leaves and whole plants at the V2 growth stage) where the need for branched chain and other amino acids is greatest due to the higher level of de novo protein synthesis and declines as tissues mature. Expression of AHAS decreased with age of the plant and AHAS was only barely detectable or undetectable in roots, older leaves, and grain.

Links to Further Information Expand

Argentina Secretariat of Agriculture, Livestock and Fisheries COGEM - The Netherlands Comissão Técnica Nacional de Biossegurança - CTNBio (Brazil) European Food Safety Authority European Food Safety Authority (EFSA) Food Standards Australia/New Zealand (FSANZ) Health Canada ICA Colombian Agricultural Institute Japan Food Safety Commission Korea Ministry of Food and Drug Safety Malaysia Ministry of Natural Resources and Environment Mexico Secretary of Health (COFEPRIS) Philippines Department of Agriculture US FDA Uruguay National Biosafety Cabinet

This record was last modified on Friday, August 11, 2017