Chloroplast Engineering of Herbicide Resistance

Through plastid genome engineering, we have achieved agronomic transformation of many important crops, such as herbicide resistance, drought tolerance, salt tolerance, insect resistance, pathogen resistance, nitrogen fixation, nutrition, and cytoplasmic male sterility. Here, Lifeasible is committed to providing reliable and economical solutions for the genetic engineering of chloroplast genomes to control herbicide resistance.

Introduction

Weeds have caused serious loss of quality and quantity of crops. Weed control is therefore essential to ensure adequate food for a rapidly growing population. A herbicide is a chemical that can interfere with the normal metabolic processes of plants and cause weeds to die. Compounds that are active against a broad range of weeds but ineffective against target crops have traditionally been screened for new compounds. However, herbicides don't just destroy weeds, they can also affect crops. Therefore, there is a need to develop herbicide resistance in crop varieties as well as improve other important agronomic traits, which can increase crop yields and help farmers manage weeds. In plants, resistance may occur naturally or may be induced by techniques such as genetic engineering or selection of variants generated by tissue culture or mutagenesis.

Fig. 1. Use of genome editing for the development of herbicide resistance in plants. (Hussain A, et al., 2021)

Our Solutions

Most herbicides target specific enzymes involved in metabolic pathways critical to plant growth and survival, affecting chloroplast function through chloroplast targets. Our engineers have attempted to genetically engineer these target sites through chloroplasts for herbicide resistance. Here, we provide the following two strategies to provide solutions for chloroplast engineering of herbicide-resistant plants.

(1) Chloroplast Engineering for Herbicide Resistance via Herbicide-Insensitive Enzymes

We inserted the encoded enzymes of the target of herbicides in plant chloroplasts into the chloroplast genome to make transgenic plants insensitive to herbicides, or induce excessive production of unmodified target proteins, so that they can be metabolized normally even in the presence of herbicides. Enzyme targets that we can achieve include, but are not limited to:

• Enolpyruvylshikimatephosphate Synthase (EPSPS)
• Acetolactate Synthase (ALS)
• Glutamine Synthetase (GS)
• Acetyl Co-A Carboxylase (ACCase)
• Photosynthesis Proteins
• Protoporphyrinogen Oxidase (PPO)
• Phytoene Desaturase (PDS)

(2) Chloroplast Engineering for Herbicide Resistance via Metabolic Detoxification

We introduced the expression of enzymes (bacterial detoxification enzymes and plant detoxification enzymes) that actively break down herbicides into the plant chloroplast genome to confer resistance to a variety of herbicides in crops.

Attractive Advantages of Our Solutions

• Herbicide resistance is conferred by target amplification.
• Chloroplast-expressed transgenes do not encounter gene silencing and have no deleterious effect on plant phenotype.
• Achieving rapid detoxification of herbicides.
• Low levels of gene expression can also demonstrate field-level tolerance to herbicides.
• Providing heritable, targeted modifications.
• Multiple amino acid substitutions of target genes that provide resistance to multiple herbicides.
• Saving time and cost in herbicide resistance development.
• No risk assessment is required for herbicide-resistant crops without the introduction of foreign DNA.

Lifeasible's goal is to provide customers around the world with fully customized chloroplast engineered solutions for herbicide resistance. It should be pointed out that we only provide solutions for the development of herbicide resistance in crops, and do not produce herbicides that can be used directly. Please contact us to discuss further details to ensure your next success.

References

1. Hussain A, Ding X, Alariqi M, et al. (2021) Herbicide resistance: another hot agronomic trait for plant genome editing[J]. Plants. 10(4): 621.
2. Dhingra A, Daniell H. Engineering herbicide resistance pathways in plastids[M]//Molecular biology and biotechnology of plant organelles. Springer, Dordrecht, 2004: 491-511.