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Plant transformation has enabled fundamental insights into plant biology and revolutionized commercial agriculture. Unfortunately, for most crops, transformation and regeneration remain arduous even after more than thirty years of technological advances. Genome editing provides new opportunities to enhance crop productivity, but relies on genetic transformation and plant regeneration, which are bottlenecks in the process. Herein we review the state of plant transformation and point to innovations needed to enable genome editing in crops. Plant tissue culture methods need optimization and simplification for efficiency and minimize time in culture. Currently, specialized facilities exist for crop transformation. Single cell and robotic techniques should be developed for high throughput genomic screens. Utilization of plant genes involved in developmental reprogramming, wound response, and/or homologous recombination could boost recovery of transformed plants. Engineering universal Agrobacterium strains and recruitment of other microbes, such as Ensifer or Rhizobium, could facilitate delivery of DNA and proteins into plant cells. Synthetic biology should be employed for de novo design of transformation systems. Genome editing is a potential game-changer in crop genetics when plant transformation systems are optimized.
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Unlocking regeneration potential: harnessing morphogenic regulators and small peptides for enhanced plant engineering
SUMMARY Plant genetic transformation is essential for understanding gene functions and developing improved crop varieties. Traditional methods, often genotype‐dependent, are limited by plants' recalcitrance to gene delivery and low regeneration capacity. To overcome these limitations, new approaches have emerged that greatly improve efficiency and genotype flexibility. This review summarizes key strategies recently developed for plant transformation, focusing on groundbreaking technologies enhancing explant‐ and genotype flexibility. It covers the use of morphogenic regulators (MRs), stem cell‐based methods, andin plantatransformation methods. MRs, such as maizeBabyboom(BBM) withWuschel2(WUS2), andGROWTH‐REGULATING FACTORs(GRFs) with their cofactorsGRF‐interacting factors(GIFs), offer great potential for transforming many monocot species, including major cereal crops. OptimizingBBM/WUS2expression cassettes has further enabled successful transformation and gene editing using seedling leaves as starting material. This technology lowers the barriers for academic laboratories to adopt monocot transformation systems. For dicot plants, tissue culture‐free orin plantatransformation methods, with or without the use of MRs, are emerging as more genotype‐flexible alternatives to traditional tissue culture‐based transformation systems. Additionally, the discovery of the local wound signal peptide Regeneration Factor 1 (REF1) has been shown to enhance transformation efficiency by activating wound‐induced regeneration pathways in both monocot and dicot plants. Future research may combine these advances to develop truly genotype‐independent transformation methods.
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- Award ID(s):
- 1917138
- PAR ID:
- 10559672
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 121
- Issue:
- 2
- ISSN:
- 0960-7412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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