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Genetic transformation of host plants by Agrobacterium tumefaciens and related species represents a unique model for natural horizontal gene transfer. Almost five decades of studying the molecular interactions between Agrobacterium and its host cells have yielded countless fundamental insights into bacterial and plant biology, even though several steps of the DNA transfer process remain poorly understood. Agrobacterium spp. may utilize different pathways for transferring DNA, which likely reflects the very wide host range of Agrobacterium. Furthermore, closely related bacterial species, such as rhizobia, are able to transfer DNA to host plant cells when they are provided with Agrobacterium DNA transfer machinery and T-DNA. Homologs of Agrobacterium virulence genes are found in many bacterial genomes, but only one non- Agrobacterium bacterial strain, Rhizobium etli CFN42, harbors a complete set of virulence genes and can mediate plant genetic transformation when carrying a T-DNA-containing plasmid.
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CRISPR RNA ‐guided integrase enables high‐efficiency targeted genome engineering in Agrobacterium tumefaciens
Summary Agrobacterium tumefaciens, the causal agent of plant crown gall disease, has been widely used to genetically transform many plant species. The inter‐kingdom gene transfer capability madeAgrobacteriuman essential tool and model system to study the mechanism of exporting and integrating a segment of bacterial DNA into the plant genome. However, many biological processes such asAgrobacterium‐host recognition and interaction are still elusive. To accelerate the understanding of this important plant pathogen and further improve its capacity in plant genetic engineering, we adopted a CRISPR RNA‐guided integrase system forAgrobacteriumgenome engineering. In this work, we demonstrate thatINsertion ofTransposableElements byGuideRNA–AssistedTargEting (INTEGRATE) can efficiently generate DNA insertions to enable targeted gene knockouts. In addition, in conjunction with Cre‐loxPrecombination system, we achieved precise deletions of large DNA fragments. This work provides new genetic engineering strategies forAgrobacteriumspecies and their gene functional analyses.
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- PAR ID:
- 10371763
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Plant Biotechnology Journal
- Volume:
- 20
- Issue:
- 10
- ISSN:
- 1467-7644
- Page Range / eLocation ID:
- p. 1916-1927
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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