Dataset Information

Whole-genome analysis of herbicide-tolerant mutant rice generated by Agrobacterium-mediated gene targeting.

ABSTRACT: Gene targeting (GT) is a technique used to modify endogenous genes in target genomes precisely via homologous recombination (HR). Although GT plants are produced using genetic transformation techniques, if the difference between the endogenous and the modified gene is limited to point mutations, GT crops can be considered equivalent to non-genetically modified mutant crops generated by conventional mutagenesis techniques. However, it is difficult to guarantee the non-incorporation of DNA fragments from Agrobacterium in GT plants created by Agrobacterium-mediated GT despite screening with conventional Southern blot and/or PCR techniques. Here, we report a comprehensive analysis of herbicide-tolerant rice plants generated by inducing point mutations in the rice ALS gene via Agrobacterium-mediated GT. We performed genome comparative genomic hybridization (CGH) array analysis and whole-genome sequencing to evaluate the molecular composition of GT rice plants. Thus far, no integration of Agrobacterium-derived DNA fragments has been detected in GT rice plants. However, >1,000 single nucleotide polymorphisms (SNPs) and insertion/deletion (InDels) were found in GT plants. Among these mutations, 20-100 variants might have some effect on expression levels and/or protein function. Information about additive mutations should be useful in clearing out unwanted mutations by backcrossing.

SUBMITTER: Endo M

PROVIDER: S-EPMC4301741 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Whole-genome analysis of herbicide-tolerant mutant rice generated by Agrobacterium-mediated gene targeting.

Endo Masaki M Kumagai Masahiko M Motoyama Ritsuko R Sasaki-Yamagata Harumi H Mori-Hosokawa Satomi S Hamada Masao M Kanamori Hiroyuki H Nagamura Yoshiaki Y Katayose Yuichi Y Itoh Takeshi T Toki Seiichi S

Plant & cell physiology 20141104 1

Gene targeting (GT) is a technique used to modify endogenous genes in target genomes precisely via homologous recombination (HR). Although GT plants are produced using genetic transformation techniques, if the difference between the endogenous and the modified gene is limited to point mutations, GT crops can be considered equivalent to non-genetically modified mutant crops generated by conventional mutagenesis techniques. However, it is difficult to guarantee the non-incorporation of DNA fragmen ...[more]

PMID: 25378689

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Dataset Information

Whole-genome analysis of herbicide-tolerant mutant rice generated by Agrobacterium-mediated gene targeting.

Publications

Whole-genome analysis of herbicide-tolerant mutant rice generated by Agrobacterium-mediated gene targeting.

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