What is a repositorium?

The repositorium is a searchable database that provides data on relevant articles from journals, company web pages and web pages of governmental agencies about studies/applications of genome-editing in model plants and agricultural crops in the period January 1996 to May 2018. Search options are article type, technique, plant, traits or free text. The repositorium is based on the systematic map of Dominik Modrzejewski et al., published in the journal environmental evidence. (Download article PDF).

Biallelic Gene Targeting in Rice

Typ / Jahr

Journal Article / 2016


Endo, Masaki; Mikami, Masafumi; Toki, Seiichi


Sequence-specific nucleases (SSNs) have been used successfully in homology-directed repair (HDR)-mediated gene targeting (GT) in many organisms. However, break-induced GT in plants remains challenging due to inefficient delivery of HDR templates and SSNs into plant nuclei. In many plants, including rice, Agrobacterium-mediated transformation is the most practical means of transformation because this biotic transformation system can deliver longer and more intact DNA payloads with less incorporation of fragmented DNA compared with physical transformation systems such as polyethylene glycol, electroporation, or biolistics. Following infection with Agrobacterium, transfer of transfer DNA (T-DNA) to the nucleus and its integration into the plant genome occur consecutively during cocultivation, thus timing the induction of DNA double-strand breaks (DSBs) on the target gene to coincide with the delivery of the HDR template is crucial. To synchronize DSB induction and delivery of the HDR template, we transformed a Cas9 expression construct and GT vector harboring the HDR template with guide RNAs (gRNAs) targeting the rice acetolactate synthase (ALS) gene either separately or sequentially into rice calli. When gRNAs targeting ALS were transcribed transiently from double-stranded T-DNA containing the HDR template, DSBs were induced in the ALS locus by the assembled Cas9/gRNA complex and homologous recombination was stimulated. Contrary to our expectations, there was no great difference in GT efficiency between Cas9-expressing and nonexpressing cells. However, when gRNA targeting DNA ligase 4 was transformed with Cas9 prior to the GT experiment, GT efficiency increased dramatically and more than one line exhibiting biallelic GT at the ALS locus was obtained.

Plant physiology
Periodical Number
Page range


ID Corresponding Author
Plant Species GE Technique
Sequence Identifier
Type of Alteration
Progress in Research
Key Topic
97 Toki, Seiichi
Oryza sativa CRISPR/Cas9
herbicide tolerance
Basic research
Basic research