Genome editing in plants using CRISPR type I-D nuclease.

Area of Science:

• Plant biotechnology
• Molecular biology
• Genome engineering

Background:

• CRISPR-Cas9 is widely used for plant genome editing.
• CRISPR Type I systems, abundant in bacteria, remain largely unexploited in plants.
• Existing Type I systems often utilize Cas3 nucleases for DNA degradation.

Purpose of the Study:

• To introduce and characterize a Type I-D (TiD) CRISPR-Cas system for plant genome editing.
• To investigate the unique editing capabilities of the TiD system in plants.
• To assess the efficiency of TiD in generating specific mutation types and bi-allelic mutants.

Main Methods:

• Development and application of a Type I-D CRISPR-Cas system in tomato.
• Targeted mutagenesis using the TiD system.
• Analysis of mutation types (indels, long deletions) and bi-allelic mutant generation.

Main Results:

• The TiD system demonstrated activity in targeted mutagenesis of tomato genomic DNA.
• TiD generated distinct mutations compared to CRISPR-Cas9, including bi-directional long-range deletions and short indels.
• Efficient generation of bi-allelic mutant plants was achieved in the first generation using TiD.

Conclusions:

• The Type I-D CRISPR-Cas system (TiD) is a novel and functional genome editing tool for plants.
• TiD offers unique editing capabilities, producing different mutation profiles than CRISPR-Cas9.
• TiD provides an efficient method for generating bi-allelic mutants, advancing plant genome engineering.