Genome editing using type I-E CRISPR-Cas3 in mice and rat zygotes.

The type I CRISPR system has recently emerged as a promising tool, especially for large-scale genomic modification, but its application to generate model animals by editing zygotes had not been established. In this study, we demonstrate genome editing in zygotes using the type I-E CRISPR-Cas3 system, which efficiently generates deletions of several thousand base pairs at targeted loci in mice with 40%-70% editing efficiency without off-target mutations. To overcome the difficulties associated with detecting the variable deletions, we used a newly long-read sequencing-based multiplex genotyping approach.

Transglutaminase-mediated proximity labeling of a specific Lys residue in a native IgG antibody.

The fusion protein of an engineered zymogen of microbial transglutaminase (EzMTG) with a protein G variant, EzMTG-pG, enabled the proximity-based, tag-free labeling of Lys65 in the heavy chain of a native IgG antibody (trastuzumab) with a Gln-donor peptidyl substrate functionalized with a fluorescent molecule.

A novel Kit mutant rat enables hematopoietic stem cell engraftment without irradiation.

Hematopoietic stem cell (HSC) transplantation is extensively studied in mouse models, but their limited scale presents challenges for effective engraftment and comprehensive evaluations. Rats, owing to their larger size and anatomical similarity to humans, offer a promising alternative. In this study, we establish a rat model with the Kit mutation, mirroring Kit mice often used in KIT signaling and HSC research.