A Recql5 mutant facilitates complex CRISPR/Cas9-mediated chromosomal engineering in mouse zygotes

Area of Science:

• Genetics and Genomics
• Molecular Biology
• Cancer Research

Background:

• Complex chromosomal rearrangements (CCRs) are prevalent in cancer and congenital diseases.
• Experimental induction of CCRs remains a significant challenge in research.
• Understanding the mechanisms underlying CCRs is crucial for disease pathology.

Purpose of the Study:

• To establish the first animal models for studying complex chromosomal rearrangements (CCRs).
• To investigate the role of Recql5 in facilitating CRISPR/Cas9-mediated CCRs.
• To provide a tool for analyzing the pathogenesis of CCRs, including chromoanasynthesis.

Main Methods:

• Utilized CRISPR/Cas9 technology for targeted genetic modification.
• Introduced mutations in the Recql5 gene, a DNA helicase involved in DNA repair.
• Established a mouse model exhibiting triple fusion genes and megabase-sized inversions.

Main Results:

• Successfully generated the first animal models for complex chromosomal rearrangements (CCRs).
• Demonstrated that Recql5 deficiency enables CRISPR/Cas9-mediated CCRs.
• Observed structural features in rearrangements consistent with template switching and microhomology-mediated break-induced replication, resembling chromoanasynthesis.

Conclusions:

• Recql5 mutant mice represent a powerful new tool for studying CCRs and chromoanasynthesis.
• These models will facilitate research into the poorly understood mechanisms of CCRs.
• The Recql5 mutant mice will be made available to the research community for future studies.