Aug 2026· Trends in Biotechnology· 0 citations· 40 references
Medicine
TL;DR
An RNA-guided bridge recombinase system is engineered through rational mutagenesis and AI-assisted directed evolution, enabling programmable chromosomal rearrangements in both plant and mammalian cells and achieving up to a 29.8-fold increase in activity.
Abstract
Precise manipulation of large DNA fragments in eukaryotic genomes remains limited by the low efficiency and delivery constraints of current multicomponent editing systems. In this study, we engineered an RNA-guided bridge recombinase system through rational mutagenesis and AI-assisted directed evolution, enabling programmable chromosomal rearrangements in both plant and mammalian cells and achieving up to a 29.8-fold increase in activity. In plants, the optimized system mediated precise deletions, insertions, and inversions from 1.8- to 315-kb DNA fragments, with stable editing efficiencies of up to 23.9% in regenerated rice plants. We further generated herbicide-resistant rice through a 315-kb chromosomal inversion that rewired endogenous promoter activity. In mammalian cells, the compact ISCro4 recombinase system was delivered using a single adeno-associated virus vector, thereby supporting efficient genome editing. Together, these results establish bridge RNA-guided recombinases as a versatile platform for programmable chromosome-scale genome engineering, with broad potential for precision breeding and gene therapy.
The reconstituted and engineered Type I-F CAST is established as a functional platform for programmable DNA insertion in plants and provides a foundation for developing targeted genome-engineering technologies for crop biotechnology.
Yunqing Wang, Kimberley T Muchenje, Ashot Papikian et al.· bioRxiv· 0 citations
Genomic manipulation has advanced from stochastic nuclease‐mediated disruption toward programmable, deterministic precision. Early clustered regularly interspaced short palindromic repeats (CRISPR) strategies enabled targeted mutagenesis through double‐strand breaks; however, their therapeutic application is limited by genotoxicity, chromosomal instability, and dependence on endogenous repair pathways that are difficult to predict. In this review, we examined the transition from gene editing to genome writing, an approach that decouples genomic modification from host repair pathways to better balance efficiency, precision, and payload delivery. We also discussed the principles of precision technologies, including base and prime editors, and described emerging large‐scale writers, such as CRISPR‐associated transposases and recombinase‐based bridge RNAs, which enable the integration of multi‐kilobase synthetic modules. Beyond enzymatic mechanisms, we further considered the combined use of generative artificial intelligence, structural biology, and novel delivery architectures as potential strategies to overcome current biological limitations. Taken together, these developments point toward Generative Biology, in which computational design and high‐throughput screening transform the genome from a static substrate into a more dynamic model for complex, synthetic functional design.
This Protocol leverages prime editing to insert recombinase recognition sites into repetitive genomic regions, such as LINE-1 elements, thereby enabling extensive genetic modifications in human cells, and supports a wide range of studies, including genome-wide functional analyses and essentiality mapping.
Lisa M. Riedmayr, Jonas Koeppel, George M. Church et al.· Nature Protocols· 0 citations
A programmable gene replacement tool, named prime assembly (PA), which adapts prime editors to produce one or two pairs of 3'-flaps on both the genome and donor DNA, allowing megabase-scale genomic excision and/or kilobase-scale donor insertion at the gene of interest.
Hojun Jung, Bada Jeong, Yong-Woo Kim et al.· Nature Biotechnology· 0 citations
An improved tool called pSPIN-GG and supporting protocols for simplified CAST-based genome engineering are presented and refinements support accelerated library construction, reduce assembly and screening burden, and expand the accessibility of CAST systems for multiplexed bacterial genome engineering.
Thea C T Irvine, Andrew M Bailey, Thomas E. Gorochowski· Methods in molecular biology· 0 citations