CRISPR-Cas9 genome engineering is a powerful technology for correcting genetic diseases. However, the targeting range of Cas9 proteins is limited by their requirement for a protospacer adjacent motif (PAM), and in vivo delivery is challenging due to their large size. Here, we use phage-assisted continuous directed evolution to broaden the PAM compatibility of Campylobacter jejuni Cas9 (CjCas9), the smallest Cas9 ortholog characterized to date. The identified variant, termed evoCjCas9, primarily recognizes NAH and NHA PAM sequences, which occur tenfold more frequently in the genome than the canonical NVRYAC PAM site. Moreover, evoCjCas9 exhibits higher nuclease activity than wild-type CjCas9 on canonical PAMs, with editing rates comparable to commonly used PAM-relaxed SpCas9 variants. Combined with deaminases or reverse transcriptases, evoCjCas9 enables robust base and prime editing, with the small size of evoCjCas9 base editors allowing for tissue-specific installation of A-to-G or C-to-T transition mutations from single adeno-associated virus vector systems.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7616171PMC
http://dx.doi.org/10.1038/s41589-023-01427-xDOI Listing

Publication Analysis

Top Keywords

continuous directed
8
directed evolution
8
pam compatibility
8
pam
5
evolution compact
4
compact cjcas9
4
cjcas9 variant
4
variant broad
4
broad pam
4
compatibility crispr-cas9
4

Similar Publications

Breaking a barrier: In trans vlsE recombination and genetic manipulation of the native vlsE gene of the Lyme disease pathogen.

PLoS Pathog

January 2025

Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America.

Host-pathogen interactions represent a dynamic evolutionary process, wherein both hosts and pathogens continuously develop complex mechanisms to outmaneuver each other. Borrelia burgdorferi, the Lyme disease pathogen, has evolved an intricate antigenic variation mechanism to evade the host immune response, enabling its dissemination, persistence, and pathogenicity. Despite the discovery of this mechanism over two decades ago, the precise processes, genetic elements, and proteins involved in this system remain largely unknown.

View Article and Find Full Text PDF

High Mobility Emissive Organic Semiconductors for Optoelectronic Devices.

J Am Chem Soc

January 2025

Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.

High mobility emissive organic semiconductors (HMEOSCs) are a kind of unique semiconducting material that simultaneously integrates high charge carrier mobility and strong emission features, which are not only crucial for overcoming the performance bottlenecks of current organic optoelectronic devices but also important for constructing high-density integrated devices/circuits for potential smart display technologies and electrically pumped organic lasers. However, the development of HMEOSCs is facing great challenges due to the mutually exclusive requirements of molecular structures and packing modes between high charge carrier mobility and strong solid-state emission. Encouragingly, considerable advances on HMEOSCs have been made with continuous efforts, and the successful integration of these two properties within individual organic semiconductors currently presents a promising research direction in organic electronics.

View Article and Find Full Text PDF

Background: Dementia leads to cognitive decline affecting memory, thinking, and behavior. Current pharmaceutical treatments are symptomatic, with limited efficacy and significant drawbacks. Ginkgo biloba extract (EGb761) is being explored as an adjuvant therapy for dementia because of its potential neuroprotective effects.

View Article and Find Full Text PDF

An Atomistic Analysis of the Carpet Growth of KCl Across Step Edges on the Ag(111) Surface.

J Phys Chem Lett

January 2025

Clausius Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn 53115, Germany.

The carpet growth of alkali halide (AH) layers across step edges of substrates enables the growth of seamless and continuous large domains. Yet, information about how the AH layer adapts continuously to the height difference between the terraces on the two sides of a step is only described by continuum models, which do not give details of the ionic displacements. Here, we present a first study of thin epitaxial KCl(100) layers grown on the Ag(111) surface by scanning tunneling microscopy that provides atomistic details for the first time.

View Article and Find Full Text PDF

The Impact of Artificial Intelligence and Machine Learning in Organ Retrieval and Transplantation: A Comprehensive Review.

Curr Res Transl Med

January 2025

Department of Research and Innovation, Medway NHS Foundation Trust, Gillingham ME7 5NY, United Kingdom; Faculty of Medicine, Health and Social Care, Canterbury Christ Church University, United Kingdom.

This narrative review examines the transformative role of Artificial Intelligence (AI) and Machine Learning (ML) in organ retrieval and transplantation. AI and ML technologies enhance donor-recipient matching by integrating and analyzing complex datasets encompassing clinical, genetic, and demographic information, leading to more precise organ allocation and improved transplant success rates. In surgical planning, AI-driven image analysis automates organ segmentation, identifies critical anatomical features, and predicts surgical outcomes, aiding pre-operative planning and reducing intraoperative risks.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!