2023-12-04 デューク大学(Duke)
◆CRISPR-Casはバクテリアの免疫システムで、ウイルスのDNAを標的に破壊します。新手法は、ゲノム編集に必要なCasタンパク質とRNA分子を利用し、標的DNAに結合する際に必要なPAM配列に対する制約を緩和するものです。
<関連情報>
- https://pratt.duke.edu/news/expanding-crisprs-access-to-the-genome/
- https://www.nature.com/articles/s41467-023-41829-y
人工キメラCas9によるPAMフレキシブルゲノム編集 PAM-flexible genome editing with an engineered chimeric Cas9
Lin Zhao,Sabrina R. T. Koseki,Rachel A. Silverstein,Nadia Amrani,Christina Peng,Christian Kramme,Natasha Savic,Martin Pacesa,Tomás C. Rodríguez,Teodora Stan,Emma Tysinger,Lauren Hong,Vivian Yudistyra,Manvitha R. Ponnapati,Joseph M. Jacobson,George M. Church,Noah Jakimo,Ray Truant,Martin Jinek,Benjamin P. Kleinstiver,Erik J. Sontheimer & Pranam Chatterjee
Nature Communications Published:04 October 2023
DOI:https://doi.org/10.1038/s41467-023-41829-y
Abstract
CRISPR enzymes require a defined protospacer adjacent motif (PAM) flanking a guide RNA-programmed target site, limiting their sequence accessibility for robust genome editing applications. In this study, we recombine the PAM-interacting domain of SpRY, a broad-targeting Cas9 possessing an NRN > NYN (R = A or G, Y = C or T) PAM preference, with the N-terminus of Sc + +, a Cas9 with simultaneously broad, efficient, and accurate NNG editing capabilities, to generate a chimeric enzyme with highly flexible PAM preference: SpRYc. We demonstrate that SpRYc leverages properties of both enzymes to specifically edit diverse PAMs and disease-related loci for potential therapeutic applications. In total, the approaches to generate SpRYc, coupled with its robust flexibility, highlight the power of integrative protein design for Cas9 engineering and motivate downstream editing applications that require precise genomic positioning.
