Adv Sci | 顾臻/肖庆全/魏迎辉/李国玲团队合作开发紧凑型Cas9d碱基编辑器

TL;DR - Researchers used AlphaFold3-guided engineering to create Cas9d Ultra, a compact and highly specific genome-editing system suitable for single-AAV delivery. Its derived base editors achieved in vivo Pcsk9 editing and lowered LDL cholesterol in mice, supporting potential single-vector gene therapies.

• Cas9d Ultra combines a shortened, stabilized gRNA scaffold with protein mutations that strengthen interactions with gRNA and target DNA.
• The engineered system exceeded 60% cutting efficiency in mammalian cells—a 3.1-fold improvement over wild-type Cas9d—and showed high specificity in GUIDE-seq testing.
• Cas9d-derived adenine and cytosine base editors enabled embryo editing, including Tyr knockout and generation of albino mice.
• Single-AAV delivery produced 3.5%–11.9% liver editing with 9dABE and an average 15.7% with 9dCBE, reaching 28.9% and significantly reducing serum LDL-C.