Compact and versatile CRISPR-Cas systems will enable genome engineering applications through high-efficiency delivery in a wide variety of contexts. Here, we create an efficient miniature Cas system (CasMINI) engineered from the type V-F Cas12f (Cas14) system by guide RNA and protein engineering, which is less than half the size of currently used CRISPR systems (Cas9 or Cas12a). We demonstrate that CasMINI can drive high levels of gene activation (up to thousands-fold increases), while the natural Cas12f system fails to function in mammalian cells. We show that the CasMINI system has comparable activities to Cas12a for gene activation, is highly specific, and allows robust base editing and gene editing. We expect that CasMINI can be broadly useful for cell engineering and gene therapy applications ex vivo and in vivo.

紧凑且多功能的 CRISPR-Cas 系统将通过在各种环境下高效传递来实现基因组工程应用。在这里，我们通过向导RNA和蛋白质工程从VF型Cas12f（Cas14）系统中创建了一个高效的微型Cas系统（CasMINI），其大小不到目前使用的CRISPR系统（Cas9或Cas12a）的一半。我们证明 CasMINI 可以驱动高水平的基因激活（高达数千倍），而天然的 Cas12f 系统无法在哺乳动物细胞中发挥作用。我们证明 CasMINI 系统在基因激活方面具有与 Cas12a 相当的活性，具有高度特异性，并且允许强大的碱基编辑和基因编辑。我们期望 CasMINI 可广泛用于离体和体内的细胞工程和基因治疗应用。