The Double Nickase Plasmid features a U6 promoter for sgRNA expression, a 20 nt targeting sequence, and a gRNA scaffold to guide Cas9n. It includes a CBh promoter for Cas9n (D10A) and puromycin resistance, GFP for transfection verification, and nuclear localization signals (NLS). The 2A peptide allows co-expression of Cas9n and Puro from a single promoter, enabling precise genome editing with reduced off-target effects.
The Double Nickase Plasmid features a U6 promoter for sgRNA expression, a 20 nt targeting sequence, and a gRNA scaffold to guide Cas9n. It includes a CBh promoter for Cas9n (D10A) and puromycin resistance, GFP for transfection verification, and nuclear localization signals (NLS). The 2A peptide allows co-expression of Cas9n and Puro from a single promoter, enabling precise genome editing with reduced off-target effects.
Cas9n Nickase gRNA Plasmid Targeting: Dual gRNA plasmids create single-strand nicks at precise DNA sequences for efficient genome editing using Cas9n Nickase.
This image illustrates the Cas9n Nickase mechanism used for precise genome editing. Two plasmids (Plasmid 1 and Plasmid 2) are shown, each containing a targeted DNA sequence. The system utilizes single-guide RNAs (sgRNA) to direct Cas9n Nickase to specific genomic locations, represented by the blue and pink DNA strands. The sgRNA scaffold aids in guiding Cas9n to the 20 nucleotide (nt) target sequence on the DNA. Cas9n makes single-strand cuts at NCC and NGG sites, enabling precise gene modifications without creating double-strand breaks.
The Double Nickase Plasmid features a U6 promoter for sgRNA expression, a 20 nt targeting sequence, and a gRNA scaffold to guide Cas9n. It includes a CBh promoter for Cas9n (D10A) and puromycin resistance, GFP for transfection verification, and nuclear localization signals (NLS). The 2A peptide allows co-expression of Cas9n and Puro from a single promoter, enabling precise genome editing with reduced off-target effects.
小鼠 Gzmb 基因编码颗粒酶 B(granzyme B),这是一种细胞毒性丝氨酸蛋白酶,储存在活化的 CD8+ T 细胞和 NK 细胞的溶解颗粒中,并在免疫突触处释放以清除靶细胞。颗粒酶 B 在穿孔素介导进入细胞质后,会切割关键底物以启动凋亡与炎症程序,包括激活半胱天冬酶(caspase),以及裂解可放大细胞死亡信号的细胞内蛋白。Gzmb 的活性是细胞毒性淋巴细胞效应功能的核心,并塑造抗原特异性免疫,对免疫监视、免疫病理以及炎症环境中的组织损伤均具有广泛意义。在小鼠模型中,颗粒酶 B 的表达或活性失调与免疫细胞细胞毒性改变有关,并可影响类自身免疫性炎症、感染应答以及肿瘤–免疫相互作用的严重程度。
granzyme B 双切酶质粒(m)由一对匹配的质粒组成,专为在 mouse 细胞系中对 Gzmb 位点进行高特异性编辑而设计。每个质粒分别表达Cas9 D10A切口酶和针对Gzmb内不同DNA链的独特sgRNA。当这两种切口酶被引导至相邻但位于DNA链相反侧的位点时,会产生错位的单链切口,从而共同形成错位双链断裂,这需要两个引导RNA在靶位点上协同发挥作用。由此产生的DNA断裂通过内源性细胞修复途径(最常见的是非同源末端连接(NHEJ))得到修复,从而导致插入或缺失,进而破坏Gzmb的功能。通过要求双sgRNA在靶位点结合,双切口方法提高了编辑特异性,并为需要对靶向精度进行额外控制的应用提供了互补的CRISPR策略。