AccuTool™ gRNA & Donor Design Service provides designs of gRNA and Donor template optimized for an efficient CRISPR-Cas9 genome editing.
Designing accurate gRNA is the key to successful genome editing using the CRISPR-Cas9 system.
gRNA is a single-stranded RNA composed of tracrRNA, which forms a complex with Cas9 nuclease, and a 20-nt crRNA that binds to the target DNA region with complementary base pairing (Figure 1).
Simply altering the target sequence of gRNA can change the active region of Cas9 nuclease.
Therefore, designing and synthesizing gRNA is the most fundamental step in CRISPR-Cas9 experiments.
Figure 1. gRNA and Cas9 nuclease
A stem-loop structure of tracrRNA and the target-specific crRNA form a complex with Cas9 nuclease to perform a genome editing.
Homology-directed repair (HDR) is a major DSBs repair system, capable of performing gene knock-in/out, replacement, and point mutations.
The Knock-in, which inserts a target gene into a specific part of the genome, restores DSBs by inserting a donor template containing a homologous sequence, so precise genome editing is possible through the HDR system.