Prime Editing (PE)

Genome editing technology can modify plant genomes in a targeted manner, thereby greatly accelerating the process of plant breeding, which is an important technological breakthrough for achieving precise crop breeding. As a new gene editing system, PE can realize any type of base substitution, precise insertion and deletion of small fragments at targeted sites of the genome. This flexible and designable genetic modification capability enables that it has great potential in plant genetic modification.

PE is a method of genome editing based on "search-and-replace". The efficiency of PE is similar to that of the base editor, but the specificity is higher than that of previous systems. PE can introduce indels and all twelve base-to-base conversions (including conversions and transversions) without causing DNA double-strand breaks. The guided editing system consists of two parts. One is an effector protein composed of nCas9 and an engineered reverse transcriptase (RT). The other is prime editing guide RNA (pegRNA) containing a primer binding site sequence (PBS) and an RT template sequence. Under the guidance of pegRNA, the PE effector protein binds to the target site, cuts the non-target strands to produce nicks, and releases free single strands that can bind to its PBS sequence, thereby initiating the reverse transcription process of the RT template, and then repairing it through DNA repair. The corresponding base changes on the RT template are introduced into the genome.

Figure 1. Prime Editing system. (Marzec et al. 2020)

PE has many advantages compared to other genome editing technologies.

• Relatively less restricted by PAM. Prime Editing expands the scope of CRISPR genome editing because it can be edited close to or far from the PAM site. It is reported that the distance from PAM to the editing point can exceed 30 bp.
• Universal and easy. Prime editing can realize different editing purposes including twelve base conversions, small fragment base insertions and deletions, etc.
• Precise and flexible. When there are multiple identical bases near the target site, it will not be troubled by the base editor bystander mutation problem.

Lifeasible has invested a lot of resources in the research and development of gene editing for several years, and has accumulated a wealth of experience for relevant technologies. We are devoted to optimizing the CRISPR system to achieve genetic modification. We can provide Prime Editing service to help customers modify the plant genome in a targeted manner.

PE experiment procedure

We hope that our technology and services can help you achieve new breakthroughs. For more information, please contact Lifeasible.