Cell: The next generation of gene editing technology CRISPRoff opens the surface...

Text | Li Yuan

Genome editing tools represented by the CRISPR/Cas9 system need to change the DNA sequence when functioning, and often face safety issues caused by off-target.

More and more studies have proved that the epigenome plays a central role in viral infections and cancer.

On April 9, in a paper published in Cell, researchers from the University of California, San Francisco and Massachusetts Institute of Technology developed a new type of epigenetic genome editing tool "CRISPRoff".

Source: Cell

The CRISPR system can become an effective gene editing tool due to two important functional components: one is DNA endonuclease that performs DNA cutting function.

In order to construct CRISPRoff that acts on the epigenome, the researchers retained the homing device of CRISPR, removed the function of the DNA-cutting enzyme, and then added an enzyme that acts on the epigenome.

Source: Cell

Researchers used this tool to target the silencing of endogenous CLTA genes, observe the persistence of epigenetic memory, and detect the expression of CLTA in single-cell clones.

Source: Cell

In addition to its excellent durability characteristics, CRISPRoff is also reversible.

CRISPRon reverses gene silencing (Source: Cell)

The traditional view is that methylation can only silence cytosine in CpG islands (CGI), and nearly one-third of human genes lack CpG islands, so researchers suspect that about 30% of human genes do not respond to new tools.

CRISPRoff silences genes without CpG island structure (Source: Cell)

Finally, the researchers explored the therapeutic potential of CRISPRoff in induced pluripotent stem cells.

CRISPRoff gene silencing in iPSC and iPSC differentiated neurons (Source: Cell)

This shows that CRISPRoff can achieve long-lasting treatment with only one administration, which reflects the huge therapeutic potential of CRISPRoff.

In general, this programmable epigenome editing is adjustable and reversible without cutting DNA, thereby effectively avoiding the cytotoxicity associated with gene editing.

Reference materials:

[1] James Nuñez et al.