CRISPR/Cas9 taught to edit DNA without breaking

Denis Strigun, Naked Science

A group of researchers with the participation of specialists from Kobe University has developed a genome editing technology based on CRISPR/Cas9 technology, which does not involve DNA splitting. The results of the work are presented in the journal Science (Nishida et al., Targeted nucleotide editing using hybrid prokaryotic and vertical adaptive immune systems).

CRISPR/Cas9 is a genome editing technology proposed in 2012. It is based on the ability of Cas9 nucleases to recognize a virus entering a bacterial cell and, if there are fragments of it in the bacterial DNA, to tear the viral genome, protecting the cell from infection. Then the incision site is restored naturally or artificially. Despite widespread adoption in recent years, CRISPR/Cas9 has drawbacks. Thus, it does not allow for precise induced genome mutations, and DNA cleavage is cytotoxic.

In a new study, scientists have developed a more targeted Target-AID technology. The authors replaced the Cas9 endonuclease with an artificial nuclease and, using a linker, added an activation-induced cytidine deaminase (AID), an RNA–editing enzyme, to the CRISPR/Cas9 system. In the course of work, guide RNA recognizes the desired sequence of nucleotides and AID changes it, while DNA cleavage does not occur. The technology worked on yeast fungi and mammals and was characterized by significantly lower cytotoxicity.

Drawing from the Kobe University press release
Researchers succeed in developing a genome editing technique that does not cleave DNA – VM

According to the researchers, unlike other genome editing technologies, Target-AID provides a greater variety and a high level of operations. In addition, it relieves bacterial cells from unnecessary stress. It is expected that the new technology will be used as an independent or additional tool in genetic engineering. In particular, it may replace CRISPR/Cas9 in the treatment of hereditary diseases, mental disorders, as well as pharmaceutical developments.

Portal "Eternal youth" http://vechnayamolodost.ru  31.08.2016