New genome editing tool CRISPR/Cas12b: Able to edit human cell genomes.

In recent years, CRISPR gene editing technology and its related applications have become a hot research direction in the field of life science.
based on this technology, scientists can efficiently, quickly and easily edit genes of interest, thus making them important applications in the development of basic research, agriculture and medicine.
two types of active protein families (Cas9 and Cas12a/Cpf1) in the crispR system have been successfully transformed into genome editing tools for mammals and other model organisms, including the Cas9 system, first reported in 2012 and 2013 by laboratories such as Doudna JA, Charpentier E and Zhang F.
she/she used cas9 system to effectively edit the mammalian genome, and led to the rapid development of gene editing, and successfully expanded gene editing technology into a variety of biological applications such as gene transcription expression regulation, epigenetic modification, whole genome functional screening, base editing, genomic imaging and cell lineage tracking. The Cas12a (also known as Cpf1) system, discovered and modified by
and Zhang F in 2015, also enables genome editing of several species, including mammals.
at the same time, scientists are working on new gene-editing systems, especially tool systems that are more suitable for gene therapy.
a new CRISPR system, Cas12b (also known as C2c1), identified in recent years, because of its high temperature-obsessed properties, which were not used in genome editing.
the research team of the Institute of Zoology of the Chinese Academy of Sciences successfully identified a number of Cas12b/C2c1 enzymes that can work at the physiological temperature of the human body through systematic excavation.
system modified, two Cas12b/C2c1 enzymes have been successfully developed into mammalian genome editing tools that can edit human cell genomes and be used to prepare animal disease models.
these Cas12b/C2c1 sasses are dual RNA-guided nucleases that identify the PAM sequence of 5'-TTN, cutting DNA and producing sticky ends.
further modifications can be used in extended applications such as genome activation using these Cas12b/C2c1 enzymes.
Cas12b/C2c1 enzyme has several advantages and characteristics compared to the previously reported Cas9 and Cas12a/Cpf1 enzymes: (1) Cas12b/C2c1 is smaller than the most widely used SpCas9 and Cas12a/Cpf1, making it easier to use gene therapy that requires body delivery.
(2) Cas12b/C2c1 maintains high enzyme activity over a wide temperature range and pH range, and is expected to be suitable for multiple species with different physiological temperatures.
also had a more stable Cas12b/C2c1 rnayconucleus (RNP) in human plasma than SpCas9.
(3) Cas12b/C2c1 is difficult to tolerate the base mismatch between the wizard RNA and the target DNA, so it has a smaller off-target effect than SpCas9 and Cas12a/Cpf1, which means it is safer for genome editing.
the new technology, which the research team filed a patent application a year ago and is developing its application in gene therapy.
results were published on November 27 in the international academic journal Cell Discovery.
the research was carried out by the Institute of Animal studies and the Institute of Stem Cell and Regenerative Medicine Innovation of the Chinese Academy of Sciences. Li Wei, a researcher at the
Animal Institute, is the communication author of the paper, and Dr. Teng Fei and Cui Wei are co-first authors.
the research by the Chinese Academy of Sciences strategic science and technology pilot special and the Ministry of Science and Technology, fund committee and other funding.
Source: Animal Research Institute.