On October 23rd, Professor Fei Teng's research team in the Biotechnology Research Institute of College of Life Sciences and Health at NEU published a research paper titled "Intrinsictargeting of host RNA by Cas13 constrains its utility" online in the internationally authoritative academic journal "Nature Biomedical Engineering" (impact factor 28.1). NEU is the first author unit of this paper, with doctor Li Zexu and Li Zihan from the College of Life Sciences and Health at NEU and post-doctor Cheng Xiaolong from the Children's National Medical Center as co-first authors. Professor Fei Teng and Professor Li Wei from the Children's National Medical Center in Washington, D.C. are co-corresponding authors.
In recent years, various CRISPR gene editing technologies have developed rapidly. In terms of RNA gene editing tools, the CRISPR-Cas13 system was developed earliest and is currently the most widely applied . As a powerful RNA manipulation tool, the Cas13 toolkit can achieve specific knockdown, editing, imaging, and nucleic acid detection of RNA, and has great potential for application in the field of gene therapy.
This study by Prof. Fetten's team reveals that Cas13 has a novel non-crRNA-dependent endogenous RNA-targeting activity, the presence of which can result in individual forms of Cas13 effector proteins being unable to be delivered properly to target cells via lentiviral vectors, thus affecting the normal application of Cas13 tools. To address these issues, the research team proposed a set of practical principles for the use of Cas13 tools delivered by lentiviral vectors. These findings further suggest that one needs to be alert to the potentially uncertain effects of this endogenous RNA targeting activity when using the Cas13 system.
At the same time, the journal Nature Biomedical Engineering issued a research brief titled "Intrinsic RNA targeting constraints of CRISPR-Cas13 systems" to promote the results of this study. The editorial team of the magazine commented, "In the absence of CRISPR RNA involvement, Cas13 can inherently cleave endogenous RNA in mammalian cells, indicating that there may be more unrecognized mechanisms for CRISPR nucleases. In addition, Cas13's endogenous RNA targeting activity may affect its application in precise targeting scenarios.
In addition, this study is another important achievement in the field of Cas13RNA gene editing tools achieved by the collaborative research team of Professor Fei Teng and Professor Li Wei, following their publication in Nature Communications in the first half of 2023 revealing the principles of crRNA design for the CRISPR-Cas13d system.
Figure: Evaluation of Cas13 system using high-throughput CRISPR-Cas13 screening technology
