M. V. Shepelev, D. S. Komkov, D. S. Golubev, S. E. Borovikova, D. V. Mazurov, N. A. Kruglova
{"title":"Donor DNA Modification with Cas9 Targeting Sites Improves the Efficiency of MTC34 Knock-in into the CXCR4 Locus","authors":"M. V. Shepelev, D. S. Komkov, D. S. Golubev, S. E. Borovikova, D. V. Mazurov, N. A. Kruglova","doi":"10.1134/s0026893324700250","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>To successfully apply the genome editing technology using the CRISPR/Cas9 system in the clinic, it is necessary to achieve a high efficiency of knock-in, which is insertion of a genetic construct into a given locus of the target cell genome. One of the approaches to increase the efficiency of knock-in is to modify donor DNA with the same Cas9 targeting sites (CTS) that are used to induce double-strand breaks (DSBs) in the cell genome (the double-cut donor method). Another approach is based on introducing truncated CTS (tCTS), including a PAM site and 16 proximal nucleotides, into the donor DNA. Presumably, tCTS sites do not induce cleavage of the donor plasmid, but can support its transport into the nucleus by Cas9. However, the exact mechanisms whereby these two donor DNA modifications increase the knock-in level are unknown. In this study, the modifications were tested for effect on the knock-in efficiency of the <i>MTC34</i> genetic construct encoding the HIV-1 fusion inhibitory peptide MT-C34 into the <i>CXCR4</i> locus of the CEM/R5 T-cell line. When full-length CTSs were introduced into the donor plasmid DNA, the knock-in level was doubled regardless of the CTS number or position relative to the donor sequence. Modifications with tCTSs did not affect the knock-in levels. In vitro, both CTS and tCTS were efficiently cleaved by Cas9. To understand the mechanism of action of these modifications in detail, it is necessary to evaluate their cleavage both in vitro and in vivo.</p>","PeriodicalId":18734,"journal":{"name":"Molecular Biology","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular Biology","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1134/s0026893324700250","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
To successfully apply the genome editing technology using the CRISPR/Cas9 system in the clinic, it is necessary to achieve a high efficiency of knock-in, which is insertion of a genetic construct into a given locus of the target cell genome. One of the approaches to increase the efficiency of knock-in is to modify donor DNA with the same Cas9 targeting sites (CTS) that are used to induce double-strand breaks (DSBs) in the cell genome (the double-cut donor method). Another approach is based on introducing truncated CTS (tCTS), including a PAM site and 16 proximal nucleotides, into the donor DNA. Presumably, tCTS sites do not induce cleavage of the donor plasmid, but can support its transport into the nucleus by Cas9. However, the exact mechanisms whereby these two donor DNA modifications increase the knock-in level are unknown. In this study, the modifications were tested for effect on the knock-in efficiency of the MTC34 genetic construct encoding the HIV-1 fusion inhibitory peptide MT-C34 into the CXCR4 locus of the CEM/R5 T-cell line. When full-length CTSs were introduced into the donor plasmid DNA, the knock-in level was doubled regardless of the CTS number or position relative to the donor sequence. Modifications with tCTSs did not affect the knock-in levels. In vitro, both CTS and tCTS were efficiently cleaved by Cas9. To understand the mechanism of action of these modifications in detail, it is necessary to evaluate their cleavage both in vitro and in vivo.
期刊介绍:
Molecular Biology is an international peer reviewed journal that covers a wide scope of problems in molecular, cell and computational biology including genomics, proteomics, bioinformatics, molecular virology and immunology, molecular development biology, molecular evolution and related areals. Molecular Biology publishes reviews, experimental and theoretical works. Every year, the journal publishes special issues devoted to most rapidly developing branches of physical-chemical biology and to the most outstanding scientists.