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Targeting DNA Repair Pathways with B02 and Nocodazole Small Molecules to Improve CRIS-PITCh Mediated Cassette Integration in CHO-K1 Cells

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Journal Sci Rep
Specialty Science
Date 2023 Feb 22
PMID 36813818
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Abstract

CRISPR-mediated integration could be used to develop the recombinant CHO (rCHO) cells by knock-in into the hotspot loci. However, low HDR efficiency besides the complex donor design is the main barrier for achieving so. The recently introduced MMEJ-mediated CRISPR system (CRIS-PITCh) uses a donor with short homology arms, being linearized in the cells via two sgRNAs. In this paper, a new approach to improve CRIS-PITCh knock-in efficiency by employing small molecules was investigated. Two small molecules, B02, a Rad51 inhibitor, and Nocodazole, a G2/M cell cycle synchronizer, were used to target the S100A hotspot site using a bxb1 recombinase comprised landing pad in CHO-K1 cells. Following transfection, the CHO-K1 cells were treated with the optimum concentration of one or combination of small molecules, being determined by the cell viability or flow cytometric cell cycle assay. Stable cell lines were generated and the single-cell clones were achieved by the clonal selection procedure. The finding showed that B02 improved the PITCh-mediated integration approximately twofold. In the case of Nocodazole treatment, the improvement was even more significant, up to 2.4-fold. However, the combinatorial effects of both molecules were not substantial. Moreover, according to the copy number and out-out PCR analyses, 5 and 6 of 20 clonal cells exhibited mono-allelic integration in Nocodazole and B02 groups, respectively. The results of the present study as the first attempt to enhance the CHO platform generation by exploiting two small molecules in the CRIS-PITCh system could be used in future researches to establish rCHO clones.

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References
1.
Alagpulinsa D, Ayyadevara S, Shmookler Reis R . A Small-Molecule Inhibitor of RAD51 Reduces Homologous Recombination and Sensitizes Multiple Myeloma Cells to Doxorubicin. Front Oncol. 2014; 4:289. PMC: 4214226. DOI: 10.3389/fonc.2014.00289. View

2.
Aida T, Nakade S, Sakuma T, Izu Y, Oishi A, Mochida K . Gene cassette knock-in in mammalian cells and zygotes by enhanced MMEJ. BMC Genomics. 2016; 17(1):979. PMC: 5126809. DOI: 10.1186/s12864-016-3331-9. View

3.
Bachu R, Bergareche I, Chasin L . CRISPR-Cas targeted plasmid integration into mammalian cells via non-homologous end joining. Biotechnol Bioeng. 2015; 112(10):2154-62. DOI: 10.1002/bit.25629. View

4.
Vu T, Doan D, Kim J, Sung Y, Tran M, Song Y . CRISPR/Cas-based precision genome editing via microhomology-mediated end joining. Plant Biotechnol J. 2020; 19(2):230-239. PMC: 7868975. DOI: 10.1111/pbi.13490. View

5.
Lee J, Kallehauge T, Pedersen L, Kildegaard H . Site-specific integration in CHO cells mediated by CRISPR/Cas9 and homology-directed DNA repair pathway. Sci Rep. 2015; 5:8572. PMC: 4339809. DOI: 10.1038/srep08572. View