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Ohno T, Nakane T, Akase T, Kurasawa H, Aizawa Y. Development of an isogenic human cell trio that models polyglutamine disease. Genes Genet Syst 2023; 98:179-189. [PMID: 37821389 DOI: 10.1266/ggs.22-00030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Abstract
Polyglutamine (polyQ) diseases are rare autosomal-dominant neurodegenerative diseases associated with the expansion of glutamine-encoding triplet repeats in certain genes. To investigate the functional influence of repeat expansion on disease mechanisms, we applied a biallelic genome-engineering platform that we recently established, called Universal Knock-in System or UKiS, to develop a human cell trio, a set of three isogenic cell lines that are homozygous for two different numbers of repeats (first and second lines) or heterozygous for the two repeat numbers (third line). As an example of a polyQ disease, we chose spinocerebellar ataxia type 2 (SCA2). In a pseudodiploid human cell line, both alleles of the glutamine-encoding triplet repeat in the SCA2-causing gene, ataxin 2 or ATXN2, were first knocked in with a donor sequence encoding both thymidine kinase and either puromycin or blasticidin resistance proteins under dual drug selection. The knocked-in donor alleles were then substituted with a payload having either 22 or 76 triplet repeats in ATXN2 by ganciclovir negative selection. The two-step substitution and subsequent SNP typing and genomic sequencing confirmed that the SCA2-modeling isogenic cell trio was obtained: three clones of 22-repeat homozygotes, two clones of 22/76-repeat heterozygotes and two clones of 76-repeat homozygotes. Finally, RT-PCR and immunoblotting using the obtained clones showed that, consistent with previous observations, glutamine tract expansion reduced transcriptional and translational expression of ATXN2. The cell clones with homozygous long-repeat alleles, which are rarely obtained from patients with SCA2, showed more drastic reduction of ATXN2 expression than the heterozygous clones. This study thus demonstrates the potential of UKiS, which is a beneficial platform for the efficient development of cell models not only for polyQ diseases but also for any other genetic diseases, which may accelerate our deeper understanding of disease mechanisms and cell-based screening for therapeutic drugs.
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Affiliation(s)
- Tomoyuki Ohno
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Takeshi Nakane
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Taichi Akase
- School of Life Science and Technology, Tokyo Institute of Technology
| | - Hikaru Kurasawa
- School of Life Science and Technology, Tokyo Institute of Technology
- Kanagawa Institute of Industrial Science and Technology
| | - Yasunori Aizawa
- School of Life Science and Technology, Tokyo Institute of Technology
- Kanagawa Institute of Industrial Science and Technology
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2
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Biallelic and gene-wide genomic substitution for endogenous intron and retroelement mutagenesis in human cells. Nat Commun 2022; 13:4219. [PMID: 35864085 PMCID: PMC9304424 DOI: 10.1038/s41467-022-31982-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 07/13/2022] [Indexed: 01/09/2023] Open
Abstract
Functional annotation of the vast noncoding landscape of the diploid human genome still remains a major challenge of genomic research. An efficient, scarless, biallelic, and gene-wide mutagenesis approach is needed for direct investigation of the functional significance of endogenous long introns in gene regulation. Here we establish a genome substitution platform, the Universal Knock-in System or UKiS, that meets these requirements. For proof of concept, we first used UKiS on the longest intron of TP53 in the pseudo-diploid cell line HCT116. Complete deletion of the intron, its substitution with mouse and zebrafish syntenic introns, and specific removal of retrotransposon-derived elements (retroelements) were all efficiently and accurately achieved in both alleles, revealing a suppressive role of intronic Alu elements in TP53 expression. We also used UKiS for TP53 intron deletion in human induced pluripotent stem cells without losing their stemness. Furthermore, UKiS enabled biallelic removal of all introns from three human gene loci of ~100 kb and longer to demonstrate that intron requirements for transcriptional activities vary among genes. UKiS is a standard platform with which to pursue the design of noncoding regions for genome writing in human cells.
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3
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BEAR reveals that increased fidelity variants can successfully reduce the mismatch tolerance of adenine but not cytosine base editors. Nat Commun 2021; 12:6353. [PMID: 34732717 PMCID: PMC8566456 DOI: 10.1038/s41467-021-26461-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 09/27/2021] [Indexed: 12/26/2022] Open
Abstract
Adenine and cytosine base editors (ABE, CBE) allow for precision genome engineering. Here, Base Editor Activity Reporter (BEAR), a plasmid-based fluorescent tool is introduced, which can be applied to report on ABE and CBE editing in a virtually unrestricted sequence context or to label base edited cells for enrichment. Using BEAR-enrichment, we increase the yield of base editing performed by nuclease inactive base editors to the level of the nickase versions while maintaining significantly lower indel background. Furthermore, by exploiting the semi-high-throughput potential of BEAR, we examine whether increased fidelity SpCas9 variants can be used to decrease SpCas9-dependent off-target effects of ABE and CBE. Comparing them on the same target sets reveals that CBE remains active on sequences, where increased fidelity mutations and/or mismatches decrease the activity of ABE. Our results suggest that the deaminase domain of ABE is less effective to act on rather transiently separated target DNA strands, than that of CBE explaining its lower mismatch tolerance.
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4
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Simon-Vecsei Z, Sőth Á, Lőrincz P, Rubics A, Tálas A, Kulcsár PI, Juhász G. Identification of New Interactions between Endolysosomal Tethering Factors. J Mol Biol 2021; 433:166965. [PMID: 33781757 DOI: 10.1016/j.jmb.2021.166965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 02/28/2021] [Accepted: 03/22/2021] [Indexed: 10/21/2022]
Abstract
Proper functioning of the precisely controlled endolysosomal system is essential for maintaining the homeostasis of the entire cell. Tethering factors play pivotal roles in mediating the fusion of different transport vesicles, such as endosomes or autophagosomes with each other or with lysosomes. In this work, we uncover several new interactions between the endolysosomal tethering factors Rabenosyn-5 (Rbsn) and the HOPS and CORVET complexes. We find that Rbsn binds to the HOPS/CORVET complexes mainly via their shared subunit Vps18 and we mapped this interaction to the 773-854 region of Vps18. Based on genetic rescue experiments, the binding between Rbsn and Vps18 is required for endosomal transport and is dispensable for autophagy. Moreover, Vps18 seems to be important for β1 integrin recycling by binding to Rbsn and its known partner Vps45.
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Affiliation(s)
- Zsófia Simon-Vecsei
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary.
| | - Ármin Sőth
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Péter Lőrincz
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary; Premium Postdoctoral Research Program, Eötvös Loránd Research Network, Budapest, Hungary
| | - András Rubics
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - András Tálas
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Péter István Kulcsár
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Gábor Juhász
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary; Institute of Genetics, Biological Research Centre, Szeged, Hungary.
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5
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Ijaz F, Ikegami K. Knock-in of Labeled Proteins into 5'UTR Enables Highly Efficient Generation of Stable Cell Lines. Cell Struct Funct 2021; 46:21-35. [PMID: 33504736 PMCID: PMC10511053 DOI: 10.1247/csf.21002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/14/2021] [Indexed: 11/11/2022] Open
Abstract
Stable cell lines and animal models expressing tagged proteins are important tools for studying behaviors of cells and molecules. Several molecular biology technologies have been applied with varying degrees of success and efficiencies to establish cell lines expressing tagged proteins. Here we applied CRISPR/Cas9 for the knock-in of tagged proteins into the 5'UTR of the endogenous gene loci. With this 5'UTR-targeting knock-in strategy, stable cell lines expressing Arl13b-Venus, Reep6-HA, and EGFP-alpha-tubulin were established with high efficiencies ranging from 50 to 80% in antibiotic selected cells. The localization of the knock-in proteins were identical to that of the endogenous proteins in wild-type cells and showed homogenous expression. Moreover, the expression of knock-in EGFP-alpha-tubulin from the endogenous promoter was stable over long-term culture. We further demonstrated that the fluorescent signals were enough for a long time time-lapse imaging. The fluorescent signals were distinctly visible during the whole duration of the time-lapse imaging and showed specific subcellular localizations. Altogether, our strategy demonstrates that 5'UTR is an amenable site to generate cell lines for the stable expression of tagged proteins from endogenous loci in mammalian cells.Key words: CRISPR/Cas9, knock-in, primary cilium, UTR, tubulin.
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Affiliation(s)
- Faryal Ijaz
- Department of Anatomy and Developmental Biology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Koji Ikegami
- Department of Anatomy and Developmental Biology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
- JST, PRESTO, Kawaguchi, Japan
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6
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Bloemberg D, Sosa-Miranda CD, Nguyen T, Weeratna RD, McComb S. Self-Cutting and Integrating CRISPR Plasmids Enable Targeted Genomic Integration of Genetic Payloads for Rapid Cell Engineering. CRISPR J 2021; 4:104-119. [PMID: 33616439 DOI: 10.1089/crispr.2020.0090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Since observations that CRISPR nucleases function in mammalian cells, many strategies have been devised to adapt them for genetic engineering. Here, we investigated self-cutting and integrating CRISPR-Cas9 plasmids (SCIPs) as easy-to-use gene editing tools that insert themselves at CRISPR-guided locations. SCIPs demonstrated similar expression kinetics and gene disruption efficiency in mouse (EL4) and human (Jurkat) cells, with stable integration in 3-6% of transfected cells. Clonal sequencing analysis indicated that integrants showed bi- or mono-allelic integration of entire CRISPR plasmids in predictable orientations and with limited insertion or deletion formation. Interestingly, including longer homology arms (HAs; 500 bp) in varying orientations only modestly increased knock-in efficiency (by around twofold). Using a SCIP-payload design (SCIPpay) that liberates a promoter-less sequence flanked by HAs thereby requiring perfect homology-directed repair for transgene expression, longer HAs resulted in higher integration efficiency and precision of the payload but did not affect integration of the remaining plasmid sequence. As proofs of concept, we used SCIPpay to insert (1) a gene fragment encoding tdTomato into the CD69 locus of Jurkat cells, thereby creating a cell line that reports T-cell activation, and (2) a chimeric antigen receptor gene into the TRAC locus. Here, we demonstrate that SCIPs function as simple, efficient, and programmable tools useful for generating gene knock-out/knock-in cell lines, and we suggest future utility in knock-in site screening/optimization, unbiased off-target site identification, and multiplexed, iterative, and/or library-scale automated genome engineering.
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Affiliation(s)
- Darin Bloemberg
- Human Health Therapeutics Research Center, National Research Council Canada, Ottawa, Canada
| | | | - Tina Nguyen
- Human Health Therapeutics Research Center, National Research Council Canada, Ottawa, Canada
| | - Risini D Weeratna
- Human Health Therapeutics Research Center, National Research Council Canada, Ottawa, Canada
| | - Scott McComb
- Human Health Therapeutics Research Center, National Research Council Canada, Ottawa, Canada.,University of Ottawa Centre for Infection, Immunity and Inflammation, Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Canada
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7
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Reé D, Borsy A, Fóthi Á, Orbán TI, Várady G, Erdei Z, Sarkadi B, Réthelyi J, Varga N, Apáti Á. Establishing a human embryonic stem cell clone with a heterozygous mutation in the DGCR8 gene. Stem Cell Res 2020; 50:102134. [PMID: 33360445 DOI: 10.1016/j.scr.2020.102134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/21/2020] [Accepted: 12/14/2020] [Indexed: 11/26/2022] Open
Abstract
DiGeorge Syndrome (DGS) Critical Region 8 (DGCR8) is a primary candidate gene in they DGS. The DGCR8 microprocessor complex subunit is an essential cofactor in the canonical miRNA biogenesis which is involved in diverse cellular functions such as cell fate decisions, apoptosis and different signaling pathways. However, the role of DGCR8 in these processes or development of DGS is not fully understood. Here we present a heterozygous DGCR8 mutant human embryonic stem cell line (HuES9DGCR8+/-) created by the CRISPR/Cas9 system. The generated HuES9DGCR8+/- cells maintain normal karyotype, morphology, pluripotency and differentiation capacity into all three germ layers.
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Affiliation(s)
- Dóra Reé
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Adrienn Borsy
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Ábel Fóthi
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Tamás I Orbán
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - György Várady
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Zsuzsa Erdei
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Balázs Sarkadi
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - János Réthelyi
- Department of Psychiatry and Psychotherapy, Semmelweis University, Budapest, Hungary; Molecular Psychiatry Research Group, National Brain Research Program (NAP), Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Nóra Varga
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Ágota Apáti
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary.
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8
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Lu X, Guo Y, Gu S, Tan D, Cheng B, Li Z, Huang W. An efficient and precise method for generating knockout cell lines based on CRISPR-Cas9 system. Eng Life Sci 2020; 20:585-593. [PMID: 33304232 PMCID: PMC7708952 DOI: 10.1002/elsc.202000032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/07/2020] [Accepted: 08/11/2020] [Indexed: 11/25/2022] Open
Abstract
Although the efficiency and versatility of CRISPR-Cas9 system has been greatly improved over conventional genome editing methods such as zinc finger or TALEN, it is still time-consuming and labor-intensive for screening knockout/knock-in cell clones due to differences of the targeted location or efficacies of guide RNAs (gRNAs). Here, we adapted a targeted knock-in strategy with CRISPR-Cas9 system and characterized the efficiency for generating single or double knockout cell lines. Specifically, a homology-arm based donor cassette consisting of genes encoding a fluorescence protein and antibiotic selection marker driven by a constitutive promoter was co-transfected with a gRNA expressing unit. Based on FACS sorting and antibiotic drug selection, positive cell clones were confirmed by genotyping and at the protein expression level. The results indicated that more than 70% of analyzed clones identified by cell sorting and selection were successfully targeted in both single and double knockout experiments. The procedure takes less than three weeks to obtain knockout cell lines. We believe that this methodology could be applicable and versatile in generating knockout cell clones with high efficiency in most cell lines.
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Affiliation(s)
- Xibin Lu
- Core Research FacilitiesSouthern University of Science and TechnologyShenzhenP. R. China
| | - Yuhan Guo
- Forward Pharmaceuticals Limited CoShenzhenP. R. China
| | - Shu Gu
- Department of BiologySouthern University of Science and TechnologyShenzhenP. R. China
| | - Deng Tan
- Department of BiologySouthern University of Science and TechnologyShenzhenP. R. China
| | - Baoyun Cheng
- Department of BiologySouthern University of Science and TechnologyShenzhenP. R. China
| | - Zhoufang Li
- Core Research FacilitiesSouthern University of Science and TechnologyShenzhenP. R. China
| | - Wei Huang
- Department of BiologySouthern University of Science and TechnologyShenzhenP. R. China
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9
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Tóth E, Varga É, Kulcsár PI, Kocsis-Jutka V, Krausz SL, Nyeste A, Welker Z, Huszár K, Ligeti Z, Tálas A, Welker E. Improved LbCas12a variants with altered PAM specificities further broaden the genome targeting range of Cas12a nucleases. Nucleic Acids Res 2020; 48:3722-3733. [PMID: 32107556 PMCID: PMC7144938 DOI: 10.1093/nar/gkaa110] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 02/07/2020] [Accepted: 02/24/2020] [Indexed: 12/26/2022] Open
Abstract
The widespread use of Cas12a (formerly Cpf1) nucleases for genome engineering is limited by their requirement for a rather long TTTV protospacer adjacent motif (PAM) sequence. Here we have aimed to loosen these PAM constraints and have generated new PAM mutant variants of the four Cas12a orthologs that are active in mammalian and plant cells, by combining the mutations of their corresponding RR and RVR variants with altered PAM specificities. LbCas12a-RVRR showing the highest activity was selected for an in-depth characterization of its PAM preferences in mammalian cells, using a plasmid-based assay. The consensus PAM sequence of LbCas12a-RVRR resembles a TNTN motif, but also includes TACV, TTCV CTCV and CCCV. The D156R mutation in improved LbCas12a (impLbCas12a) was found to further increase the activity of that variant in a PAM-dependent manner. Due to the overlapping but still different PAM preferences of impLbCas12a and the recently reported enAsCas12a variant, they complement each other to provide increased efficiency for genome editing and transcriptome modulating applications.
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Affiliation(s)
- Eszter Tóth
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary
| | - Éva Varga
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Doctoral School of Multidisciplinary Medical Science, University of Szeged, Szeged H-6726, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged H-6726, Hungary
| | - Péter István Kulcsár
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Doctoral School of Multidisciplinary Medical Science, University of Szeged, Szeged H-6726, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged H-6726, Hungary
| | - Virág Kocsis-Jutka
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,ProteoScientia Kft, Cserhátszentiván, H-3066, Hungary
| | - Sarah Laura Krausz
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,School of Ph.D. Studies, Semmelweis University, Budapest, H-1085, Hungary
| | - Antal Nyeste
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged H-6726, Hungary.,ProteoScientia Kft, Cserhátszentiván, H-3066, Hungary
| | | | - Krisztina Huszár
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Biospirál-2006 Kft., Szeged, H-6726, Hungary
| | - Zoltán Ligeti
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Doctoral School of Multidisciplinary Medical Science, University of Szeged, Szeged H-6726, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged H-6726, Hungary
| | - András Tálas
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,School of Ph.D. Studies, Semmelweis University, Budapest, H-1085, Hungary
| | - Ervin Welker
- Institute of Enzymology, Research Centre of Natural Sciences of the Hungarian Academy of Sciences, Budapest H-1117, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged H-6726, Hungary
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10
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Kulcsár PI, Tálas A, Tóth E, Nyeste A, Ligeti Z, Welker Z, Welker E. Blackjack mutations improve the on-target activities of increased fidelity variants of SpCas9 with 5'G-extended sgRNAs. Nat Commun 2020; 11:1223. [PMID: 32144253 PMCID: PMC7060260 DOI: 10.1038/s41467-020-15021-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 02/06/2020] [Indexed: 12/17/2022] Open
Abstract
Increased fidelity mutants of the SpCas9 nuclease constitute the most promising approach to mitigating its off-target effects. However, these variants are effective only in a restricted target space, and many of them are reported to work less efficiently when applied in clinically relevant, pre-assembled, ribonucleoprotein forms. The low tolerance to 5'-extended, 21G-sgRNAs contributes, to a great extent, to their decreased performance. Here, we report the generation of Blackjack SpCas9 variant that shows increased fidelity yet remain effective with 21G-sgRNAs. Introducing Blackjack mutations into previously reported increased fidelity variants make them effective with 21G-sgRNAs and increases their fidelity. Two "Blackjack" nucleases, eSpCas9-plus and SpCas9-HF1-plus are superior variants of eSpCas9 and SpCas9-HF1, respectively, possessing matching on-target activity and fidelity but retaining activity with 21G-sgRNAs. They facilitate the use of existing pooled sgRNA libraries with higher specificity and show similar activities whether delivered as plasmids or as pre-assembled ribonucleoproteins.
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Affiliation(s)
- Péter István Kulcsár
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary.
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, H-6726, Hungary.
- Doctoral School of Multidisciplinary Medical Science, University of Szeged, H-6720, Szeged, Hungary.
| | - András Tálas
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary
- School of Ph.D. Studies, Semmelweis University, Budapest, H-1085, Hungary
| | - Eszter Tóth
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary
| | - Antal Nyeste
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary
| | - Zoltán Ligeti
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary
- Doctoral School of Multidisciplinary Medical Science, University of Szeged, H-6720, Szeged, Hungary
- Gene Design Ltd, Szeged, H-6726, Hungary
| | | | - Ervin Welker
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, H-1117, Hungary.
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, H-6726, Hungary.
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11
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Kovacsics D, Brózik A, Tihanyi B, Matula Z, Borsy A, Mészáros N, Szabó E, Németh E, Fóthi Á, Zámbó B, Szüts D, Várady G, Orbán TI, Apáti Á, Sarkadi B. Precision-engineered reporter cell lines reveal ABCG2 regulation in live lung cancer cells. Biochem Pharmacol 2020; 175:113865. [PMID: 32142727 DOI: 10.1016/j.bcp.2020.113865] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/18/2020] [Indexed: 12/19/2022]
Abstract
Expression of the ABCG2 multidrug transporter is a marker of cancer stem cells and a predictor of recurrent malignant disease. Understanding how human ABCG2 expression is modulated by pharmacotherapy is crucial in guiding therapeutic recommendations and may aid rational drug development. Genome edited reporter cells are useful in investigating gene regulation and visualizing protein activity in live cells but require precise targeting to preserve native regulatory regions. Here, we describe a fluorescent reporter assay that allows the noninvasive assessment of ABCG2 regulation in human lung adenocarcinoma cells. Using CRISPR-Cas9 gene editing coupled with homology-directed repair, we targeted an EGFP coding sequence to the translational start site of ABCG2, generating ABCG2 knock-out and in situ tagged ABCG2 reporter cells. Using the engineered cell lines, we show that ABCG2 is upregulated by a number of anti-cancer medications, HDAC inhibitors, hypoxia-mimicking agents and glucocorticoids, supporting a model in which ABCG2 is under the control of a general stress response. To our knowledge, this is the first description of a fluorescent reporter assay system designed to follow the endogenous regulation of a human ABC transporter in live cells. The information gained may guide therapy recommendations and aid rational drug design.
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Affiliation(s)
- Daniella Kovacsics
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Anna Brózik
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Borbála Tihanyi
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Zsolt Matula
- South-Pest Hospital Centre, National Institute of Hematology and Infectious Diseases, Laboratory of Molecular and Cytogenetics, Budapest, Hungary
| | - Adrienn Borsy
- South-Pest Hospital Centre, National Institute of Hematology and Infectious Diseases, Laboratory of Molecular and Cytogenetics, Budapest, Hungary
| | - Nikolett Mészáros
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Edit Szabó
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Eszter Németh
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Ábel Fóthi
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Boglárka Zámbó
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Dávid Szüts
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - György Várady
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Tamás I Orbán
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Ágota Apáti
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary
| | - Balázs Sarkadi
- Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary.
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12
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Shen W, Zhang J, Geng B, Qiu M, Hu M, Yang Q, Bao W, Xiao Y, Zheng Y, Peng W, Zhang G, Ma L, Yang S. Establishment and application of a CRISPR-Cas12a assisted genome-editing system in Zymomonas mobilis. Microb Cell Fact 2019; 18:162. [PMID: 31581942 PMCID: PMC6777028 DOI: 10.1186/s12934-019-1219-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 09/26/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Efficient and convenient genome-editing toolkits can expedite genomic research and strain improvement for desirable phenotypes. Zymomonas mobilis is a highly efficient ethanol-producing bacterium with a small genome size and desirable industrial characteristics, which makes it a promising chassis for biorefinery and synthetic biology studies. While classical techniques for genetic manipulation are available for Z. mobilis, efficient genetic engineering toolkits enabling rapidly systematic and high-throughput genome editing in Z. mobilis are still lacking. RESULTS Using Cas12a (Cpf1) from Francisella novicida, a recombinant strain with inducible cas12a expression for genome editing was constructed in Z. mobilis ZM4, which can be used to mediate RNA-guided DNA cleavage at targeted genomic loci. gRNAs were then designed targeting the replicons of native plasmids of ZM4 with about 100% curing efficiency for three native plasmids. In addition, CRISPR-Cas12a recombineering was used to promote gene deletion and insertion in one step efficiently and precisely with efficiency up to 90%. Combined with single-stranded DNA (ssDNA), CRISPR-Cas12a system was also applied to introduce minor nucleotide modification precisely into the genome with high fidelity. Furthermore, the CRISPR-Cas12a system was employed to introduce a heterologous lactate dehydrogenase into Z. mobilis with a recombinant lactate-producing strain constructed. CONCLUSIONS This study applied CRISPR-Cas12a in Z. mobilis and established a genome editing tool for efficient and convenient genome engineering in Z. mobilis including plasmid curing, gene deletion and insertion, as well as nucleotide substitution, which can also be employed for metabolic engineering to help divert the carbon flux from ethanol production to other products such as lactate demonstrated in this work. The CRISPR-Cas12a system established in this study thus provides a versatile and powerful genome-editing tool in Z. mobilis for functional genomic research, strain improvement, as well as synthetic microbial chassis development for economic biochemical production.
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Affiliation(s)
- Wei Shen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Jun Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Binan Geng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Mengyue Qiu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Mimi Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Qing Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Weiwei Bao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Yubei Xiao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Yanli Zheng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Wenfang Peng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Guimin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Lixin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Shihui Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province and School of Life Sciences, Hubei University, Wuhan, 430062 China
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Bukhari H, Müller T. Endogenous Fluorescence Tagging by CRISPR. Trends Cell Biol 2019; 29:912-928. [PMID: 31522960 DOI: 10.1016/j.tcb.2019.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/11/2019] [Accepted: 08/12/2019] [Indexed: 01/01/2023]
Abstract
Fluorescent proteins have revolutionized biomedical research as they are easy to use for protein tagging, cope without fixation or permeabilization, and thus, enable live cell imaging in various models. Current methods allow easy and quick integration of fluorescent markers to endogenous genes of interest. In this review, we introduce the three central methods, zinc finger nucleases (ZFNs), transcription activator-like effectors (TALENs), and CRISPR, that have been widely used to manipulate cells or organisms. Focusing on CRISPR technology, we give an overview on homology-directed repair (HDR)-, microhomology-mediated end joining (MMEJ)-, and nonhomologous end joining (NHEJ)-based strategies for the knock-in of markers, figure out recent developments of the technique for highly efficient knock-in, and demonstrate pros and cons. We highlight the unique aspects of fluorescent protein knock-ins and pinpoint specific improvements and perspectives, like the combination of editing with stem cell derived organoid development.
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Affiliation(s)
- Hassan Bukhari
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Molecular Biochemistry, Cell Signalling, Ruhr-University Bochum, Bochum, Germany
| | - Thorsten Müller
- Department of Molecular Biochemistry, Cell Signalling, Ruhr-University Bochum, Bochum, Germany; Institute of Psychiatric Phenomics and Genomics (IPPG), University Hospital, LMU Munich, Munich 80336, Germany.
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14
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Smirnikhina SA, Anuchina AA, Lavrov AV. Ways of improving precise knock-in by genome-editing technologies. Hum Genet 2018; 138:1-19. [DOI: 10.1007/s00439-018-1953-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 10/29/2018] [Indexed: 02/07/2023]
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15
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Wang W, Zheng W, Hu F, He X, Wu D, Zhang W, Liu H, Ma X. Enhanced Biosynthesis Performance of Heterologous Proteins in CHO-K1 Cells Using CRISPR-Cas9. ACS Synth Biol 2018; 7:1259-1268. [PMID: 29683658 DOI: 10.1021/acssynbio.7b00375] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Chinese hamster ovary (CHO) cells are the famous expression system for industrial production of recombinant proteins, such as therapeutic antibodies. However, there still remain bottlenecks in protein quality and weakness in expression efficiency because of the intrinsic genetic properties of the cell. Here we have enhanced biosynthesis performance of heterologous proteins in CHO-K1 cells using CRISPR-Cas9 by editing the genome precisely with two genes for improving ER microenvironment and reinforcing antiapoptotic ability. A linear donor plasmid harboring eGFP-HsQSOX1b and Survivin genes was knocked in specific locus in CHO-K1 genome by the CRISPR-Cas9 RNA guided nucleases via NHEJ with efficiencies of up to 3.85% in the CHO-K1 cell pools following FACS, and the hQSOX1 and hSurvivin genes were integrated into expected genome locus successfully. Compared with control, the antiapoptotic viability of edited CHO-K1 cells was increased by 6.40 times, and the yield has been raised by 5.55 times with GLuc as model protein. The possible molecular mechanisms and pathways of remarkable antiapoptotic ability and protein biosynthesis in modified CHO-K1 cells have been elucidated reasonably. In conclusion, the novel ideas and reliable techniques for obtaining foreign proteins more efficiently in engineered animal cells were very valuable to meet large clinical needs.
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Affiliation(s)
- Wenpeng Wang
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, PR China
| | - Wenyun Zheng
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Fengzhi Hu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Xiujuan He
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Dong Wu
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, PR China
| | - Wenliang Zhang
- Center of Translational Biomedical Research, University of North Carolina at Greensboro, Greensboro, North Carolina 27310, United States
| | - Haipeng Liu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, Fujian, PR China
| | - Xingyuan Ma
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, PR China
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16
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Development of versatile non-homologous end joining-based knock-in module for genome editing. Sci Rep 2018; 8:593. [PMID: 29330493 PMCID: PMC5766535 DOI: 10.1038/s41598-017-18911-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 12/19/2017] [Indexed: 02/02/2023] Open
Abstract
CRISPR/Cas9-based genome editing has dramatically accelerated genome engineering. An important aspect of genome engineering is efficient knock-in technology. For improved knock-in efficiency, the non-homologous end joining (NHEJ) repair pathway has been used over the homology-dependent repair pathway, but there remains a need to reduce the complexity of the preparation of donor vectors. We developed the versatile NHEJ-based knock-in module for genome editing (VIKING). Using the consensus sequence of the time-honored pUC vector to cut donor vectors, any vector with a pUC backbone could be used as the donor vector without customization. Conditions required to minimize random integration rates of the donor vector were also investigated. We attempted to isolate null lines of the VDR gene in human HaCaT keratinocytes using knock-in/knock-out with a selection marker cassette, and found 75% of clones isolated were successfully knocked-in. Although HaCaT cells have hypotetraploid genome composition, the results suggest multiple clones have VDR null phenotypes. VIKING modules enabled highly efficient knock-in of any vectors harboring pUC vectors. Users now can insert various existing vectors into an arbitrary locus in the genome. VIKING will contribute to low-cost genome engineering.
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17
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Kulcsár PI, Tálas A, Huszár K, Ligeti Z, Tóth E, Weinhardt N, Fodor E, Welker E. Crossing enhanced and high fidelity SpCas9 nucleases to optimize specificity and cleavage. Genome Biol 2017; 18:190. [PMID: 28985763 PMCID: PMC6389135 DOI: 10.1186/s13059-017-1318-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 09/11/2017] [Indexed: 12/19/2022] Open
Abstract
Background The propensity for off-target activity of Streptococcus pyogenes Cas9 (SpCas9) has been considerably decreased by rationally engineered variants with increased fidelity (eSpCas9; SpCas9-HF1). However, a subset of targets still generate considerable off-target effects. To deal specifically with these targets, we generated new “Highly enhanced Fidelity” nuclease variants (HeFSpCas9s) containing mutations from both eSpCas9 and SpCas9-HF1 and examined these improved nuclease variants side by side to decipher the factors that affect their specificities and to determine the optimal nuclease for applications sensitive to off-target effects. Results These three increased-fidelity nucleases can routinely be used only with perfectly matching 20-nucleotide-long spacers, a matching 5′ G extension being more detrimental to their activities than a mismatching one. HeFSpCas9 exhibit substantially improved specificity for those targets for which eSpCas9 and SpCas9-HF1 have higher off-target propensity. The targets can also be ranked by their cleavability and off-target effects manifested by the increased fidelity nucleases. Furthermore, we show that the mutations in these variants may diminish the cleavage, but not the DNA-binding, of SpCas9s. Conclusions No single nuclease variant shows generally superior fidelity; instead, for highest specificity cleavage, each target needs to be matched with an appropriate high-fidelity nuclease. We provide here a framework for generating new nuclease variants for targets that currently have no matching optimal nuclease, and offer a simple means for identifying the optimal nuclease for targets in the absence of accurate target-ranking prediction tools. Electronic supplementary material The online version of this article (doi:10.1186/s13059-017-1318-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Péter István Kulcsár
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary.,University of Szeged, Szeged, Hungary
| | - András Tálas
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,School of Ph.D. Studies, Semmelweis University, Budapest, Hungary
| | - Krisztina Huszár
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary.,Gene Design Kft, Szeged, Hungary
| | - Zoltán Ligeti
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,Gene Design Kft, Szeged, Hungary
| | - Eszter Tóth
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Nóra Weinhardt
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary.,University of Szeged, Szeged, Hungary
| | - Elfrieda Fodor
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Ervin Welker
- Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary. .,Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary.
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