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Lee NCO, Petrov NS, Larionov V, Kouprina N. Assembly of Multiple Full-Size Genes or Genomic DNA Fragments on Human Artificial Chromosomes Using the Iterative Integration System. Curr Protoc 2021; 1:e316. [PMID: 34919348 PMCID: PMC8730363 DOI: 10.1002/cpz1.316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Human artificial chromosomes (HACs) are gene delivery vectors that have been used for decades for gene functional studies. HACs have several advantages over viral‐based gene transfer systems, including stable episomal maintenance in a single copy in the cell and the ability to carry up to megabase‐sized genomic DNA segments. We have previously developed the alphoidtetO‐HAC, which has a single gene acceptor loxP site that allows insertion of an individual gene of interest using Chinese hamster ovary (CHO) hybrid cells. The HAC, along with a DNA segment of interest, can then be transferred from donor CHO cells to various recipient cells of interest via microcell‐mediated chromosome transfer (MMCT). Here, we detail a protocol for loading multiple genomic DNA segments or genes into the alphoidtetO‐HAC vector using an iterative integration system (IIS) that utilizes recombinases Cre, ΦC31, and ΦBT. This IIS‐alphoidtetO‐HAC can be used for either serially assembling genomic loci or fragments of a large gene, or for inserting multiple genes into the same artificial chromosome. The insertions are executed iteratively, whereby each round results in the insertion of a new DNA segment of interest. This is accompanied by changes of expression of marker fluorescent proteins, which simplifies screening of correct clones, and changes of selection and counterselection markers, which constitutes an error‐proofing mechanism that removes mis‐incorporated DNA segments. In addition, the IIS‐alphoidtetO‐HAC carrying the genes can be eliminated from the cells, offering the possibility to compare the phenotypes of human cells with and without functional copies of the genes of interest. The resulting HAC molecules may be used to investigate biomedically relevant pathways or the regulation of multiple genes, and to potentially engineer synthetic chromosomes with a specific set of genes of interest. The IIS‐alphoidtetO‐HAC system is expected to be beneficial in creating multiple‐gene humanized models with the purpose of understanding complex multi‐gene genetic disorders. Published 2021. This article is a U.S. Government work and is in the public domain in the USA. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Integration of the first DNA segment of interest into the IIS‐alphoidteto‐HAC Basic Protocol 2: Integration of a second DNA segment of interest into the IIS‐alphoidteto‐HAC Basic Protocol 3: Integration of a third DNA segment of interest into the IIS‐alphoidteto‐HAC Support Protocol: Fluorescence in situ hybridization analysis for the circular IIS‐alphoidtetO‐HAC
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Affiliation(s)
- Nicholas C O Lee
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Nikolai S Petrov
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Liskovykh M, Larionov V, Kouprina N. Highly Efficient Microcell-Mediated Transfer of HACs Containing a Genomic Region of Interest into Mammalian Cells. Curr Protoc 2021; 1:e236. [PMID: 34491634 PMCID: PMC10758282 DOI: 10.1002/cpz1.236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human artificial chromosomes (HACs) are considered promising tools for gene delivery, functional analyses, and gene therapy. HACs have the potential to overcome many of the problems caused by the use of viral-based gene transfer systems, such as limited cloning capacity, lack of copy number control, and insertional mutagenesis during integration into host chromosomes. The recently developed alphoidtetO -HAC has an advantage over other HAC vectors because it can be easily eliminated from dividing cells by inactivation of its conditional kinetochore. This provides a unique control mechanism to study phenotypes induced by a gene or genes carried on the HAC. The alphoidtetO -HAC has a single gene acceptor loxP site that allows insertion of an individual gene of interest or a cluster of genes of up to several Mb in size in Chinese hamster ovary (CHO) hybrid cells. The HACs carrying chromosomal copies of genes can then be transferred from these donor CHO cells to different recipient cells of interest via microcell-mediated chromosome transfer (MMCT). Here, we describe a detailed protocol for loading a gene of interest into the alphoidtetO -HAC vector and for the subsequent transfer of the HAC to recipient cells using an improved MMCT protocol. The original MMCT protocol includes treatment of donor cells with colcemid to induce micronucleation, wherein the HAC becomes surrounded with a nuclear membrane. That step is followed by disarrangement of the actin cytoskeleton using cytochalasin B to help induce microcell formation. The updated MMCT protocol, described here, features the replacement of colcemid and cytochalasin B with TN16 + griseofulvin and latrunculin B, respectively, and the use of collagen/laminin surface coating to promote attachment of metaphase cells to plates during micronuclei induction. These modifications increase the efficiency of HAC transfer to recipient cells ten fold. The improved MMCT protocol has been successfully tested on several recipient cell lines, including human mesenchymal stem cells and mouse embryonic stem cells. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Insertion of a BAC containing a gene of interest into a single loxP loading site of alphoidtetO -HAC in hamster CHO cells Basic Protocol 2: Microcell-mediated chromosome transfer from donor hamster CHO cells to mammalian cells.
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Affiliation(s)
- Mikhail Liskovykh
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Kouprina N, Larionov V. TAR Cloning: Perspectives for Functional Genomics, Biomedicine, and Biotechnology. Mol Ther Methods Clin Dev 2019; 14:16-26. [PMID: 31276008 PMCID: PMC6586605 DOI: 10.1016/j.omtm.2019.05.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Completion of the human genome sequence and recent advances in engineering technologies have enabled an unprecedented level of understanding of DNA variations and their contribution to human diseases and cellular functions. However, in some cases, long-read sequencing technologies do not allow determination of the genomic region carrying a specific mutation (e.g., a mutation located in large segmental duplications). Transformation-associated recombination (TAR) cloning allows selective, most accurate, efficient, and rapid isolation of a given genomic fragment or a full-length gene from simple and complex genomes. Moreover, this method is the only way to simultaneously isolate the same genomic region from multiple individuals. As such, TAR technology is currently in a leading position to create a library of the individual genes that comprise the human genome and physically characterize the sites of chromosomal alterations (copy number variations [CNVs], inversions, translocations) in the human population, associated with the predisposition to different diseases, including cancer. It is our belief that such a library and analysis of the human genome will be of great importance to the growing field of gene therapy, new drug design methods, and genomic research. In this review, we detail the motivation for TAR cloning for human genome studies, biotechnology, and biomedicine, discuss the recent progress of some TAR-based projects, and describe how TAR technology in combination with HAC (human artificial chromosome)-based and CRISPR-based technologies may contribute in the future.
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Affiliation(s)
- Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, MD 20892, USA
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, MD 20892, USA
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4
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Greene A, Pascarelli K, Broccoli D, Perkins E. Engineering Synthetic Chromosomes by Sequential Loading of Multiple Genomic Payloads over 100 Kilobase Pairs in Size. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2019; 13:463-473. [PMID: 31193384 PMCID: PMC6527818 DOI: 10.1016/j.omtm.2019.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 04/24/2019] [Indexed: 11/22/2022]
Abstract
Gene delivery vehicles currently in the clinic for treatment of monogenic disorders lack sufficient carrying capacity to efficiently address complex polygenic diseases. Thus, to engineer multifaceted genetic circuits for bioengineering human cells as a therapeutic option for polygenic diseases, we require new tools that are currently in their infancy. Mammalian artificial chromosomes, or synthetic chromosomes, represent a viable approach for delivery of large genetic payloads that are mitotically stable and remain independent of the host genome. Previously, we described a mammalian synthetic chromosome platform, termed the ACE system, that requires a single unidirectional integrase for the introduction of multiple genes onto the ACE platform chromosome. In this report, we provide a proof of concept that the ACE synthetic chromosome bioengineering platform is amenable to sequential delivery of off-the-shelf large genomic fragments. Specifically, large genomic clones spanning the human solute carrier family 2, facilitated glucose transporter member 1 (SLC2A1 or GLUT1, 169 kbp), and human monocarboxylate transporter 1 (SLC16A1 or MCT1, 144 kbp) genetic loci were engineered onto the ACE platform and demonstrated to express and correctly splice both gene transcripts. Thus, the ACE system provides a facile and tractable engineering platform for the development of gene-based therapeutic agents targeting polygenic diseases.
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Affiliation(s)
- Amy Greene
- Department of Medical Sciences, Mercer University School of Medicine, Savannah, GA 31404, USA
- SynPloid Biotek, LLC, Savannah, GA 31404, USA
| | | | - Dominique Broccoli
- Department of Medical Sciences, Mercer University School of Medicine, Savannah, GA 31404, USA
- SynPloid Biotek, LLC, Savannah, GA 31404, USA
| | - Edward Perkins
- Department of Medical Sciences, Mercer University School of Medicine, Savannah, GA 31404, USA
- SynPloid Biotek, LLC, Savannah, GA 31404, USA
- Corresponding author: Edward Perkins, Mercer University School of Medicine, Savannah, GA 31404, USA.
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Kouprina N, Petrov N, Molina O, Liskovykh M, Pesenti E, Ohzeki JI, Masumoto H, Earnshaw WC, Larionov V. Human Artificial Chromosome with Regulated Centromere: A Tool for Genome and Cancer Studies. ACS Synth Biol 2018; 7:1974-1989. [PMID: 30075081 PMCID: PMC6154217 DOI: 10.1021/acssynbio.8b00230] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Since their description in the late 1990s, Human Artificial Chromosomes (HACs) bearing functional kinetochores have been considered as promising systems for gene delivery and expression. More recently a HAC assembled from a synthetic alphoid DNA array has been exploited in studies of centromeric chromatin and in assessing the impact of different epigenetic modifications on kinetochore structure and function in human cells. This HAC was termed the alphoidtetO-HAC, as the synthetic monomers each contained a tetO sequence in place of the CENP-B box that can be targeted specifically with tetR-fusion proteins. Studies in which the kinetochore chromatin of the alphoidtetO-HAC was specifically modified, revealed that heterochromatin is incompatible with centromere function and that centromeric transcription is important for centromere assembly and maintenance. In addition, the alphoidtetO-HAC was modified to carry large gene inserts that are expressed in target cells under conditions that recapitulate the physiological regulation of endogenous loci. Importantly, the phenotypes arising from stable gene expression can be reversed when cells are "cured" of the HAC by inactivating its kinetochore in proliferating cell populations, a feature that provides a control for phenotypic changes attributed to expression of HAC-encoded genes. AlphoidtetO-HAC-based technology has also been used to develop new drug screening and assessment strategies to manipulate the CIN phenotype in cancer cells. In summary, the alphoidtetO-HAC is proving to be a versatile tool for studying human chromosome transactions and structure as well as for genome and cancer studies.
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Affiliation(s)
- Natalay Kouprina
- Developmental
Therapeutics Branch, National Cancer Institute,
NIH, Bethesda, Maryland 20892, United
States,E-mail: . Tel: +1-240-760-7325
| | - Nikolai Petrov
- Developmental
Therapeutics Branch, National Cancer Institute,
NIH, Bethesda, Maryland 20892, United
States
| | - Oscar Molina
- Josep
Carreras Leukaemia Research Institute, School of Medicine, University
of Barcelona, Casanova 143, 08036 Barcelona, Spain
| | - Mikhail Liskovykh
- Developmental
Therapeutics Branch, National Cancer Institute,
NIH, Bethesda, Maryland 20892, United
States
| | - Elisa Pesenti
- Wellcome
Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland
| | - Jun-ichirou Ohzeki
- Laboratory
of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818d Japan
| | - Hiroshi Masumoto
- Laboratory
of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818d Japan,E-mail: . Tel: +81-438-52-395
| | - William C. Earnshaw
- Wellcome
Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland,E-mail: . Tel: +44-(0)131-650-7101
| | - Vladimir Larionov
- Developmental
Therapeutics Branch, National Cancer Institute,
NIH, Bethesda, Maryland 20892, United
States,E-mail: . Tel: +1-240-760-7325
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Lee NCO, Kim JH, Petrov NS, Lee HS, Masumoto H, Earnshaw WC, Larionov V, Kouprina N. Method to Assemble Genomic DNA Fragments or Genes on Human Artificial Chromosome with Regulated Kinetochore Using a Multi-Integrase System. ACS Synth Biol 2018; 7:63-74. [PMID: 28799737 PMCID: PMC5778389 DOI: 10.1021/acssynbio.7b00209] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
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The production of cells capable of carrying multiple transgenes
to Mb-size genomic loci has multiple applications in biomedicine and
biotechnology. In order to achieve this goal, three key steps are
required: (i) cloning of large genomic segments; (ii) insertion of
multiple DNA blocks at a precise location and (iii) the capability
to eliminate the assembled region from cells. In this study, we designed
the iterative integration system (IIS) that utilizes recombinases
Cre, ΦC31 and ΦBT1, and combined it with a human artificial
chromosome (HAC) possessing a regulated kinetochore (alphoidtetO-HAC). We have demonstrated that the IIS-alphoidtetO-HAC
system is a valuable genetic tool by reassembling a functional gene
from multiple segments on the HAC. IIS-alphoidtetO-HAC
has several notable advantages over other artificial chromosome-based
systems. This includes the potential to assemble an unlimited number
of genomic DNA segments; a DNA assembly process that leaves only a
small insertion (<60 bp) scar between adjacent DNA, allowing genes
reassembled from segments to be spliced correctly; a marker exchange
system that also changes cell color, and counter-selection markers
at each DNA insertion step, simplifying selection of correct clones;
and presence of an error proofing mechanism to remove cells with misincorporated
DNA segments, which improves the integrity of assembly. In addition,
the IIS-alphoidtetO-HAC carrying a locus of interest is
removable, offering the unique possibility to revert the cell line
to its pretransformed state and compare the phenotypes of human cells
with and without a functional copy of a gene(s). Thus, IIS-alphoidtetO-HAC allows investigation of complex biomedical pathways,
gene(s) regulation, and has the potential to engineer synthetic chromosomes
with a predetermined set of genes.
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Affiliation(s)
- Nicholas C. O. Lee
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
| | - Jung-Hyun Kim
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
| | - Nikolai S. Petrov
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
| | - Hee-Sheung Lee
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
| | - Hiroshi Masumoto
- Laboratory of Cell Engineering, Department of Frontier Research, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, Chiba 292-0818, Japan
| | - William C. Earnshaw
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, Scotland
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
| | - Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, Bethesda, Maryland 20892, United States
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Moving toward a higher efficiency of microcell-mediated chromosome transfer. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 3:16043. [PMID: 27382603 PMCID: PMC4916947 DOI: 10.1038/mtm.2016.43] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 03/21/2016] [Accepted: 04/27/2016] [Indexed: 12/24/2022]
Abstract
Microcell-mediated chromosome transfer (MMCT) technology enables individual mammalian chromosomes, megabase-sized chromosome fragments, or mammalian artificial chromosomes that include human artificial chromosomes (HACs) and mouse artificial chromosomes (MACs) to be transferred from donor to recipient cells. In the past few decades, MMCT has been applied to various studies, including mapping the genes, analysis of chromosome status such as aneuploidy and epigenetics. Recently, MMCT was applied to transfer MACs/HACs carrying entire chromosomal copies of genes for genes function studies and has potential for regenerative medicine. However, a safe and efficient MMCT technique remains an important challenge. The original MMCT protocol includes treatment of donor cells by Colcemid to induce micronucleation, where each chromosome becomes surrounded with a nuclear membrane, followed by disarrangement of the actin cytoskeleton using Cytochalasin B to help induce microcells formation. In this study, we modified the protocol and demonstrated that replacing Colcemid and Cytochalasin B with TN-16 + Griseofulvin and Latrunculin B in combination with a Collage/Laminin surface coating increases the efficiency of HAC transfer to recipient cells by almost sixfold and is possibly less damaging to HAC than the standard MMCT method. We tested the improved MMCT protocol on four recipient cell lines, including human mesenchymal stem cells and mouse embryonic stem cells that could facilitate the cell engineering by HACs.
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Oshimura M, Uno N, Kazuki Y, Katoh M, Inoue T. A pathway from chromosome transfer to engineering resulting in human and mouse artificial chromosomes for a variety of applications to bio-medical challenges. Chromosome Res 2015; 23:111-33. [PMID: 25657031 PMCID: PMC4365188 DOI: 10.1007/s10577-014-9459-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Microcell-mediated chromosome transfer (MMCT) is a technique to transfer a chromosome from defined donor cells into recipient cells and to manipulate chromosomes as gene delivery vectors and open a new avenue in somatic cell genetics. However, it is difficult to uncover the function of a single specific gene via the transfer of an entire chromosome or fragment, because each chromosome or fragment contains a set of numerous genes. Thus, alternative tools are human artificial chromosome (HAC) and mouse artificial chromosome (MAC) vectors, which can carry a gene or genes of interest. HACs/MACs have been generated mainly by either a "top-down approach" (engineered creation) or a "bottom-up approach" (de novo creation). HACs/MACs with one or more acceptor sites exhibit several characteristics required by an ideal gene delivery vector, including stable episomal maintenance and the capacity to carry large genomic loci plus their regulatory elements, thus allowing the physiological regulation of the introduced gene in a manner similar to that of native chromosomes. The MMCT technique is also applied for manipulating HACs and MACs in donor cells and delivering them to recipient cells. This review describes the lessons learned and prospects identified from studies on the construction of HACs and MACs, and their ability to drive exogenous gene expression in cultured cells and transgenic animals via MMCT. New avenues for a variety of applications to bio-medical challenges are also proposed.
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Affiliation(s)
- Mitsuo Oshimura
- Chromosome Engineering Research Center, Tottori University, 86 Nishi-cho, Yonago, Tottori, 683-8503, Japan,
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Katona RL. Human artificial chromosomes for future biomedicine. Cell Cycle 2015; 14:1494. [PMID: 25928730 DOI: 10.1080/15384101.2015.1032647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- Robert L Katona
- a Institute of Genetics; Biological Research Centre; Hungarian Academy of Sciences ; Szeged , Hungary
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Katona RL. De novo formed satellite DNA-based mammalian artificial chromosomes and their possible applications. Chromosome Res 2015; 23:143-57. [DOI: 10.1007/s10577-014-9458-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Suzuki T, Kazuki Y, Oshimura M, Hara T. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome. PLoS One 2014; 9:e110404. [PMID: 25303219 PMCID: PMC4193884 DOI: 10.1371/journal.pone.0110404] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 09/15/2014] [Indexed: 11/19/2022] Open
Abstract
Human artificial chromosomes (HACs) are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV) into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system) via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.
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Affiliation(s)
- Teruhiko Suzuki
- Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
- * E-mail:
| | - Yasuhiro Kazuki
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
| | - Mitsuo Oshimura
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
| | - Takahiko Hara
- Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
- Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Tokyo, Japan
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