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human artificial chromosome HAC

Toru Takenaka, Kanako Kazuki, Naomoto Harada, Jiro Kuze, Masato Chiba, Takahiro Iwao, Tamihide Matsunaga, Satoshi Abe, Mitsuo Oshimura, Yasuhiro Kazuki
The Caco-2 cells co-expressing cytochrome P450 (CYP) 3A4 and NADPH-cytochrome P450 reductase (CPR) were developed using a human artificial chromosome (HAC) vector. The CYP3A4 and CPR genes were cloned into the HAC vector in CHO cells using the Cre-loxP system, and the microcell-mediated chromosome transfer technique was used to transfer the CYP3A4-CPR-HAC vector to Caco-2 cells. After seeding onto semipermeable culture inserts, the CYP3A4-CPR-HAC/Caco-2 cells were found to form tight monolayers, similar to the parental cells, as demonstrated by the high transepithelial electrical resistance (TEER) value and comparable permeability of non-CYP3A4 substrates between parent and CYP3A4-CPR-HAC/Caco-2 cell monolayers...
August 26, 2016: Drug Metabolism and Pharmacokinetics
David M Brown, Yujia A Chan, Prashant J Desai, Peter Grzesik, Lauren M Oldfield, Sanjay Vashee, Jeffrey C Way, Pamela A Silver, John I Glass
The delivery of large DNA vectors (>100 000 bp) remains a limiting step in the engineering of mammalian cells and the development of human artificial chromosomes (HACs). Yeast is commonly used to assemble genetic constructs in the megabase size range, and has previously been used to transfer constructs directly into cultured cells. We improved this method to efficiently deliver large (1.1 Mb) synthetic yeast centromeric plasmids (YCps) to cultured cell lines at rates similar to that of 12 kb YCps. Synchronizing cells in mitosis improved the delivery efficiency by 10-fold and a statistical design of experiments approach was employed to boost the vector delivery rate by nearly 300-fold from 1/250 000 to 1/840 cells, and subsequently optimize the delivery process for multiple mammalian, avian, and insect cell lines...
December 15, 2016: Nucleic Acids Research
Ltk Do, M Wittayarat, T Terazono, Y Sato, M Taniguchi, F Tanihara, T Takemoto, Y Kazuki, K Kazuki, M Oshimura, T Otoi
The current applications for cat cloning include production of models for the study of human and animal diseases. This study was conducted to investigate the optimal fusion protocol on in vitro development of transgenic cloned cat embryos by comparing duration of electric pulse. Cat fibroblast cells containing a human artificial chromosome (HAC) vector were used as genetically modified nuclear donor cells. Couplets were fused and activated simultaneously with a single DC pulse of 3.0 kV/cm for either 30 or 60 μs...
December 2016: Reproduction in Domestic Animals, Zuchthygiene
Mikhail Liskovykh, Nicholas Co Lee, Vladimir Larionov, Natalay Kouprina
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...
2016: Molecular Therapy. Methods & Clinical Development
Teruhiko Suzuki, Yasuhiro Kazuki, Mitsuo Oshimura, Takahiko Hara
Microcell-mediated chromosome transfer (MMCT) is an essential step for introducing chromosomes from donor cells to recipient cells. MMCT allows not only for genetic/epigenetic analysis of specific chromosomes, but also for utilization of human and mouse artificial chromosomes (HACs/MACs) as gene delivery vectors. Although the scientific demand for genome scale analyses is increasing, the poor transfer efficiency of the current method has hampered the application of chromosome engineering technology. Here, we developed a highly efficient chromosome transfer method, called retro-MMCT, which is based on Chinese hamster ovary cells expressing envelope proteins derived from ecotropic or amphotropic murine leukemia viruses...
2016: PloS One
Sarine Markossian, Alexei Arnaoutov, Nakhle S Saba, Vladimir Larionov, Mary Dasso
Most solid tumors are aneuploid, carrying an abnormal number of chromosomes, and they frequently missegregate whole chromosomes in a phenomenon termed chromosome instability (CIN). While CIN can be provoked through disruption of numerous mitotic pathways, it is not clear which of these mechanisms are most critical, or whether alternative mechanisms could also contribute significantly in vivo. One difficulty in determining the relative importance of candidate CIN regulators has been the lack of a straightforward, quantitative assay for CIN in live human cells: While gross mitotic abnormalities can be detected visually, moderate levels of CIN may not be obvious, and are thus problematic to measure...
July 2, 2016: Cell Cycle
Jung-Hyun Kim, Hee-Sheung Lee, Nicholas C O Lee, Nikolay V Goncharov, Vadim Kumeiko, Hiroshi Masumoto, William C Earnshaw, Natalay Kouprina, Vladimir Larionov
Accumulating data indicates that chromosome instability (CIN) common to cancer cells can be used as a target for cancer therapy. At present the rate of chromosome mis-segregation is quantified by laborious techniques such as coupling clonal cell analysis with karyotyping or fluorescence in situ hybridization (FISH). Recently, a novel assay was developed based on the loss of a non-essential human artificial chromosome (HAC) carrying a constitutively expressed EGFP transgene ("loss of signal" assay). Using this system, anticancer drugs can be easily ranked on by their effect on HAC loss...
March 22, 2016: Oncotarget
Hee-Sheung Lee, Nicholas C O Lee, Natalay Kouprina, Jung-Hyun Kim, Alex Kagansky, Susan Bates, Jane B Trepel, Yves Pommier, Dan Sackett, Vladimir Larionov
Whole chromosomal instability (CIN), manifested as unequal chromosome distribution during cell division, is a distinguishing feature of most cancer types. CIN is generally considered to drive tumorigenesis, but a threshold level exists whereby further increases in CIN frequency in fact hinder tumor growth. While this attribute is appealing for therapeutic exploitation, drugs that increase CIN beyond this therapeutic threshold are currently limited. In our previous work, we developed a quantitative assay for measuring CIN based on the use of a nonessential human artificial chromosome (HAC) carrying a constitutively expressed EGFP transgene...
February 15, 2016: Cancer Research
Nuno M C Martins, Jan H Bergmann, Nobuaki Shono, Hiroshi Kimura, Vladimir Larionov, Hiroshi Masumoto, William C Earnshaw
Centromeres are characterized by the centromere-specific H3 variant CENP-A, which is embedded in chromatin with a pattern characteristic of active transcription that is required for centromere identity. It is unclear how centromeres remain transcriptionally active despite being flanked by repressive pericentric heterochromatin. To further understand centrochromatin's response to repressive signals, we nucleated a Polycomb-like chromatin state within the centromere of a human artificial chromosome (HAC) by tethering the methyltransferase EZH2...
January 1, 2016: Molecular Biology of the Cell
Nobuaki Shono, Jun-ichirou Ohzeki, Koichiro Otake, Nuno M C Martins, Takahiro Nagase, Hiroshi Kimura, Vladimir Larionov, William C Earnshaw, Hiroshi Masumoto
Although it is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity, the pathways leading to the formation and maintenance of centromere chromatin remain unclear. We previously generated human artificial chromosomes (HACs) whose centromeres contain a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator (alphoid(tetO)). We also obtained cell lines bearing the alphoid(tetO) array at ectopic integration sites on chromosomal arms...
December 15, 2015: Journal of Cell Science
Yasuhiro Watanabe, Yasuhiro Kazuki, Kanako Kazuki, Mitsutaka Ebiki, Mami Nakanishi, Kazuomi Nakamura, Miho Yoshida Yamakawa, Hiroyuki Hosokawa, Tetsuya Ohbayashi, Mitsuo Oshimura, Kenji Nakashima
A human artificial chromosome (HAC) is maintained as an episome within a cell and avoids random integration into the host genome. It can transfer multiple and/or large transgenes along with their regulatory elements thereby resembling native chromosomes. Using this HAC system, we established mesenchymal stem cells (MSCs) that simultaneously expressed hepatocyte growth factor, glial cell line-derived neurotrophic factor, and insulin-like growth factor 1, termed HAC-MSCs. This cell line provides an opportunity for stable transplantation and thorough analyses...
2015: Molecular Therapy. Nucleic Acids
Hiroaki Matsushita, Akiko Sano, Hua Wu, Zhongde Wang, Jin-An Jiao, Poothappillai Kasinathan, Eddie J Sullivan, Yoshimi Kuroiwa
Large-scale production of fully human IgG (hIgG) or human polyclonal antibodies (hpAbs) by transgenic animals could be useful for human therapy. However, production level of hpAbs in transgenic animals is generally very low, probably due to the fact that evolutionarily unique interspecies-incompatible genomic sequences between human and non-human host species may impede high production of fully hIgG in the non-human environment. To address this issue, we performed species-specific human artificial chromosome (HAC) engineering and tested these engineered HAC in cattle...
2015: PloS One
Masaharu Hiratsuka, Kana Ueda, Narumi Uno, Katsuhiro Uno, Sayaka Fukuhara, Hajime Kurosaki, Shoko Takehara, Mitsuhiko Osaki, Yasuhiro Kazuki, Yoshikazu Kurosawa, Takafumi Nakamura, Motonobu Katoh, Mitsuo Oshimura
BACKGROUND: Human artificial chromosome (HAC) vectors have some unique characteristics as compared with conventional vectors, carrying large transgenes without size limitation, showing persistent expression of transgenes, and existing independently from host genome in cells. With these features, HACs are expected to be promising vectors for modifications of a variety of cell types. However, the method of introduction of HACs into target cells is confined to microcell-mediated chromosome transfer (MMCT), which is less efficient than other methods of vector introduction...
2015: BMC Biotechnology
Artem V Kononenko, Nicholas C O Lee, Mikhail Liskovykh, Hiroshi Masumoto, William C Earnshaw, Vladimir Larionov, Natalay Kouprina
Human artificial chromosome (HAC)-based vectors represent an alternative technology for gene delivery and expression with a potential to overcome the problems caused by virus-based vectors. The recently developed alphoid(tetO)-HAC has an advantage over other HAC vectors because it can be easily eliminated from cells by inactivation of the HAC kinetochore via binding of chromatin modifiers, tTA or tTS, to its centromeric tetO sequences. This provides a unique control for phenotypes induced by genes loaded into the HAC...
May 19, 2015: Nucleic Acids Research
Mikhail Liskovykh, Sergey Ponomartsev, Elena Popova, Michael Bader, Natalay Kouprina, Vladimir Larionov, Natalia Alenina, Alexey Tomilin
De novo assembled alphoid(tetO)-type human artificial chromosomes (HACs) represent a novel promising generation of high capacity episomal vectors. Their function and persistence, and any adverse effects, in various cell types in live animals, have not, however, been explored. In this study we transferred the alphoid(tetO)-HAC into mouse ES cells and assessed whether the presence of this extra chromosome affects their pluripotent properties. Alphoid(tetO)-HAC-bearing ES cells were indistinguishable from their wild-type counterparts: they retained self-renewal potential and full capacity for multilineage differentiation during mouse development, whereas the HAC itself was mitotically and transcriptionally stable during this process...
2015: Cell Cycle
Jun-ichirou Ohzeki, Vladimir Larionov, William C Earnshaw, Hiroshi Masumoto
The centromere is a specialized chromosomal locus required for accurate chromosome segregation. A specific histone H3 variant, CENP-A, assembles at centromeres. CENP-A is required for kinetochore protein assembly and is an epigenetic marker for the maintenance of a functional centromere. Human CENP-A chromatin normally assembles on α-satellite DNA (alphoid DNA), a centromeric repetitive sequence. Using alphoid DNA arrays, human artificial chromosomes (HACs) have been constructed in human HT1080 cells and used to dissect the requirements for CENP-A assembly on DNA sequence...
February 2015: Chromosome Research
Mitsuo Oshimura, Narumi Uno, Yasuhiro Kazuki, Motonobu Katoh, Toshiaki Inoue
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...
February 2015: Chromosome Research
Daniela Moralli, Zoia L Monaco
De novo artificial chromosomes expressing genes have been generated in human embryonic stem cells (hESc) and are maintained following differentiation into other cell types. Human artificial chromosomes (HAC) are small, functional, extrachromosomal elements, which behave as normal chromosomes in human cells. De novo HAC are generated following delivery of alpha satellite DNA into target cells. HAC are characterized by high levels of mitotic stability and are used as models to study centromere formation and chromosome organisation...
February 2015: Chromosome Research
Yoshinori Hasegawa, Tomoyuki Ishikura, Takanori Hasegawa, Takashi Watanabe, Junpei Suzuki, Manabu Nakayama, Yoshiaki Okamura, Tuneko Okazaki, Haruhiko Koseki, Osamu Ohara, Masashi Ikeno, Hiroshi Masumoto
The human artificial chromosome (HAC) vector is a promising tool to improve the problematic suppression and position effects of transgene expression frequently seen in transgenic cells and animals produced by conventional plasmid or viral vectors. We generated transgenic mice maintaining a single HAC vector carrying two genomic bacterial artificial chromosomes (BACs) from human HLA-DR loci (DRA and DRB1). Both transgenes on the HAC in transgenic mice exhibited tissue-specific expression in kidney, liver, lung, spleen, lymph node, bone marrow, and thymus cells in RT-PCR analysis...
March 2015: Chromosoma
Teruhiko Suzuki, Yasuhiro Kazuki, Mitsuo Oshimura, Takahiko Hara
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...
2014: PloS One
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