70 research outputs found
Refined human artificial chromosome vectors for gene therapy and animal transgenesis
Human artificial chromosomes (HACs) have several advantages as gene therapy vectors, including stable episomal maintenance, and the ability to carry large gene inserts. We previously developed HAC vectors from the normal human chromosomes using a chromosome engineering technique. However, endogenous genes were remained in these HACs, limiting their therapeutic applications. In this study, we refined a HAC vector without endogenous genes from human chromosome 21 in homologous recombination-proficient chicken DT40 cells. The HAC was physically characterized using a transformation-associated recombination (TAR) cloning strategy followed by sequencing of TAR-bacterial artificial chromosome clones. No endogenous genes were remained in the HAC. We demonstrated that any desired gene can be cloned into the HAC using the Cre-loxP system in Chinese hamster ovary cells, or a homologous recombination system in DT40 cells. The HAC can be efficiently transferred to other type of cells including mouse ES cells via microcell-mediated chromosome transfer. The transferred HAC was stably maintained in vitro and in vivo. Furthermore, tumor cells containing a HAC carrying the suicide gene, herpes simplex virus thymidine kinase (HSV-TK), were selectively killed by ganciclovir in vitro and in vivo. Thus, this novel HAC vector may be useful not only for gene and cell therapy, but also for animal transgenesis
Mild electrical stimulation with heat shock guides differentiation of embryonic stem cells into Pdx1-expressing cells within the definitive endoderm
A novel in vitro system for analyzing parental allele-specific histone acetylation in genomic imprinting
Nullipotent teratocarcinoma cells acquire the pluripotency for differentiation by fusion with somatic cells.
Interferon-induced transcription of a major histocompatibility class I gene accompanies binding of inducible nuclear factors to the interferon consensus sequence.
Binding of multiple nuclear factors to the 5' upstream regulatory element of the murine major histocompatibility class I gene.
Regulation of mouse CYP1A1 gene expression by dioxin: requirement of two cis-acting elements during induction.
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