Tae Sub Park

The derivation of germ cells from human embryonic stem cells (hESCs) or human induced pluripotent stem (hIPS) cells represents a desirable experimental model and potential strategy for treating infertility. In the current study, we developed a triple biomarker assay for identifying and isolating human primordial germ cells (PGCs) by first evaluating human PGC formation during the first trimester in vivo. Next, we applied this technology to characterizing in vitro derived PGCs (iPGCs) from plurip

Genetically modified animals are used for industrial applications as well as scientific research, and studies on these animals contribute to a better understanding of biological mechanisms. Gene targeting techniques have been developed to edit specific gene loci in the genome, but the conventional strategy of homologous recombination with a gene-targeted vector has low efficiency and many technical complications. Here, we generated specific gene knockout chickens through the use of transcription

Embryonic germ (EG) cell lines established from primordial germ cells (PGCs) are undifferentiated and pluripotent stem cells. To date, EG cells with proven germ-line transmission have been completely established only in the mouse with embryonic stem (ES) cells. We isolated PGCs from 5.5-day-old (stage 28) chicken embryonic gonads and established a putative chicken EG cell line with EG culture medium supplemented with stem cell factor (SCF), leukemia inhibitory factor (LIF), basic fibroblast grow

Over the past two decades numerous reports have demonstrated that the genetic modification of poultry genomes has great potential for improving poultry production; moreover, it may be used as a powerful tool for the production of industrial proteins. To date, transgenic techniques have been established for generating transgenic birds that express recombinant human proteins in hen eggs, as well as tissue-specific genes as an animal model. The production of transgenic birds is a promising approach

Germ cell differentiation in reverse-sexed reproductive organs and interspecies germ line chimeras provides insight into the mechanism of germ cell development and represents a useful tool for conservation of endangered birds. We investigated the migration and survival capacity of male chicken primordial germ cells (PGCs) in female chicken embryos and in quail and Korean ring-necked pheasant embryos of both sexes. Interestingly, the PGCs were successfully reintroduced in all cases. Furthermore,

Genetic modification enables modification of target genes or genome structure in livestock and experimental animals. These technologies have not only advanced bioscience but also improved agricultural productivity. To introduce a foreign transgene, the piggyBac transposon element/transposase system could be used for production of transgenic animals and specific target protein-expressing animal cells. In addition, the clustered regularly interspaced short palindromic repeat-CRISPR associated prot

NANOG, as a transcription factor, plays a key role in maintaining pluripotency in higher vertebrates. Thus, NANOG gene expression is a critical index for the transition from somatic cells to the pluripotent stage. Here, we established chicken knock-in DF1 cells in which the red fluorescent protein (RFP) gene was specifically inserted into the transcriptional start site of the NANOG gene through the CRISPR‒Cas9 (clustered regularly interspaced short palindromic repeat-CRISPR associated protein 9)

Avian germ cell

Embryonic germ (EG) cell lines established from primordial germ cells (PGCs) are undifferentiated and pluripotent stem cells. To date, EG cells with proven germ-line transmission have been completely established only in the mouse with embryonic stem (ES) cells. We isolated PGCs from 5.5-day-old (stage 28) chicken embryonic gonads and established a putative chicken EG cell line with EG culture medium supplemented with stem cell factor (SCF), leukemia inhibitory factor (LIF), basic fibroblast grow

Transgene induction or replacement cassette systems in avian cells can be applied in functional genomics studies of specific genes and adapted further for efficient generation of transgenic poultry to modulate target gene expression.

A bioreactor can be used for mass production of therapeutic proteins and other bioactive substances. Although various methods have been developed using microorganisms and animal cells, advanced strategies are needed for the efficient production of biofunctional proteins. In microorganisms, post-translational glycosylation and modification are not performed properly, while animal cell systems require more time and expense. To overcome these problems, new methods using products from transgenic ani

Our results demonstrate that the CRISPR/Cas9 technical platform with chicken PGCs facilitates the production of specific genome-edited chickens for basic research as well as practical applications.

The P-element-induced wimpy testis (PIWI) protein, which associates with small non-coding RNAs, is responsible for maintaining the integrity of germ cells and stem cells. Thus, transcriptional regulation of PIWI is critical for its effective functional modulation. In this study, we identified the promoter region of the PIWI homolog in chicken (CIWI), and investigated the transcriptional regulatory elements that control expression of CIWI in chicken primordial germ cells (PGCs). We constructed a

Birds have a distinguished history as a model system in the biosciences. Recent developments in genetic modification technologies, including the transposon-transposase and CRISPR/Cas9 systems, are expected to revolutionize genomic research when applied to avian species Based on the methods of somatic cell nuclear transfer (SCNT) for animal cloning and direct injection into one-cell-stage embryo, numerous CRISPR/Cas9-mediated knockout and knock-in animals have been successfully generated, particu