• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.4
• /
• pp.482-485
• /
• 2006

Korean native goats have lived on the Korean peninsula for more than 2,000 years and are regarded as a valuable genetic resource for the world. As an initial step to investigate the genetic structures of this breed, phylogenetic analysis and calculation of genetic diversities have been performed using mitochondrial DNA (mtDNA) sequence variations. A total of 19 Korean native goats were grouped into six haplotypes and the large majority of haplotypes were present in 13 animals. All mtDNA of these Korean goats belonged to the mitochondrial (mt) lineage A and revealed remarkably small genetic distances within the population when compared with other Asian goat populations, indicating less genetic variation in the Korean native goats. These results indicate high-inbred status of the Korean native goats and will influence breeding and conservation strategies adopted for this breed.

• Korean Journal of Animal Reproduction
• /
• v.19 no.4
• /
• pp.283-291
• /
• 1996

Transgenic animal을 응용할 수 있는 분야에서는 이식유전자의 기능을 정확하게 규명하고 이를 바탕으로 실질적인 유전적인 개량을 이루기 위해서 이식유전자의 발현을 조절할 수 있는 정교한 system이 필요하다. 유전자의 미세주입법에 의해 transgenic animal을 생산할 수 있는데 이용되고 있는 tissue-specific promoter에 의한 이식유전자의 발현조절은 필요로 하는 시기나 양 등을 인위적으로 조절하고자 하는데 한계점을 갖고 있다. 이러한 이식유전자 발현의 문제점을 극복하기 위해 효모의 recombinase나 미생물의 repressor 단백질과 이들의 binding site인 operator sequence를 이용하여 인위적으로 이식유전자의 발현을 조절할 수 있는 system이 개발되고 있다. Cre/loxP system은 site-specific recombination에 의해 DNA sequence를 제거함으로서 이식유전자의 발현을 조절할 수 있다. 이식유전자 발현의 장소와 양을 조절하기 위해서는 미생물이 이용하고 있는 repressor와 이들의 operator sequence를 적용하여 ligand binary system이 개발되었다. Lac repressor system에서는 isopropyl-$\beta$-D-thiogalactoside (IPTG)가 이식유전자 발현을 조절할 수 있는 positive regulator로서 작용하고, tetracycline-VP16 system에서는 tetracycline이나 유사물질들이 negative regulator로서 이용할 수 있다. 이러한 binary system은 transgenic animal에서 이식유전자 발현의 장소와 시기 또한 양을 효과적으로 조절하는데 적용할 수 있는 것으로 나타났다. 따라서 기존의 binary system과 함께 새로운 regulatory system의 장점을 이용하여 보다 완벽한 이식유전자의 인위적인 조절 system을 이룩함으로서 transgenic animal technology의 실용화를 앞당길 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.6
• /
• pp.743-749
• /
• 2004

The gene encoding human serum albumin (HSA) was cloned from human liver cDNA library by PCR. The HSA cDNA in size of 2,176 bp, including 1,830 bp of open reading frame, was cloned into the plasmid carried with the 5'flanking sequence of goat $\beta$-casein gene (-4,044 to +2,025 bp) to get a tissue specific expression vector in mammary gland named pGB562/HSA (12.5 kb). A 9.6 kb DNA fragment in which the sequence is in order of goat $\beta$-casein gene regulatory sequence, HSA cDNA and SV40 polyadenylation signals was isolated from the pGB562/HSA by SacI and DraIII cutting, and used to microinject into the pronuclei of mouse fertilized eggs to produce transgenic mice. Three transgenic mice (2 female and 1 male) were identified by PCR and dot Southern blot analysis. The copy numbers of integrated transgene were more than 10 copies in line #21 and #26 as well as over 50 copies in line #31 of transgenic mice. HSA protein collected from the milk of lactating transgenic mice was confirmed by immuno-detection of Western and slot blot. The concentrations of HSA in the milk were from 0.05 to 0.4 mg/ml. An obvious antigen and antibody conjugate could be observed in immunohistochemical stain of mammary gland tissue from lactating day 11 of HSA transgenic mice. The transmission of transgene and its expression was recognized according to the results of RT-PCR and sequences analyses of their progeny.

• Proceedings of the Korean Society of Developmental Biology Conference
• /
• 2003.10a
• /
• pp.106-106
• /
• 2003

Human papillomavirus type 16(HPV16) has been known to the major factor for the development of uterine cervical carcinomas. We have extended these studies to investigate the in vivo activities of HPV-16 E6/E7 when expressed in squamous epithelia of transgenic mice. Grossly, hK14HPV16E6/E7 transgenic mice had multiple phenotypes, including wrinkled skin that was apparent prior to the appearance of hair on neonates, thickened ears, and loss of hair in adults. In the transgenic mice, the wrinkled skin phenotype on the body and legs died at the age of 3-4 weeks. Histological analysis of demonstrated that E6/E7 causes epidermal hyperplasia in multiple transgenic lineages with high penetrance. This epithelial hyperplasia was characterized by an expansion of the proliferating compartment and an expansion of the keratinocyte and was associated with hyperkeratosis. These transgenic mice expressed E6/E7 transgene mainly in skin, heart, pancreas and kidney. Hyperplasia was found at the skin. The enzyme activities of GR, GPx and CuZnSOD were measured from the transgene cause keratinocyte at the skin. The specific enzyme activities were significantly higher in transgenic mice skin compared to the normal mice skin. Thus these transgenic mice may be useful for the develpment of antioxidant enzymes or other therapies for HPV-associated hyperkeratosis.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.4
• /
• pp.461-465
• /
• 2007

Porcine Endogenous Retroviruses (PERVs) are a major concern in relation to xenotransplantation. Previous research indicated that PERVs are present at about 50 copies in the pig genome and their chromosomal insertion sites are different among pig breeds. We examined nine Korean native pigs and seven Asian Wild Boars for the presence of a PERV-A at SSC 1q2.4 and a PERV-B at SSC 7p1.1-2 previously reported in a Large White pig. The PERV-B at locus 7p1.1-2 displayed insertional variability in Korean native pigs and Asian Wild Boars. Using the primers for the PERV-A at 1q2.4 from Large White pig, we only can amplify an unclassified 798 bp sequence, which showed insertional variability only in Korean native pigs. This study indicates that there are differences within and between Asian and European pigs in PERV insertions and suggests that selection could generate PERV-free lines of pigs more suitable for xenotransplantation.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.5
• /
• pp.657-662
• /
• 2008

To develop transgenic orchardgrass (Dactylis glomerata L.) resistant to high temperature, the recombinant DgHSP17.2 gene was introduced into orchardgrass plants using the Agrobacterium-mediated transformation method and expressed constitutively under the control of the CaMV 35S promoter. The results of genomic DNA PCR and Southern analysis showed a DNA band and hybridization signal on agarose gel and X-ray film in transgenic orchardgrass plants harboring the recombinant DgHSP17.2 gene, but a DNA band and hybridization signal were not observed in the wild type and empty vector control plants. The same result was also obtained in RT-PCR and Southern blot analysis, and these transgenic orchardgrass plants did not show any morphological aberration both in the culture bottle and soil mixture. When leaf discs cut from transgenic orchardgrass plants with recombinant DgHsp17.2 gene were exposed to lethal temperature (heat treatment at $60^{\circ}C$ for 50 min), 60-80% of the leaf discs showed only damage symptoms, but non-transgenic leaf discs showed a lethal condition. These results indicate that the DgHsp17.2 gene may act as a protector from heat stress in plants.

• Korean Journal of Agricultural Science
• /
• v.43 no.4
• /
• pp.575-580
• /
• 2016

This study was performed to determine whether supplementation of tauroursodeoxycholic acid (TUDCA), an endoplasmic reticulum (ER) stress inhibitor, during vitrified cryopreservation enhances the development of frozen mouse embryos. Mouse 8-cell stage embryos were collected and exposed to a cryoprotectant solution containing TUDCA or TM (tunicamycin, an ER stress inhibitor) at room temperature and stored in liquid nitrogen following vitrification. The final concentration of TUDCA or TM was $50{\mu}M$. The survival and development rates of mouse 8-cell stage embryos exposed to TUDCA- or TM-containing solutions at room temperature or stored in liquid nitrogen following vitrification were measured. There were no significant differences in survival rate and blastocyst formation rate among control, TUDCA, and TM groups after embryos were exposed to vitrification solutions at RT. When mouse 8-cell stage embryos were treated with TUDCA or TM and then stored in liquid nitrogen, the survival rates of control and TUDCA groups were significantly higher than for the TM group. Blastocyst formation rate of the TUDCA group following in vitro culture was significantly higher than that in control or TM groups. The TM group showed a lower (p < 0.05) blastocyst formation rate than the other two groups. Our results indicate that TUDCA supplementation during cryopreservation of mouse embryos could enhance their development capacity.

• Proceedings of the KSAR Conference
• /
• 2001.03a
• /
• pp.47-47
• /
• 2001

The neuropeptide vasopressin (VP) is a nine- amino acid hormone synthesized as preprohormone in the cell bodies of hypothalamic magnocellular neurons. The tumor in magnocellular neurons of the hypothalamus is associated with disfunctions of the cell bodies, leading to the diabetes insipidus. In order to study with the diabetes insipidus caused by a defect in VP synthesis and its secretion, we have produced the transgenic mice regulated by vasopressin promoter inserted to SV40 T antigen coding sequence (pVPSV.IGR2.1). One transgenic line expressing high levels of SV40 T antigen was propagated. The founder and all transgene positive adult animals have appeared with shorten mortality or apparent phenotypic abnormalities, including immune complex disease, and eventually die between 4 and 8 months of age. The mRNA and protein of SV40T antigen transgene were detected in brain of fetus as well as in brain, spleen, lung and lymph node in moribund at the age of 20 weeks. Histological analysis of transgenic mice showed that tumor developed in brain similar to primitive neuroectodermal tumors (PNET) in man. We also detected lymphomas in spleen and lymph node, and consequent tumor formation in various tissues of the transgenic mice. In pVPSV.IGR2.1, 21% mice showed brain tumor (PNET) at 5 weeks and 100% mice showed brain tumor after 15 weeks. In addition, Expression of apoptosis related genes (Bcl-28 & Bax) was increased over their age in mice with PNET as compared to control mice. Apoptosis related gene expression might be deregulated in mice with brain tumor. However, transgenic mice were not developed with the diabetes insipidus. These mice represent the first disease model to exhibit primitive neuroectodermal tumor in brain, as well as a unique model system for exploring the cellular pathogenesis of lymphomas.

• Reproductive and Developmental Biology
• /
• v.33 no.2
• /
• pp.113-117
• /
• 2009

Animals produced by somatic cell nuclear transfer (SCNT) using genetically modified cells are almost always transgenic, implying that this method is more efficient than the traditional pronuclear microinjection method. Most somatic cells for SCNT in animals are fetus-derived primary cells and successful gene integration in somatic cells will depend on transfection condition. The objective of this study is to evaluate the efficiency of electroporation (Microporator) and liposome reagents (F-6, F-HD, W-EX, W-Q, W-M) for tissue-type plasminogen activator (tPA) gene transfection and to estimate the overall efficiency of transfection of Korean native pig fetal fibroblast cells (KNPFF). Electroporation showed significantly higher transfection efficiency than liposome reagents with regard to the transfection of in vitro cultures in the early stages of development (41.7% with Microporator vs. 18.3% with F-6, 20.0% with F-HD 18.5% with W-EX, 5.0% with W-M and 6.3% W-Q,). Colonies identified as tPA-positives were treated once more with G418 for 10 to 14 days and growing colonies were selected again. When the cells of newly selected colonies were subjected to single-cell PCR, reselection of colonies following second round of G418 selection increased the rate of transgene integration per each colony. These results suggest that transfection with electroporation is the most efficient and the second rounds of G418 selection may be an effective method for transfection of porcine fetal fibroblast cells.

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2003.10a
• /
• pp.121-121
• /
• 2003