SooAm Biotech Research Foundation

Seoul, South Korea

SooAm Biotech Research Foundation

Seoul, South Korea
Time filter
Source Type

PubMed | BGI Shenzhen, Chonnam National University, Chungbuk National University and Sooam Biotech Research Foundation
Type: | Journal: Scientific reports | Year: 2016

Somatic cell nuclear transfer (SCNT) provides an excellent model for studying epigenomic reprogramming during mammalian development. We mapped the whole genome and whole methylome for potential anomalies of mutations or epimutations in SCNT-generated dogs with XY chromosomal sex but complete gonadal dysgenesis, which is classified as 78, XY disorder of sex development (DSD). Whole genome sequencing revealed no potential genomic variations that could explain the pathogenesis of DSD. However, extensive but stochastic anomalies of genome-wide DNA methylation were discovered in these SCNT DSD dogs. Persistent abnormal hypermethylation of the SRY gene was observed together with its down-regulated mRNA and protein expression. Failure of SRY expression due to hypermethylation was further correlated with silencing of a serial of testis determining genes, including SOX9, SF1, SOX8, AMH and DMRT1 in an early embryonic development stage at E34 in the XY(DSD) gonad, and high activation of the female specific genes, including FOXL2, RSPO1, CYP19A1, WNT4, ER and ER, after one postnatal year in the ovotestis. Our results demonstrate that incomplete demethylation on the SRY gene is the driving cause of XY(DSD) in these XY DSD dogs, indicating a central role of epigenetic regulation in sex determination.

PubMed | University of Veterinary and Animal Sciences, Seoul National University, Chungbuk National University, Sooam Biotech Research Foundation and Gyeonggi Do
Type: Journal Article | Journal: PloS one | Year: 2014

To determine whether exogenous amino acids affect gene transcription patterns in parthenogenetic porcine embryos, we investigated the effects of amino acid mixtures in culture medium. Parthenogenetic embryos were cultured in PZM3 medium under four experimental conditions: 1) control (no amino acids except L-glutamine and taurine); 2) nonessential amino acids (NEAA); 3) essential amino acids (EAA); and 4) NEAA and EAA. The rate of development of embryos to the four-cell stage was not affected by treatment. However, fewer (P<0.05) embryos cultured with EAA (12.8%) reached the blastocyst stage as compared with the control group (25.6%) and NEAA group (30.3%). Based on these findings, we identified genes with altered expression in parthenogenetic embryos exposed to medium with or without EAAs. The results indicated that EAA influenced gene expression patterns, particularly those of imprinted genes (e.g., H19, IGF2R, PEG1, XIST). However, NEAAs did not affect impaired imprinted gene expressions induced by EAA. The results also showed that mechanistic target of rapamycin (MTOR) mRNA expression was significantly increased by EAA alone as compared with control cultures, and that the combined treatment with NEAA and EAA did not differ significantly from those of control cultures. Our results revealed that gene transcription levels in porcine embryos changed differentially depending on the presence of EAA or NEAA. However, the changes in the H19 mRNA observed in the parthenogenetic blastocysts expression level was not related to the DNA methylation status in the IGF2/H19 domain. The addition of exogenous amino acid mixtures affected not only early embryonic development, but also gene transcription levels, particularly those of imprinted genes. However, this study did not reveal how amino acids affect expression of imprinted genes under the culture conditions used. Further studies are thus required to fully evaluate how amino acids affect transcriptional regulation in porcine embryos.

Park C.-H.,Sooam Biotech Research Foundation | Jeong Y.H.,Sooam Biotech Research Foundation | Jeong Y.-I.,Sooam Biotech Research Foundation | Lee S.-Y.,Sooam Biotech Research Foundation | And 8 more authors.
PLoS ONE | Year: 2012

To determine the presence of sexual dimorphic transcription and how in vitro culture environments influence X-linked gene transcription patterns in preimplantation embryos, we analyzed mRNA expression levels in in vivo-derived, in vitro-fertilized (IVF), and cloned porcine blastocysts. Our results clearly show that sex-biased expression occurred between female and male in vivo blastocysts in X-linked genes. The expression levels of XIST, G6PD, HPRT1, PGK1, and BEX1 were significantly higher in female than in male blastocysts, but ZXDA displayed higher levels in male than in female blastocysts. Although we found aberrant expression patterns for several genes in IVF and cloned blastocysts, similar sex-biased expression patterns (on average) were observed between the sexes. The transcript levels of BEX1 and XIST were upregulated and PGK1 was downregulated in both IVF and cloned blastocysts compared with in vivo counterparts. Moreover, a remarkable degree of expression heterogeneity was observed among individual cloned embryos (the level of heterogeneity was similar in both sexes) but only a small proportion of female IVF embryos exhibited variability, indicating that this phenomenon may be primarily caused by faulty reprogramming by the somatic cell nuclear transfer (SCNT) process rather than in vitro conditions. Aberrant expression patterns in cloned embryos of both sexes were not ameliorated by treatment with Scriptaid as a potent HDACi, although the blastocyst rate increased remarkably after this treatment. Taken together, these results indicate that female and male porcine blastocysts produced in vivo and in vitro transcriptional sexual dimorphisms in the selected X-linked genes and compensation of X-linked gene dosage may not occur at the blastocyst stage. Moreover, altered X-linked gene expression frequently occurred in porcine IVF and cloned embryos, indicating that X-linked gene regulation is susceptible to in vitro culture and the SCNT process, which may eventually lead to problems with embryonic or placental defects. © 2012 Park et al.

Park C.-H.,Sooam Biotech Research Foundation | Park C.-H.,South Korean National Institute of Animal Science | Park C.-H.,Seoul National University | Uh K.-J.,Sooam Biotech Research Foundation | And 7 more authors.
PLoS ONE | Year: 2011

In the present study quantitative real-time PCR was used to determine the expression status of eight imprinted genes (GRB10, H19, IGF2R, XIST, IGF2, NNAT, PEG1 and PEG10) during preimplantation development, in normal fertilized and uniparental porcine embryos. The results demonstrated that, in all observed embryo samples, a non imprinted gene expression pattern up to the 16-cell stage of development was common for most genes. This was true for all classes of embryo, regardless of parental-origins and the direction of imprint. However, several differentially expressed genes (H19, IGF2, XIST and PEG10) were detected amongst the classes at the blastocyst stage of development. Most interestingly and despite the fact that maternally and paternally expressed genes should not be expressed in androgenones and parthenogenones, respectively, both uniparental embryos expressed these genes when tested for in this study. In order to account for this phenomenon, we compared the expression patterns of eight imprinted genes along with the methylation status of the IGF2/H19 DMR3 in haploid and diploid parthenogenetic embryos. Our findings revealed that IGF2, NNAT and PEG10 were silenced in haploid but not diploid parthenogenetic blastocysts and differential methylation of the IGF2/H19 DMR3 was consistently observed between haploid and diploid parthenogenetic blastocysts. These results appear to suggest that there exists a process to adjust the expression status of imprinted genes in diploid parthenogenetic embryos and that this phenomenon may be associated with altered methylation at an imprinting control region. In addition we believe that imprinted expression occurs in at least four genes, namely H19, IGF2, XIST and PEG10 in porcine blastocyst stage embryos. © 2011 Park et al.

PubMed | Harvard University, Seoul National University of Science and Technology, Sooam Biotech Research Foundation and Seoul National University
Type: Journal Article | Journal: Zygote (Cambridge, England) | Year: 2016

The development of embryonic stem cells (ESCs) from large animal species has become an important model for therapeutic cloning using ESCs derived by somatic cell nuclear transfer (SCNT). However, poor embryo quality and blastocyst formation have been major limitations for derivation of cloned ESCs (ntESCs). In this study, we have tried to overcome these problems by treating these cells with histone deacetylase inhibitors (HDACi) and aggregating porcine embryos. First, cloned embryos were treated with Scriptaid to confirm the effect of HDACi on cloned embryo quality. The Scriptaid-treated blastocysts showed significantly higher total cell numbers (29.50 2.10) than non-treated blastocysts (22.29 1.50, P < 0.05). Next, cloned embryo quality and blastocyst formation were analyzed in aggregates. Three zona-free, reconstructed, four-cell-stage SCNT embryos were injected into the empty zona of hatched parthenogenetic (PA) blastocysts. Blastocyst formation and total cell number of cloned blastocysts increased significantly for all aggregates (76.4% and 83.18 8.33) compared with non-aggregates (25.5% and 27.11 1.67, P < 0.05). Finally, aggregated blastocysts were cultured on a feeder layer to examine the efficiency of porcine ES-like cell derivation. Aggregated blastocysts showed a higher primary colony formation rate than non-aggregated cloned blastocysts (17.6 12.3% vs. 2.2 1.35%, respectively, P < 0.05). In addition, derived ES-like cells showed typical characters of ESCs. In conclusion, the aggregation of porcine SCNT embryos at the four-cell stage could be a useful technique for improving the development rate and quality of porcine-cloned blastocysts and the derivation efficiency of porcine ntESCs.

Jung E.-M.,Chungbuk National University | Kim Y.-K.,SooAm Biotech Research Foundation | Lee G.-S.,Kangwon National University | Hyun S.-H.,Chungbuk National University | And 2 more authors.
Molecular Medicine Reports | Year: 2012

Diabetes mellitus is a metabolic disease caused by impaired insulin secretion from the pancreatic β cells and increased insulin resistance in peripheral tissues. Recently, the overexpression of inducible cyclic AMP (cAMP) early repressor (ICER) Iγ in rodent pancreatic β cells was found to induce insulin deficiency and glucagon overproduction similar to that found in human diabetes mellitus. ICER Iγ with only a DNA binding domain interrupts the transcriptional regulation of the cAMP responsive element-binding protein (CREB) target genes. Based on this information, we hypothesized that the overexpression of ICER Iγ, the most powerful competitor to CREB, could be useful for generating a pig model of diabetes. First, we evaluated the promoter activities of the human insulin gene for the β cell-specific overexpression of ICER Iγ in the pig pancreas. The maximum promoter activity region [-1,431 nucleotides (nt) to +1 nt, +1 = the transcriptional start site] of the insulin gene presented an activity level 3-fold higher than a promoterless construct. Second, ICER Iγ overexpression controlled by this promoter region significantly blocked the glucose-mediated insulin transcription, such as that regulated by the viral promoter in the pancreatic β cell line, MIN6. This suggests that the human insulin promoter may facilitate the overexpression of ICER Iγ in porcine pancreatic β cells. In addition, the overexpression of ICER Iγ in porcine β cells may induce human-like type 1 diabetes mellitus in pigs. In the present study, we generated transgenic fibroblasts containing ICER Iγ cDNA controlled by the human insulin promoter, as well as two screening markers, the green fluorescence protein and the neomycin resistance gene. These fibroblasts may provide a source for somatic cell nuclear transfer to generate a pig model that mimics human diabetes mellitus.

Kim Y.-K.,SooAm Biotech Research Foundation | Lee G.-S.,Kangwon National University | Jung E.-M.,Chungbuk National University | Hyun S.-H.,Chungbuk National University | And 2 more authors.
Molecular Medicine Reports | Year: 2012

Type 2 diabetes mellitus (T2DM) is one of the most common complex metabolic disorders in humans, and is characterized by hyperglycemia and metabolic alterations. In T2DM, fasting hyperglycemia is attributed to excessive hepatic glucose production, and increased gluconeogenesis has been ascribed to increased transcriptional expression of phosphoenolpyruvate carboxykinase (PEPCK). In this study, we analyzed porcine PEPCK promoter activities to generate liver-specific expression vectors. We generated miniature pig fibroblasts overexpressing PEPCK via transgenes to provide an animal model of human T2DM. Various regions of the promoter showed high levels of activity in the presence of glucocorticoids, a PEPCK gene inducer, in liver cells compared to a positive control promoter. The selected promoter region for a liver-specific expression system was adopted based on the current targeting vector containing two selection markers, green fluorescence protein and a neomycin-resistance gene. The linearized vector was introduced into pig fibroblasts which facilitated liver-specific PEPCK overexpression and screening according to the two selection markers. In the present study, we used a liposome-mediated transfection protocol rather than a virus-mediated gene delivery system, since the virus may cause side effects. Following transfection, 46 colonies out of 33 transfection trials had positively integrated the overexpression vector, indicating that a relatively high transfection efficiency rate was obtained by the liposomal-mediated system. Thus, we recommend the optimal liver-specific expression system for safe and effective transfection of pig cells. We plan to use these cells for somatic cell nuclear transfer to produce piglets that overexpress liver-specific PEPCK as an animal model for human T2DM.

Jeong Y.-H.,Sooam Biotech Research Foundation | Park C.-H.,Sooam Biotech Research Foundation | Jang G.-H.,Sooam Biotech Research Foundation | Jeong Y.-I.,Sooam Biotech Research Foundation | And 8 more authors.
PLoS ONE | Year: 2013

The present study was conducted to generate transgenic pigs coexpressing human CD55, CD59, and H-transferase (HT) using an IRES-mediated polycistronic vector. The study focused on hyperacute rejection (HAR) when considering clinical xenotransplantation as an alternative source for human organ transplants. In total, 35 transgenic cloned piglets were produced by somatic cell nuclear transfer (SCNT) and were confirmed for genomic integration of the transgenes from umbilical cord samples by PCR analysis. Eighteen swine umbilical vein endothelial cells (SUVEC) were isolated from umbilical cord veins freshly obtained from the piglets. We observed a higher expression of transgenes in the transgenic SUVEC (Tg SUVEC) compared with the human umbilical vein endothelial cells (HUVEC). Among these genes, HT and hCD59 were expressed at a higher level in the tested Tg organs compared with non-Tg control organs, but there was no difference in hCD55 expression between them. The transgenes in various organs of the Tg clones revealed organ-specific and spatial expression patterns. Using from 0 to 50% human serum solutions, we performed human complement-mediated cytolysis assays. The results showed that, overall, the Tg SUVEC tested had greater survival rates than did the non-Tg SUVEC, and the Tg SUVEC with higher HT expression levels tended to have more down-regulated α-Gal epitope expression, resulting in greater protection against cytotoxicity. By contrast, several Tg SUVEC with low CD55 expression exhibited a decreased resistance response to cytolysis. These results indicated that the levels of HT expression were inversely correlated with the levels of α-Gal epitope expression and that the combined expression of hCD55, hCD59, and HT proteins in SUVECs markedly enhances a protective response to human serum-mediated cytolysis. Taken together, these results suggest that combining a polycistronic vector system with SCNT methods provides a fast and efficient alternative for the generation of transgenic large animals with multiple genetic modifications. © 2013 Jeong et al.

PubMed | Chungbuk National University and Sooam Biotech Research Foundation
Type: Journal Article | Journal: Molecular medicine reports | Year: 2015

Interferon (IFN-) is a cytokine, produced predominantly in immune cells in response to pathogens, which interferes with viral replication in host cells. Another cytokine hormone, erythropoietin (EPO), is synthesized in interstitial fibroblasts of the kidney and acts as a stimulator for the production of red blood cells. Importantly, the two cytokines have been used in the treatment of certain hematological malignancies, including renal anemia. In the production of recombinant proteins, a transgenic expression system in bovine species is an efficient strategy for pharmaceutical production. In the present study, recombinant constructs capable of producing recombinant human IFN- and EPO proteins were established and were generated containing the mammary gland-specific S1-casein promoter region (between -175 and + 796 nt), as this promoter was revealed to have the highest level of activity in a previous promoter study. In order to minimize developmental toxicity by constitutive exogenous expression, a doxycycline (dox)-inducible system was introduced to the IFN-/EPO-expressing constructs. Therefore, a unitary tetracycline (tet)-on the IFN-/EPO vector was established, which combined a tet-on activator cassette controlled by the S1-casein promoter, with a responder cassette encoding the IFN-/EPO gene, controlled by the tetracycline response element (TRE) promoter. In these systems, the tet-controlled transactivator is affected by mammary gland-specific S1-casein promoter, and binding of the transcriptional activator to the TRE results in transcription of the downstream IFN-/EPO genes in the presence of dox. To assess this, the unitary tet-on IFN-/EPO vector was introduced into a bovine mammary gland cell line (MAC-T), and the cells were then treated with 0.1-1 g/ml dox. A marked increase was observed in the expression levels of IFN-/EPO. In addition, bovine transgenic fibroblasts containing a mammary gland-specific and dox-inducible IFN-/EPO construct were generated. These transgenic fibroblasts may provide a source for somatic cell nuclear transfer for the generation of transgenic cattle producing recombinant human IFN-/EPO protein during lactation.

PubMed | Chungbuk National University and Sooam Biotech Research Foundation
Type: Journal Article | Journal: Theriogenology | Year: 2016

Dog cloning offers a substantial potential because of the advancements in assisted reproductive technology and development of the human disease model in line with the transgenic technique. However, little is known about the development of the canine cloned embryo during the preimplantation period. The aim of this study was to investigate the most efficient method and time for collecting cloned canine preimplantation embryos and to ascertain the developmental timeline of cloned canine embryos. Two hundred cloned embryos were created and transferred into 11 surrogates. The preimplantation stage cloned embryos were then collected on Days 7, 8, and 9 using an ovariohysterectomy or the Foley balloon catheter method. The recovery rate of reconstructed embryos was 63.6% and 60.6% for the ovariohysterectomy and Foley balloon catheter methods, respectively. Although significant differences were observed in the early developmental stages (one-cell and 16-cell stages), no significant difference was observed in the blastocyst stage. Significantly higher blastocyst rate was observed when the embryos were collected on Day 8 (11.4%) than on Day 7 (0.0%; P<0.05). At the proximal uterine horn on Day 7, no embryos at any stage were found, whereas on Days 8 and 9, blastocysts were found. We have observed a 63% initial pregnancy rate at 25 to 30days after embryo transfer and a 50% full-term pregnancy rate, whereas 6.3% of the puppies were born, and 5.5% were born live among the total transferred embryos. Our results suggest that cloned embryos can develop to blastocysts by Day 8, and full-term pregnancy can be achieved after embryo transfer in canine.

Loading SooAm Biotech Research Foundation collaborators
Loading SooAm Biotech Research Foundation collaborators