Traf4 (Tumor necrosis factor Receptor Associated Factor 4) is a member of the tumor necrosis factor receptor (TNFR) - associated factors (TRAFs) family. TRAF4 is overexpressed in tumor cells such as breast cancer and associated with cytoskeleton and membrane fraction. Interestingly, TRAF4 was localized with tight junctions (TJs) proteins including OCLN and TJP1 in mammary epithelial cells. However, the expression patterns and biological function of Traf4 were not examined in preimplantation mouse embryos although Traf4-deficient mouse showed embryonic lethality or various dramatic malformation. In this study, we examined the temporal and spatial expression patterns of mouse Traf4 during preimplantation development by qRT-PCR and immunostaining, and its biological function by using siRNA injection. We found upregulation of Traf4 from the 8-cell stage onwards and apical region of cell – cell contact sites at morula and blastocyst embryos. Moreover, Traf4 knockdown led to defective TJs without alteration of genes associated with TJ assembly but elevated p21 expression at the KD morula. Taken together, Traf4 is required for TJs assembly and cell proliferation during morula to blastocyst transition.
The aim of this study was to investigate the role of Src homology 2-containing
phosphotyrosine phosphatase SHP2 in intricate signaling network invoked by oocyte to
achieve cytoplasmic maturation and also blastocyst development. Activation of SHP2
regulates multicellular differentiation, proliferation and survival through numerous signal
pathways. The most prominent pathway is RAS/PI3K and p-AKT signaling cascade, as
a result mitogenic effect become enhanced. Oocytes were cultured in cisplatin an
anticancer drug, but selective activator of SHP2 and our grouping were SOF medium alone,
SOF + EGF, SOF + CISPLATIN 0.3 μM, and SOF + EGF + CISPLATIN 0.3 μM. We
evaluated that EGF neutralizes the apoptotic effect of cisplatin as well as maintain the
high expression of SHP2, as a result blastocyst development become boosted up. We
also found that inhibition of SHP2 with its specific inhibitor PHPS1 5 μM decreases the
blastocyst development and neutralizes growth factors effect. The developmental ability
and quality of bovine embryos were determined by assessing their cell number, gene
expression, immunofluorescence, and immunoblot. The differences in embryo
development between experimental groups were analyzed by one-way ANOVA. Our
results show that SHP2 have significant effect on MAP kinase pathways which expand
the cumulus cells during oocyte maturation and blastocyst development as compare to
inhibition of SHP2 with PHPS1. SHP2 not only transduce the signaling of epidermal growth
factor but it also has a role in signal transduction of FGF and IGF. The expression of
ERK, PI3K/p-AKT and mTOR was increased with EGF, but with the treatment of SHP2
inhibitor the expression of these genes become drop done. So we can conclude from these
results that SHP2 is important for oocyte maturation as well as for blastocyst
development.
This study aimed to produce high-quality blastocysts and establish appropriate microinjection conditions for the introduction of target gene. First, we identified embryo development to the blastocyst stage after microinjection using the CRISPR/Cas9 system on the Cas9 protein or mRNA. As a result, we confirmed that blastocyst development in the Cas9 mRNA injected group significantly increased when compared to the Cas9 protein injected group (p<0.05). However, the blastocyst gene targeting rate increased in the Cas9 protein injected group when compared to the Cas9 mRNA injected group (p<0.05). Next, we treated the injection medium with 10 μg/ml of cytochalasin B (CB), and the microinjected embryos were cultured in CR1-aa medium supplemented with 0.1 μM of melatonin (Mela). Consequently, the blastocyst formation rate significantly increased in the CB treated group (p<0.05). After microinjecting embryos with the CB treated injection medium, we investigated blastocyst formation and quality via Mela treatment. Consequently, the Mela treated group demonstrated significantly increased blastocyst formation rates when compared to the non-treated group (p<0.05). Furthermore, immunofluorescence assay using RAD51 (DNA repair detection protein) and H2AX139ph (DNA damage detection protein) showed an increase in RAD51 positive cells in Mela treated embryos. Therefore, we verified the improvement in knock-in efficiency in microinjected bovine embryos using Cas9 protein. These results also demonstrated that the positive effect of the CB and Mela treatments improved the embryonic developmental competence and blastocyst qualities in genetically-edited bovine embryos.
Establishment of the Adherens junction (AJ) and Tight junction (TJ) are important steps in terms of morphological formation during preimplantation develoment. Particularly, TJ complex is crucial for cavitation in blastocyst. So far, many TJ protein/genes are revealed. However, the biological function and regulation of TJ were not elucidated during post implantation. We depleted several TJ and TJ associated genes using RNA interference, and examined preimplantation development with TJ. We tested functionality of paracellular sealing to determine integrity of TJ formation and examined TE differentiation indirectly using outgrowth assay in vitro. We observed defect of paracellular permeability in the TJ related genes knockdown(KD) blastocyst and abnormal outgrowth. Particularly, trophoblast cells were not stretched out in the KD groups. Finally, we did embryo transfer using the TJ genes KD and control blastocysts into surrogate mothers. We found lower of the implantation rates/ maintenance of pregnancy in the TJ KD groups (less than 40%) than in the controls (about 80%). In conclusion, TJ integrity is can be used as a selective marker for developmentally competent embryos and successful pregnancy.
Fatty acid synthesis (FASN) is an enzyme responsible for the de novo synthesis of long-chain fatty acids. During oncogenesis, FASN plays a role in growth and survival rather than acting within the energy storage pathways. Here, the function of FASN during early embryonic development was studied using its specific inhibitor C75. We found that the presence of the inhibitor reduced blastocyst hatching. FASN inhibition decreased Cpt1 expression, leading to a reduction in mitochondrial copy numbers and ATP content. This inhibition of FASN results in the down-regulation of the AKT pathway, thereby triggering apoptosis through the activation of the p53 pathway. Activation of the apoptotic pathways also leads to increased accumulation reactive oxygen species and autophagy. In addition, the FASN inhibitor can impair cell proliferation, a parameter of blastocyst quality for outgrowth. The level of OCT4, an important factor in embryonic development, decreased after treatment with the FASN inhibitor. These results show that FASN exerts an effect on the early embryonic development by regulation of both fatty acid oxidation and the AKT pathway in pigs.
These studies were conducted to establish the practical Hanwoo (Korean native cattle) improvement system through the combining of embryo transfer technology and confirming individual Hanwoo oocyte culture system and to investigate that correlation of Hanwoo carcass classification (intramuscular marbling) and oocyte donor for blastocyst production in vitro. In case of Hanwoo, the carcass meat quality grades were divided to grade 1⁺⁺, 1⁺, 1, 2, and 3 depends on fat distribution of longest muscle cross-sectional surface. As results, the numbers of follicular oocytes collected from individual fundamentally-registered Hanwoo yielded 1⁺⁺, 1⁺, 1, 2 and 3 meat quality were 9.5, 9.4, 8.5, 8.8 and 8.8 per ovary, respectively. The numbers of retrieval oocyte from follicles were significantly higher in the cattle yield 1⁺⁺, 1⁺ meat quality than in the cattle yield 1, 2 and 3 meat quality (p<0.05). The rates of blastocyst formation were 18.2, 21.3, 29.4, 30.9, and 31.5% in the cattle yield 1⁺⁺, 1⁺, 1, 2 and 3 meat quality of after in vitro maturation, respectively. It was significantly lower in the cattle yield 1⁺⁺ and 1⁺ meat quality than in the cattle yield 1, 2 and 3 meat quality (p<0.05). In order to evaluate embryos quality, TUNNEL assay was conducted for each meat quality grade using blastocyst stage embryo on day 8. The results showed that apoptosis cell number was higher tendency in the cattle yield 1⁺⁺and 1⁺ meat quality (81 and 79, respectively) than in the cattle yield 1, 2 and 3 meat quality (51, 48 and 50, respectively) but there was no statistical significance in each group. After embryo transfer, the conception rate of recipient was 53.5 (23 out of 43), 52.1 (38 out of 73) and 58.0% (58 out of 100) in the meat quality of 1, 1+ and 1++, respectively. These results showed that the conception rate was significantly higher in the cattle yield 1 meat quality than in the cattle yield 1⁺⁺, 1⁺ , 2, and 3 meat quality (p<0.05). In summary, these results indicate that the application of confirming Hanwoo individual oocyte culture system and embryo transfer technology can make good use of the genetic resources conservation and improvement of Hanwoo. Relevance of the meat quality grade and reproductive ability of carcasses of Hanwoo will be considered to be one of the effective means for the associated research with obesity and reproduction.
Superovulation, or ovarian stimulation is a commonly used ART for treatment of human infertility/subfertility. Recent studies suggest that superovulation unaffects methylated imprints acquisition in mouse oocytes during oogenesis, whereas disrupts DNA methylation maintenance in embryos during preimplantation development. However, the mechanisms of defects in methylation maintanence caused by superovulation remain largely unclear. We hypothesized that superovulation may disrupt the expression of DNA methyltransferases (Dnmts), the enzymes which catalyze DNA methylation acquisition and maintenance. The mice were subjected to superovulate with low (6 IU) and high (10 IU) dosage hormone. We examined the global DNA methylation levels in zygotes and DNA methylation of repeated sequences (IAP and Line 1) in blastocyst stage embryos. In addition, we investigated the expression of Dnmts (Dnmt3a, Dnmt3b, Dnmt3l and Dnmt1o) in ovulated oocytes and zygotes. Through staining with antibody 5mC and Di-H3K9 coupled with confocal microscopy, we found that global methylation profiles in zygotes derived from females after low or high dosage hormone treatment were not affected when compared to control counterpart. Moreover, methylation at IAP in blastocysts also was unaffected by superovulation, irrespective of hormone dosage. In contrast, methylation level at Line 1 decreased when the females were administered by high dosage hormone. Furthermore, expression of de novo DNA methyltransferase Dnmt3a, Dnmt3b, Dnmt3L, as well as maintenance Dnmt1o in MII oocytes and zygotes was not disrupted by superovulation. Given superovulation adversely affected methylation maintenance in blastocysts during preimplantation development but with normal expression of Dnmts in oocytes and zygotes, it is indicated that defects of embryonic methylation didn’t originate from abnormal expression of Dnmts.
Poly(ADP-ribosyl)ation is post-translational modification of cellular proteins related to cell survival, cell death, cellular proliferation and epigenetic events. It has recently been shown to be important for pre-implantation development of mouse embryos. However, its function during early embryonic development of pig is not clear. This study investigated the importance of poly(ADP-ribosyl)ation during in vitro development of pig embryos produced by in vitro fertilization(IVF) or parthenogenetic activation (PA). Results showed that, chemical inhibition of PARP by 3-aminobenzamide (3-AB) did not influence the in vitro development of pig embryos up to morula stage (20±3.1 vs. 28.1±1.2%; p>0.05) but significanlty reduced the rate of blastocyst formation (5.2±2.1 vs. 20±3.1%; p<0.05) when compared to non-treated controls. Furthermore, culture of morula stage embryos in the pressence of 3-AB for 24h significantly reduced the rate of blastocyst formation (19.6± 4.6 vs. 41.4±5.3%; p<0.05) and expansion (4.7±3.0 vs. 28.1±6.1; p<0.05). The proportion of large-sized blastocyst (>200 μm) having higher blastocoel volume (15.3×106 μm3) was significantly reduced (p<0.05) in treatment group (32.2±7.8%) compared to non-treated control group (65.7±9.0%). TUNEL assay revealed that poly(ADP-ribosyl)ation-inhibited blastocyst had significantly increased indices of apoptosis than those of non-treated controls (10.88±0.02 vs. 2.71±0.01; p<0.05). These data suggest that Poly(ADP-ribosyl)ation may be important for blastocyst formation in pig embryo.
Somatic cell nuclear transfer (SCNT) and induced pluripotent stem cell (iPS) experiments have generally demonstrated that a differentiated cell directly converts into a undifferentiated or pluripotent state. In SCNT experiment, nuclear reprogramming is induced by exposure of introduced donor cell nuclei to the recipient cytoplasm of matured oocytes. Although nuclear reprogramming of cells by the ex-ovo methods is not always consistent or efficient, it has been suggested that a combination of nuclear reprogramming technique may improve the efficiency or frequency of normal development of SCNT embryos. Here we hypothesized that treatment of somatic cells with extracts prepared from GV stage sturgeon's oocytes prior to their use as nuclear donors for SCNT will improve subsequent development. We reported a reversible permeabilization protocol with digitonin to deliver sturgeon oocyte exteact (SOE) to porcine fetal fibroblast cell nuclei ex ovo. Porcine fibroblasts were permeabilized by 4 μg/ml of digitonin for 2 min at 4℃ and then incubated in SOE for 7h at 15 18℃ followed by resealing of cell membrane. As results, no difference was observed in the number of fused couplets or the number of fused couplets that cleaved between the extract treated or control group. However, there was a significantly decrease in the percentage of fused couplets that developed to the blastocyst stage in the SOE treated group (p<0.05). Histone acetylation status was determined using an antibody to acetylation at lysine 9 on histone 3 (H3K9Ac). The intensity of H3K9Ac staining in 1-cell stage NT embryos was significantly increased when treated with the SOE (p<0.05), similar to that in 1-cell stage IVF embryos. In addition, porcine NT embryos reconstructed by using donor cell exposed to SOE prior to cell fusion significantly decreased developmental competence to the blastocyst stage but increased pluripotent gene expressions (Sox2, Nanog and Oct3/4) when compared with those in normal NT embryos (p<0.05).
Autophagy, the process of bulk degradation and recycling of long-lived proteins, macromolecular aggregates, and damaged intracellular organelles, has recently been shown to be important for pre-implantation development and cavitation in mouse embryos. This study investigated the occurrence of autophagy and its importance in determining the in vitro development of pig embryos produced by in vitro fertilization (IVF) or parthenogenetic activation (PA). Western blot analysis for autophagy marker, microtubule associated protein light chain 3 (MAP-LC3), revealed the temporal pattern of LC3-conversion with intense changes during 10 20 h post-insemination and at morula-blastocyst transition in pig embryos. Specific inhibition of autophagy in 2 4 cell stage pig embryos, by treatment with 3-methyladenine (3MA), did not affect their embryonic development up to morula stage (p>0.05) but completely blocked their progression to the blastocyst stage (0.0±0.0 vs. 28.5±1.7% p<0.05). On the other hand, autophagy-inhibition in morula stage embryos significantly inhibited the formation of blastocoel (14.9±3.6 vs. 37.5±7.2%) and reduced the proportion of expanded blastocysts (5.6±2.6 vs. 29.6± 4.6% p<0.05). TUNEL assay revealed that autophagy-inhibited embryos had significantly increased indices of apoptosis (10.2±0.4 vs. 2.3±0.2) and DNA fragmentation (0.8± 0.1 vs. 0.3±0.1) than those of controls (p<0.05). Interestingly, while anti-oxidants reduced (p<0.05) the apoptosis and improved the blastocyst formation rate in pig embryos, it had no influence (p>0.05) on the expression of MAP-LC3. These data therefore, suggest that autophagy may have essential role during blastocyst formation in pig embryos.
Autophagy is a process of intracellular bulk protein degradation, in which the accumulated proteins and cytoplasmic organelles are degraded. It plays important roles in cellular homeostasis, apoptosis, and development, but its role during early embryo development remains contentious. Therefore, in the present study, we investigated the effects of 3-methyladenine (3-MA) on early embryonic development in pigs. we also investigated several indicators of developmental potential, including mitochondrial distribution, genes expressions (autophagy-, apoptosis- related genes), apoptosis and ER-stress, which are affected by 3-MA. After in vitro maturation and fertilization, presumptive pig embryos were cultured in PZM-3 medium supplemented with 3-MA for 2 days at 39℃, 5% CO2 in air. Developmental competence to the blastocyst stage in the presence of 3-MA was gradually decreased according to increasing concentration. Thus, all further experiments were performed using 2 mM 3-MA. Blastocysts that developed in the 3-MA treated group decreased LC3-II intensity and expressions of autophagy related genes than those of the untreated control, resulting in down-regulates the autophagy. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 3-MA treated group compared with control (6.0±1.0 vs 3.3±0.6, p<0.05). Also, the expression of the pro-apoptotic gene Bax increased in 3-MA treated group, whereas expression of the anti-apoptotic gene Bcl-XL decreased. Mito Tracker Green FM staining showed that blastocysts derived from the 3-MA treated group had lower mitochondrial integrity than that of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. Then, the expression of the spliced form of pXBP-1 product (pXBP-1s) increased in 3-MA treated group, resulting increase of ERstress. Taken together, these results indicate that inhibition of autophagy by 3-MA is closely associated with apoptosis and ER-stress during preimplantation periods of porcine embryos.
본 연구에서는 OPU를 통한 체내 유래 난자를 이용한 수정란 생산 시 1개월에서 6개월까지의 연구 기간에 따른 난포 생성수, 난자 회수율, 난자 등급율, 배반포 생성률을 분석하여 공란우의 활용 기간에 관하여 조사하였다. 1. 채란 기간에 따른 난포 생성수는 1개월에서 5개월까지의 난포 생성수는 , , , , 개로 유의적인 차이가 없었으나, 6개월째에는개로 급격하게 줄어든 것을 알 수 있었다. 2. 채란 기간에 따른 난자 회수개수는 1개월에서 3개월까지는
본 연구는 체외 성숙된 난자와 동결 융해 정자를 이용한 돼지의 체외 수정 과정에서 난구 세포의 존재가 정자 침투율, 웅성전핵 형성률 그리고 후기배로의 체외 발육에 미치는 영향을 알아보기 위하여 수행되었다. 돼지 난소로부터 난자-난구세포 복합체를 채취하여 eCG/hCG, 10% 돼지 난포액, epidermal growth factor 등이 첨가된 TCM 199 배양액에서 44시간 배양하여 체외 성숙을 유도하였다. 성숙 배양 후 난구 세포를 제거한 난자와
본 연구는 수정란이식의 현장 적용 측면을 중심으로, 한우 체외 수정란의 발생 단계, 일자 및 등급이 젖소 대리모에 이식 후 임신과 유산, 분만과 관련된 임신기간, 생시체중, 난산 및 쌍자율을 조사하였다. 또한 단자 및 쌍자 분만에 따른 임신기간, 생시체중, 성비 및 폐사율을 분석하였다. 발생 단계에 따른 임신율은 배반포 단계(64.4%), 유산율은 부화 배반포(HB) 단계(21.4%)가 유의하게 높았다(p<0.05). 발생 일령에 따른 임신율은 7일령