Interspecies somatic cell nuclear transfer (iSCNT) is a valuable tool for studying the interactions between an oocyte and somatic nucleus. The object of this study was to investigate the developmental competence of in vitro‐matured porcine oocytes after transfer of the somatic cell nuclei of 2 different species (goat and rabbit). Porcine cumulus oocytes were obtained from the follicles of ovaries and matured in TCM‐199. The reconstructed embryos were electrically fused with 2 DC pulses of 1.1 kV/cm for 30 μs in 0.3 M mannitol medium. The activated cloned embryos were cultured in porcine zygote medium‐3 (PZM‐3), mSOF or RDH medium for 7 days. The blastocyst formation rate of the embryos reconstructed from goat or rabbit fetal fibroblasts was significantly lower than that of the embryos reconstructed from porcine fetal fibroblast cells. However, a significantly higher number of embryos reconstructed from goat or rabbit fetal fibroblasts cultured in mSOF or RDH, respectively, developed to the morular stage than those cultured in PZM‐3. These results suggest that goat and bovine fetal fibroblasts were less efficacious than porcine‐porcine cloned embryos and that culture condition could be an important factor in iSCNT. The lower developmental potential of goat‐porcine and porcine‐bovine cloned embryos may be due to incompatibility between the porcine oocyte cytoplasm and goat and bovine somatic nuclei.

Insulin, transferrin and selenium (ITS) complex is reported to improve in vitro development of oocytes and embryos. This study was carried out to investigate the effects of ITS during in vitro culture (IVC) of porcine parthenogenetic and nuclear transfer (NT) embryos on subsequent developmental capacity in vitro. The electrically activated oocytes were cultured in Porcine Zygote Medium (PZM-3) with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 7 days. Also, the electrically activated reconstructed embryos were cultured in PZM-3 with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 6 days. Addition of ITS to culture medium did not affect development of porcine parthenogenetic embryos in vitro. To test the effect of ITS on the in vitro development of porcine NT embryos, factorial experiments were also performed for in vitro maturation (IVM) medium (TCM-199) with or without 1% ITS and culture medium (PZM-3) with or without 0.5% ITS. Addition of 0.5% ITS to culture medium increased (p<0.05) the proportion of NT blastocysts compared with non-treated group. In contrast, addition of 1% ITS to culture medium was ineffective or had a detrimental effect. Also, addition of ITS only to maturation medium increased (p<0.05) the percentage of NT blastocysts formation compared with the control group. In conclusion, addition of ITS to IVM or IVC medium could improve subsequent blastocyst development of porcine NT embryos.

To examine the differential protein expression pattern in the 11.5 day post-coitus (dpc) and 18.5 dpc placenta of mouse, we have used the global proteomics approach by 2-D gel electrophoresis (2-DE) and MALDI-TOF-MS. The differential protein patterns of 3 placentae at the 11.5 dpc and 18.5 dpc from nature mating mice were analyzed. Proteins within isoelectric point range of 3.0~10.0, separately were analyzed in 2DE with 3 replications of each sample. A total of approximately 1,600 spots were detected in placental 2-D gel stained with Coomassie-blue. In the comparison of 11.5 dpc and 18.5 dpc placentae, a total of 108 spots were identified as differentially expressed proteins, of which 51 spots were up-regulated proteins such as alpha-fetoprotein, mKIAA0635 protein and transferrin, annexin A5, while 48 spots were down-regulated proteins such as Pre-B-cell colony-enhancing factor 1(PBEF), aldolase 1, A isoform, while 4 spots were 11.5 dpc specific proteins such as chaperonin and Acidic ribosomal phosphoprotein P0, while 3 spots were 18.5 dpc specific proteins such as aldo-keto reductase family 1, member B7 and CAST1/ERC2 splicing variant-1. Most identified proteins in this analysis appeared to be related with catabolism, cell growth, metabolism and regulation. Our results revealed composite profiles of key proteins involved in mouse placenta during pregnancy.