Ut hormones and cultured for an UKI 1 site additional 22 h at 38.5uC in an atmosphere containing 5 CO2 and 100 humidity.In vitro Fertilization (IVF)Fertilization was performed as described in our previous study [27]. At 42 h of IVM, 15?0 denuded MII oocytes were placed in 40 ml drops of modified Tris-buffered medium (mTBM) that had been covered with warm mineral oil in a 60-mm dish. Fresh semen ejaculated from a Duroc boar was supplied by DARBY A.I. center (Chungju, South Korea). The semen sample was washed twice by centrifugation at 3506g for 3 min in phosphate-buffered saline (PBS). The sperm pellet was then resuspended and adjusted to a concentration of 16105 sperm/ml. The appropriate concentraX-Linked Gene Transcripts in Pig BlastocystsX-Linked Gene Transcripts in Pig BlastocystsFigure 8. X-linked gene transcription patterns of female and male porcine cloned blastocysts by treatment of Scriptaid, a HDACi after SCNT. A relative fold change of mRNA levels of female (Left panel) and male (right panel) cloned blastocysts compared with that of the in vivo female ones defined as 1. Asterisks indicate significant difference between in vivo and cloned groups (* P,0.05; ** P,0.01; *** P,0.001). doi:10.1371/journal.pone.0051398.gtion of sperm was introduced into the oocyte-containing medium drop and the cells were purchase 94-09-7 incubated for 6 h at 38.5uC. After fertilization, excess spermatozoa were removed from oocytes by a repetitive pipetting action, and fertilized oocytes were washed three times in a culture medium (PZM3) containing a 1 nonessential amino acid/minimum essential medium solution.Nuclear TransferBriefly, adult fibroblast cells were obtained from abdominal skin biopsy and 18297096 fetal fibroblast (pFF) cells were obtained from a day 27 pregnant Yucatan minipig that had mated naturally. The pFF cell lines, except for F2, were primarily characterized by the success rate of full-term development following SCNT (Table 2). The adult tissue samples were cut into small pieces (approx. 1 mm) with a scalpel. Then, the dissected tissues were cultured in Dulbecco’s modified Eagle’s medium (DMEM; Gibco-BRL, Grand Island, NY) with 10 fetal bovine serum until confluent; cells were frozen in DMEM with 10 fetal calf serum (FCS) and 10 dimethyl sulfoxide. Prior to use as nuclear donor cells, cells were thawed and cultured for 2? days in DMEM with 10 FCS. Nuclear transfer was performed as was previously described by Song et al. [45].Enucleation was carried out in TL EPES supplemented with 0.4 bovine serum albumin (BSA) and 5 mg/ml cytochalasin B. Denuded oocytes were enucleated by aspirating the polar body and MII chromosomes by an enucleation pipette (Humagen, Charlottesville, VA). After enucleation, a donor cell was introduced into the perivitelline space of an enucleated oocyte. Fusion of injected oocytes was induced in fusion medium (280 mM mannitol, 0.001 mM CaCl2, and 0.05 mM MgCl2) by two DC pulses (1-s interval) of 2.0 kV/cm for 30 ms using a BTX-Cell Manipulator 200 (BTX, San 1379592 Diego, CA). After fusion, oocytes were incubated for 1 h in TL EPES. The reconstructed oocytes were activated by an electric pulse (1.0 kV/cm for 60 ms) in activation medium (280 mM mannitol, 0.01 mM CaCl2, 0.05 mM MgCl2), followed by 4 h of incubation in PZM3 medium containing 2 mmol/l 6-dimethylaminopurine. Embryo transfers were performed at a research farm (Department of Livestock Research, Gyeonggi Veterinary Service, Korea). Approximately 100 reconstructed oocytes were surgically t.Ut hormones and cultured for an additional 22 h at 38.5uC in an atmosphere containing 5 CO2 and 100 humidity.In vitro Fertilization (IVF)Fertilization was performed as described in our previous study [27]. At 42 h of IVM, 15?0 denuded MII oocytes were placed in 40 ml drops of modified Tris-buffered medium (mTBM) that had been covered with warm mineral oil in a 60-mm dish. Fresh semen ejaculated from a Duroc boar was supplied by DARBY A.I. center (Chungju, South Korea). The semen sample was washed twice by centrifugation at 3506g for 3 min in phosphate-buffered saline (PBS). The sperm pellet was then resuspended and adjusted to a concentration of 16105 sperm/ml. The appropriate concentraX-Linked Gene Transcripts in Pig BlastocystsX-Linked Gene Transcripts in Pig BlastocystsFigure 8. X-linked gene transcription patterns of female and male porcine cloned blastocysts by treatment of Scriptaid, a HDACi after SCNT. A relative fold change of mRNA levels of female (Left panel) and male (right panel) cloned blastocysts compared with that of the in vivo female ones defined as 1. Asterisks indicate significant difference between in vivo and cloned groups (* P,0.05; ** P,0.01; *** P,0.001). doi:10.1371/journal.pone.0051398.gtion of sperm was introduced into the oocyte-containing medium drop and the cells were incubated for 6 h at 38.5uC. After fertilization, excess spermatozoa were removed from oocytes by a repetitive pipetting action, and fertilized oocytes were washed three times in a culture medium (PZM3) containing a 1 nonessential amino acid/minimum essential medium solution.Nuclear TransferBriefly, adult fibroblast cells were obtained from abdominal skin biopsy and 18297096 fetal fibroblast (pFF) cells were obtained from a day 27 pregnant Yucatan minipig that had mated naturally. The pFF cell lines, except for F2, were primarily characterized by the success rate of full-term development following SCNT (Table 2). The adult tissue samples were cut into small pieces (approx. 1 mm) with a scalpel. Then, the dissected tissues were cultured in Dulbecco’s modified Eagle’s medium (DMEM; Gibco-BRL, Grand Island, NY) with 10 fetal bovine serum until confluent; cells were frozen in DMEM with 10 fetal calf serum (FCS) and 10 dimethyl sulfoxide. Prior to use as nuclear donor cells, cells were thawed and cultured for 2? days in DMEM with 10 FCS. Nuclear transfer was performed as was previously described by Song et al. [45].Enucleation was carried out in TL EPES supplemented with 0.4 bovine serum albumin (BSA) and 5 mg/ml cytochalasin B. Denuded oocytes were enucleated by aspirating the polar body and MII chromosomes by an enucleation pipette (Humagen, Charlottesville, VA). After enucleation, a donor cell was introduced into the perivitelline space of an enucleated oocyte. Fusion of injected oocytes was induced in fusion medium (280 mM mannitol, 0.001 mM CaCl2, and 0.05 mM MgCl2) by two DC pulses (1-s interval) of 2.0 kV/cm for 30 ms using a BTX-Cell Manipulator 200 (BTX, San 1379592 Diego, CA). After fusion, oocytes were incubated for 1 h in TL EPES. The reconstructed oocytes were activated by an electric pulse (1.0 kV/cm for 60 ms) in activation medium (280 mM mannitol, 0.01 mM CaCl2, 0.05 mM MgCl2), followed by 4 h of incubation in PZM3 medium containing 2 mmol/l 6-dimethylaminopurine. Embryo transfers were performed at a research farm (Department of Livestock Research, Gyeonggi Veterinary Service, Korea). Approximately 100 reconstructed oocytes were surgically t.
