Lipopolysaccharide (LPS) is an endotoxin factor present in the cell wall of Gram-negative bacteria and induces various immune responses to infection. Recent studies have reported that LPS induces cellular stress in various cells including oocytes and embryos. Melatonin (N-acetyl-5-methoxytryptamine) is a regulatory hormone of circadian rhythm and a powerful antioxidant. It has been known that melatonin has an effective function in scavenging oxygen free radicals and has been used as an antioxidant to reduce the cytotoxic effects induced by LPS. However, the effect of melatonin on LPS treated early embryonic development has not yet been confirmed. In this study, we cultured mouse embryos in medium supplemented with LPS or/and melatonin up to the blastocyst stage in vitro and then evaluated the developmental rate. As a result of the LPS-treatment, the rate of blastocyst development was significantly reduced compared to the control group in all the LPS groups. Next, in the melatonin only treated group, there was no statistical difference in embryonic development and no toxic effects were observed. And then we found that the treatment of melatonin improved the rates of compaction and blastocyst development of LPS-treated embryos. In addition, we showed that melatonin treatment decreased ROS levels compared to the LPS only treated group. In conclusion, we demonstrated the protective effect of melatonin on the embryonic developmental rate reduced by LPS. These results suggest a direction to improve reproduction loss that may occur due to LPS exposure and bacterial infection through the using of melatonin during in vitro culture.

Partheno Embryo's research is known to play a very important role in identifying the development of embryonic cells or analyzing the genetic mechanisms of embryonic development, but the information on apoptosis formed during the early stage of development on Partheno Embryo is very little. Therefore, this study analyzed whether the embryonic cell death of unit embryos can be inhibited by adding Scriptaid, one of HDACi, which plays a role in demethylation of histone proteins as a method of regulating the cell cycle in the early embryo development of Partheno Embryo. As a result, the differentiation rate was higher in the group that added Scriptaid and FBS, but the cellular development was higher in the group that added pregnant serum to Scriptaid. As a result of analyzing the expression of the gene through IF and PCR, the group with the addition of gestational serum increased the expression of BCL2 and PCNA, which affects the anti-Casp3 action in cell survival. In addition, it is interpreted that treatment of Scriptaid for 16 hours, rather than 24 h treatment lowers the expression of Casp-3, a representative factor of apoptosis, and also increases embryonic development, thus affecting early embryo development. Therefore, it is concluded that the 16-hour treatment of Scriptaid and the use of gestational serum will inhibit cell death in the early embryonic development and increase the development rate of the embryo.

This study was investigated to test whether the zygote recognized the topoisomerase II beta (TOP2B) mediated DNA fragmentation in epididymal spermatozoa or the nuclease degradation in vas deferens spermatozoa by testing for the presence of gammaH2AX (γH2AX). The γH2AX is phosphorylation of histone protein H2AX on serine 139 occurs at sites flanking DNA double-stranded breaks (DSBs). The presence of γH2AX in the pronuclei of mouse zygotes which were injected with DNA broke epididymal spermatozoa was tested by immunohistochemistry at 5 and 9 h post fertilization, respectively. Paternal pronuclei that arose from epididymal spermatozoa treated with divalent cations did not stain for γH2AX at 5 h. On the other hand, in embryos injected with vas deferences spermatozoa that had been treated with divalent cations, γH2AX was only present in paternal pronuclei, and not the maternal pronuclei at 5 h. Interestingly, both pronuclei stained positively for γH2AX for all treatments and controls at 9 h after sperm injection. In conclusion, the embryos recognize DNA that is damaged by nuclease, but not by TOP2B because H2AX in phosphorylated in paternal pronuclei resulting from spermatozoa treated with fragmented DNA from vas deferens spermatozoa treated with divalent cations, but not from epididymal spermatozoa treated the same way.

The aims of this study are to establish a stable isolation method of blastomeres from bovine early embryos and examine their developmental potential in vitro Early embryos were produced by maturation and fertilizaion in vitro of bovine follicular oocytes. Blastomeres were isolated from 2~8-cell embryos in +-, +-free PBS+EDTA after removing the zonae pellucidae Isolated blastomeres were cultured in CZB containing BOEC for upto 240 hpi. Cleavage rates of them were 18.5%(10 /54) in 1 /2 blastomeres, 33.3%(16/48) in 1/4 blastomeres and 34.2%(14 /41) in 1/8 blastomeres, respectively. The rates of blastocystic vesicle formed were 8.7%(4 /46) in 1/2 blastomeres, 26.6% (17/64) in 1/4 blastomeres and 10.3%(8 /78) in 1/8 blastomeres, respectively. Blastomeres developed into various types of blastocystic vesicles and trophoblastic vesicles as evidenced by the Hoechst 33258 staining and morphology. This results suggest that the isolation method used and subsequent culture of isolated blastomeres from bovine early embryos should be useful to obtain extra embryonic cells for various analyses such as PCR and putative ES cell culture.

This study was performed to establish the condition and the methods for the techniques of insertion the isolated blastomere cells into cytoplasm, in order to research the develop-mental ability of bovine embryo blastomere cells in vitro produced. After 24h in vitro ovary maturation with the ovaries from a slaughter house, in vitro fertilization was performed to the vital sperms which their mobility were decided by percoll gradient method, with 2~8 cell stage embryos, the blastomeres were isolated in +. +-free PBS, and following that embedded into agar and alginate solution, respectively. The rates of in vitro develop-ment are as follows ; in agar embedded 11 among 120(9.2%) 1 /2~1 /3 blastomers cleaved and 6 among 93(6.5%) 1 /4~1 /8 blastomeres cleaved. In sodium alginate-embedded 14 among 84(16.7%) 1 /2~1 /3 blastomeres cleaved and 6 among 85(7.1%) 1 /4~1 /8 blastomeres cleaved. In case of Na-alginate, the rate of the cells were better than those of agar. The results suggest that the techniques for embeeding the isolated blastomeres into gel may help cloning of bovine early embryo without nuclear transplantation.

Early maturing glutinous rice lines with giant embryo were developed using anther culture. Deuraechan, mid-late maturing high-yielding japonica rice variety with resistance against rice stipe virus (RSV), bacterial blight (BB), and lodging, and Chenghyangna ge, early maturing glutinous rice germplasm with giant embryo were used the parents. F2 seeds from the cross between Deuraechan and Chenghyangna ge with glutinous endosperm and giant embryo were selected and propagated to F2 population. In F2 population, anther culture was conducted using the panicles from the early maturing plants. All doubled haploid (DH) lines showed early maturing, glutinous endosperm, and giant embryo phenotype. Through marker-assisted selections to Stvb-i and Xa3, 17 DH lines carrying both resistance genes were selected. Among 17 DH lines, six lines with more embryo size and better agronomic traits were selected and analyzed their characteristics. These lines were early maturing glutinous rice with giant embryo and showed enhanced yield, resistance against RSV and BB, and lodging, compared to previously developed giant embryo rice varieties. But they were vulnerable to preharvest sprouting which is important trait in early maturing rice. According to the texture and rapid viscosity analysis, DH lines were considered to have appropriate properties of cooked brown rice. They showed less hardness, gummniess, chewiness, and setback. Developed DH lines could be useful materials for diversification of cropping system and enhancing the brown rice consumption but the breeding efforts to improve the vulnerability against preharvest sprouting is required to apply for practical variety.

p63은 다양한 상피 조직의 줄기세포와 전구세포에 존재한다는 사실이 잘 알려져 있으나, 치아 형성, 특히 사기질과 뿌리 형성시기에서의 p63 위치느 ㄴ아직 연구해야 할 과제로 남아 있다. 본 연구에서는 p63이 치아 발생 동안 치아상피에 편재하여 나타나는 것을 면역조직화학 기법을 이용하여 확인하였다. p63은 피부, 모낭, 구강점막 그리고 턱밑샘 도관을 포함하는 상피의 바닥층과 바닥위층에 위치하였다. 그러나 치아 부위에서는 치아관의 모든 세포, 사기질기