원문정보
초록
영어
Insulin-like growth factor II (IGF2) and H19 genes are mutually imprinted genes which may be responsible for abnormalities in the cloned fetuses and offspring. This study was performed to identify putative differentially methylated regions (DMRs) of porcine H19 locus and to explore its genomic imprinting in in vitro fertilized (IVF) and somatic cell nuclear transferred (SCNT) embryos. Based on mice genomic data, we identified DMRs on H19 and found porcine H19 DMRs that included three CTCF binding sites. Methylation patterns in IVF and SCNT embryos at the 2-, 4-, 8~16-cells and blastocyst stages were analyzed by BS (Bisulfite Sequencing)-PCR. The CpGs in CTCF1 was significantly unmethylated in the 2-cell stage IVF embryos. However, the 4- (29.1%) and 8~16-cell (68.2%) and blastocyst (48.2%) stages showed higher methylation levels (p<0.01). On the other hand, SCNT embryos were unmethylayted (0~2%) at all stages of development. The CpGs in CTCF2 showed almost unmethylation levels at the 2-, 4- and 8~16-cell and blastocyst stages of development in both IVF (0~14.1%) and SCNT (0~6.4%) embryos. At all stages of development, CTCF3 was unmethylated in IVF (0~17.3%) and SCNT (0~1.2%) embryos except at the blastocyst stage (54.5%) of IVF embryos. In conclusion, porcine SCNT embryos showed an aberrant methylation pattern comprised to IVF embryos. Therefore, we suggest that the aberrant methylation pattern of H19 loci may be a reason for increased abnormal fetus after embryo transfer of porcine SCNT embryos.
목차
INTRIDUSTION
MATERIALS AND METHODS
oocyte Retrieval and In Vitro Maturation
In Vitro Fertilization(IVF) of Oocytes
Preparation of Donor Cells for Nuclear Transfer
Somatic Cell Nuclear Transfer(SCNT) of Oocytes
Comparative Sequencing
Genomic DNA Isolation
Bisulfite(BS) Treatment and Polymerase Chain Reaction(PCR)
Cloning and sequencing
Experimental Designs
Statistical Analysis
RESULTS
Sequence Homology
Bisulfite Sequencing Analysis of Putative DMRs
Bisulfite Sequencing Analysis of Pocine IVF and SCNT Embryos
DISCUSSION
REFERENCES