earticle

영어

SETD2 (SET domain containing protein 2) is known as a histone H3 lysine 36 (H3K- 36)-specific methyl-transferase, and suggesting that it has an important role in gene active transcription in human cells. In the current study, to investigate the dynamic change of SETD2 in pig, we determined the SETD2 expression in porcine fetal fibroblasts, oocytes and preimplantation embryos derived from in vitro fertilization (IVF), parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) by immunofluorescence using specific antibodies and laser scanning confocal microscopy. In porcine fetal fibroblasts, SETD2 expression was detected in inter phase, not in M (mitosis) phase. SETD2 signal was observed in non-surrounded nucleolus (NSN) stage oocytes. However, there were no signals were detected in surrounded nucleolus (SN), metaphase I (MI), and metaphase II (MII) stage oocytes. In IVF embryos, SETD2 signal was detectable in sperm, but this signal was lost after fertilization, and then became detectable at 2-cell stage, peaked at the 4-cell stage which is porcine embryonic gene activation time. Similar to the pattern found in IVF embryos, SETD2 signal in PA embryo was not detected at 1-cell stage, but detected at 2-cell stage, and maintained to blastocyst stage. Interestingly, unlike IVF and PA embryos, SETD2 signal could not be lost in 1-cell stage of SCNT embryos, and this signal was detectable in whole SCNT embryonic developmental stage. Overall, these data indicated that the SETD2 may be a mark of embryonic gene activation in porcine preimplantation embryos. Aberrant SETD2 expression occur in 1-cell stage of porcine SCNT embryos may be a factor of inducing low of cloning.