Abstract
In the present study, we investigated differentially regulated proteins within porcine somatic cell nuclear transfer (SCNT)-derived conceptuses compared with conceptuses that were derived from natural matings on day 14 of pregnancy. On day 14 of pregnancy, the SCNT-derived conceptuses were smaller and appeared abnormal compared with the control conceptuses. In the proteomic analysis, 67 proteins were identified as being differentially regulated in the SCNT-derived conceptuses. Among these proteins, 61 were downregulated, whereas the other 6 proteins were upregulated. Among the downregulated proteins, glycolytic proteins, such as pyruvate dehydrogenase, malate dehydrogenase, lactate dehydrogenase, and isocitrate dehydrogenase 1, were identified in the SCNT-generated conceptuses. Proteomic analysis also showed that antioxidant enzymes, such as peroxiredoxin-4, oxidation resistance 1, and thioredoxin peroxidase II, were downregulated in the SCNT-derived conceptuses. Among the upregulated proteins, annexin V, Hsp60, lamin A, and aldehyde dehydrogenase 1, an apoptotic regulator that interacts with the key components of apoptotic signaling, were identified. These findings demonstrate that the conceptuses of the SCNT-derived embryos showed aberrant protein expression patterns during implantation.These observations strongly indicate that the developmental defects of the SCNT-derived embryos are caused, at least in part, by disruption of the developing conceptus, which occurs as a result of aberrant gene expression that causes abnormal apoptosis and metabolism.
