ABSTRACT
Polyploids are pervasive in plants and have large impacts on crop breeding, but natural polyploids are rare in animals. Mouse diploid embryos can be induced to become tetraploid by blastomere fusion at the 2-cell stage and tetraploid embryos can develop to the blastocyst stage in vitro. However, there is little information regarding mouse octaploid embryonic development and precise mechanisms contributing to octaploid embryonic developmental limitations are unknown. To investigate the genetic and epigenetic mechanisms underlying octaploid embryonic development, we generated mouse octaploid embryos and evaluated the in vitro/in vivo developmental potential. Here we show that octaploid embryos can develop to the blastocyst stage in vitro, but all fetus impaired immediately after implantation. Our results indicate that cell lineage specification of octaploid embryo was disorganized. Furthermore, these octaploid embryos showed increased apoptosis as well as alterations in epigenetic modifications when compared with diploid embryos. Thus, our cumulative data provide cues for why mouse octaploid embryonic development is limited and its failed postimplantation development.
Subject(s)
Apoptosis/genetics , Autophagy/genetics , Embryonic Development/genetics , Epigenesis, Genetic , Polyploidy , Animals , Biomarkers/metabolism , Blastocyst/cytology , Blastocyst/metabolism , Cell Lineage/genetics , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Female , Mice, Inbred ICR , Models, BiologicalABSTRACT
The orthologs have similar or even identical functions in different species, share the anological regulatory pathways, and play the close or even same role among species. Furthermore, the vast majority of the biological core functions were assumed to a considerable number of orthologous genes in organisms. Orthologs was the most reliable choices for functional annotation and analysis of genomic sequences, whose unique biological characteristics demonstrated that comparative genomics research based on orthologs will certainly provide clues for detecting the origin, expression, and loss of important functional genes during the biological evolution in different organisms. In this review, the fundamental characteristics of orthologous genes and the relationship between the orthologs and comparison genomics were recounted. The corresponding approaches and the current status in comparative genomic research based on the orthologs were summarized.
