title: Embryo transcriptome response to environmental factors: implication for its survival under suboptimal conditions.
abstract: After its formation, the mammalian zygote undergoes a series of morphological, physiological and biochemical alterations prior to undergoing cell differentiation. The zygote is then transformed into a complex multicellular organism in a defined time window which may differ between species. These orderly embryonic developmental events are tightly regulated by temporal and spatial activation and/or deactivation of genes and gene products. This phenomenon may in turn be dependent on the intrinsic characteristics of the embryo itself, the physiological and biochemical composition of the maternal environment or by in vitro culture condition. In fact, when embryos are subjected to suboptimal culture condition, some of the embryos may escape the environmental stress by activating certain transcripts and some others which are unable to activate anti-stress agents may die or exhibit abnormal development. This phenomenon may partly depend on transcripts and proteins stored during oogenesis. Indeed after embryonic genome activation, the embryo destiny is governed by its own transcripts and protein synthesized over time. Therefore, this review begins by highlighting the type and quality of transcripts accumulated or degraded during oogenesis and its impact on the embryo survival. Thereafter, emphasis is given to the transcriptome response of preimplantation embryos to suboptimal culture conditions. In addition, the long term effect of preimplantation culture environment on the transcriptome response embryos/fetus during peri and post implantation has been addressed. Finally, a brief summary of the epigenetic control of culture induced genetic variation of the embryos has been highlighted.
authors: Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany.
authors: Dessie
authors: D
authors: Salilew-Wondim
authors: Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany. Electronic address: tesfaye@itw.uni-bonn.de.
authors: Dawit
authors: D
authors: Tesfaye
authors: Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany.
authors: Michael
authors: M
authors: Hoelker
authors: Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Endenicher Allee 15, 53115 Bonn, Germany.
authors: Karl
authors: K
authors: Schellander
mesh_terms: D000818:Animals; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000378:metabolism*; D044127:Epigenesis, Genetic / Q000187:drug effects* / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D059467:Transcriptome / Q000187:drug effects*
keywords: Culture; Embryo; Implantation; Preimplantation; Transcriptome