Molecular mechanisms and pathways involved in bovine embryonic genome activation and their regulation by alternative in vivo and in vitro culture conditions.
Understanding gene expression patterns in response to altered environmental conditions at different time points of the preimplantation period would improve our knowledge on regulation of embryonic development. Here we aimed to examine the effect of alternative in vivo and in vitro culture conditions at the time of major embryonic genome activation (EGA) on the development and transcriptome profile of bovine blastocysts. Four different blastocyst groups were produced under alternative in vivo and in vitro culture conditions before or after major EGA. Completely in vitro- and in vivo-produced blastocysts were used as controls. We compared gene expression patterns between each blastocyst group and in vivo blastocyst control group using EmbryoGENE's bovine microarray. The data showed that changing culture conditions from in vivo to in vitro or vice versa, either before or after the time of major EGA, had no effect on the developmental rates; however, in vitro conditions during that time critically influenced the transcriptome of the blastocysts produced. The source of oocyte had a critical effect on developmental rates and the ability of the embryo to react to changing culture conditions. Ontological classification highlighted a marked contrast in expression patterns for lipid metabolism and oxidative stress response between blastocysts generated in vivo versus in vitro, with opposite trends. Molecular mechanisms and pathways that are influenced by altered culture conditions during EGA were defined. These results will help in the development of new strategies to modify culture conditions at this critical stage to enhance the development of competent blastocysts.
Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Germany.
Ahmed
A
Gad
Michael
M
Hoelker
Urban
U
Besenfelder
Vitezslav
V
Havlicek
Ulas
U
Cinar
Franca
F
Rings
Eva
E
Held
Isabelle
I
Dufort
Marc-André
MA
Sirard
Karl
K
Schellander
Dawit
D
Tesfaye
D000818:Animals; D002417:Cattle / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D047108:Embryonic Development / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D053263:Gene Regulatory Networks; D016678:Genome / Q000187:drug effects / Q000502:physiology; D046228:Microarray Analysis; D011247:Pregnancy; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D054928:Validation Studies as Topic
D003470:Culture Media