Qualitative patterns of protein synthesis in the preimplantation mouse embryo: I. Normal pregnancy☆

[摘要] QualitativepatternsofproteinsynthesisinpreimplantationmouseembryoswereexaminedbySDS-polyacrylamide-gelelectrophoresisfollowedbyautoradiography.Theresultsdemonstratethatthequalitativepatternofproteinsynthesisinnewlyfertilizedeggs(day1)isverysimilartotheproteinpatternobtainedfromovulated,unfertilizedeggs.Bylateday1orearlyday2,mostofthese“maternal”proteinsarenolongerbeingsynthesizedbytheembryo,andmanynewautoradiographicbandsareapparent.Themostintriguingaspectofthisstudyistheobservationthatallmajorchangesinthequalitativepatternofproteinsynthesistakeplacebetweenfertilizationandthefour-toeight-cellstage(day3).Fromearlyday3onward,thequalitativepatternofproteinsynthesisremainsessentiallyunchanged.Manyofthemajorautoradiographicbandsobservedinmouseembryosfromthefour-toeight-cellstageandonwardarealsoobservedinproteinpatternsobtainedfromblastocyst-stagerabbitembryos.Thechangingpatternsofproteinsynthesisrevealedinthisstudyoccurbeforeanygrossdifferentiationoftheembryosisevident(delineationoftheinnercellmassandtrophoblast)andbeforeamarkedincreaseintherelativerateofincorporationofl-[35S]methioninetakesplace.However,thequalitativechangesinthepatternofproteinsynthesisdocoincidewithaperiodofextensivefinestructuraldifferentiation.

[学科分类] 生物科学（综合）