Glucose Metabolism During Kunming Mouse Preimplantation Development:Analysis of Gene Transcription in Embryos in Vivo

昆明小鼠体内发育早期胚胎葡萄糖代谢关键酶转录产物的分析

In order to investigate glucose metabolism pathways and their changes in Kunming mouse preimplantation 1-,2-,4-,8-cell,and morula embryos,the mRNA level for the genes involved in glucose metabolism was tested by nested RT-PCR on embryos at different development stages in vivo.These genes were glucose 6-phosphate dehydrogenase(G6PDH),phospho-fructokinase(PFK),and phosphoglucomutase(PGM),representing pentose phosphate pathway(PPP),glycolysis,and glycogensis and glycogenolysis respectively.Three sets of inner and outer primers were designed and synthesized based on cDNA sequences of G6PDH,PFK and PGM.RT-PCR results revealed that G6PDH gene transcription was found in Kunming mouse 1-8 cell embryos,and not in morula embryos;it indicated that 1-8 cell embryos may metabolize glucose by pentose phosphate pathway,but morula embryos can not do so.PFK gene transcription was found in 1-8 cell and morula embryos;it is probable that there exists glycolysis in those embryos.PGM gene transcription was not found in 1-8 cell and morula embryos,so glycogenesis and glycogenolysis in these embryos were not present.

首次报道了昆明小鼠体内发育的早期胚胎1-细胞至桑椹期阶段葡萄糖代谢的3种关键酶———6-磷酸葡萄糖脱氢酶(G6PDH)、6-磷酸果糖激酶(PFK)和磷酸葡萄糖变位酶(PGM)的基因转录情况,其分别体现了磷酸戊糖、糖酵解、糖原的合成和分解等途径。根据G6PDH、PFK、PGM的cDNA序列分别设计和合成3套共6对内、外引物,采用巢式RT PCR方法对其进行检测。结果表明:早期胚胎1~8细胞阶段均有G6PDH基因的转录,桑椹期胚胎不存在该基因的转录,说明早期胚胎1~8细胞阶段可能存在磷酸戊糖,而桑椹期则不存在;1-细胞至桑椹期均存在PFK基因的转录,说明该阶段的胚胎可能存在糖酵解代谢途径;1-细胞至桑椹期均不存在PGM基因的转录,说明该阶段的胚胎可能不存在糖原的合成与分解代谢途径。