Navarrete Santos A, Augustin R, Lazzari G, Galli C, Sreenan J M, Fischer B
Department of Anatomy and Cell Biology, Martin Luther University Faculty of Medicine, Halle (Saale), Germany.
Biochem Biophys Res Commun. 2000 May 19;271(3):753-60. doi: 10.1006/bbrc.2000.2646.
We have investigated the expression of two glucose transporter isoforms, Glut1 and 4, in 14- and 16-day-old bovine blastocysts (d14, d16) using RT-PCR, competitive RT-PCR and in situ hybridization. The blastocysts were grown in vivo or had been produced in vitro. Glut1 mRNA was detected in all blastocysts studied, Glut4 in all d14 blastocysts, but only in a few d16 blastocysts. Glut4 mRNA was localized in trophoblast and endoderm cells. Glut1 mRNA increased from d14 to d16 while Glut4 transcription was down-regulated in d16 blastocysts. The mRNA amounts varied between 0.8 to 23 pg and 3.9 to 65 fg per 100 ng embryonic RNA for Glut1 and Glut4, respectively, displaying a 100- to 1500-fold lower expression of Glut4 compared with Glut1 during blastocyst elongation. This is the first report on the expression of the insulin-sensitive Glut4 isoform in mammalian preimplantation embryos.
我们运用逆转录聚合酶链反应（RT-PCR）、竞争性逆转录聚合酶链反应（competitive RT-PCR）以及原位杂交技术，对14日龄和16日龄牛囊胚（d14、d16）中两种葡萄糖转运蛋白异构体Glut1和Glut4的表达情况进行了研究。这些囊胚或是在体内发育，或是通过体外培养产生。在所研究的所有囊胚中均检测到了Glut1 mRNA，在所有d14囊胚中检测到了Glut4，但仅在少数d16囊胚中检测到。Glut4 mRNA定位于滋养层细胞和内胚层细胞。从d14到d16，Glut1 mRNA增加，而在d16囊胚中Glut4转录被下调。每100 ng胚胎RNA中，Glut1和Glut4的mRNA量分别在0.8至23 pg和3.9至65 fg之间变化，在囊胚伸长过程中，Glut4的表达比Glut1低100至1500倍。这是关于胰岛素敏感型Glut4异构体在哺乳动物植入前胚胎中表达的首次报道。
