Extrapancreatic insulin gene expression in the fetal rat.
Extrapancreatic insulin gene expression in the fetal rat.
复制标题
胎鼠胰外胰岛素基因表达。
DOI：
10.1073/pnas.81.12.3635
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发表时间：
1984
影响因子：
11.1
通讯作者：
Locker,J
中科院分区：
文献类型：
--
作者：
Muglia,L;Locker,J
对大鼠卵黄囊（一种原始的内胚层结构）基因表达的分析显示，发育调节的胰岛素产生水平较低。在妊娠14天时，2.4-核糖核酸酶（kb）RNA种类与克隆的胰岛素基因探针杂交。该物种在整个妊娠期增加。在第16天，第二个0.72 kb的转录变得可见，到第18天，0.72 kb的转录占主导地位。在胰腺中，完全加工的胰岛素mRNA长0.55 kb。在同一时间段内，在胎儿肝脏（也是内胚层起源的组织，如胰腺），只有2.4 kb的转录本被检测到，没有杂交转录本被检测到成人肝脏RNA。酸/乙醇可溶性肽的凝胶过滤研究和胰岛素放射免疫分析显示，在18天的卵黄囊中，胰岛素原和胰岛素的量大致相等，这一结果表明，在该组织中的转录本被翻译。另一方面，较低水平的胰岛素和缺乏胰岛素原在胎肝是兼容的胰腺起源的肝细胞胰岛素受体结合，而不是肝内胰岛素合成。
Analysis of gene expression in rat yolk sac, a primitive endodermal structure, revealed a low level of developmentally regulated insulin production. At 14 days of gestation, a 2.4-kilobase (kb) RNA species hybridized to cloned insulin gene probes. This species increased throughout gestation. At 16 days, a second transcript of 0.72 kb became visible and, by 18 days, the 0.72-kb transcript predominated. In the pancreas, the fully processed insulin mRNA is 0.55 kb long. Over the same time period in the fetal liver (also a tissue of endodermal origin, as is the pancreas), only the 2.4-kb transcript was detected; no hybridizing transcripts were detected in adult liver RNA. Gel filtration studies and insulin radioimmunoassay of acid/ethanol-soluble peptides showed approximately equal amounts of proinsulin and insulin in 18-day yolk sac, a result suggesting that the transcripts in this tissue are translated. On the other hand, a lower level of insulin and the lack of proinsulin in fetal liver were compatible with a pancreatic origin of hepatocyte insulin by receptor binding rather than intrahepatic insulin synthesis.