Philipsen J N, Gruber M, Ab G
Biochim Biophys Acta. 1985 Dec 18;826(4):186-94. doi: 10.1016/0167-4781(85)90005-3.
We have studied the methylation status of the estradiol-controlled chicken vitellogenin (Vtg) gene, which is expressed in the liver. A 30-kb region was investigated, containing 17 HpaII and 18 HhaI sites, of which 21 are in the 22-kb gene. Of these 21 sites, 9 were found to be demethylated in laying-hen liver relative to immature chicken liver. Outside the transcribed region, only one site was found to be relatively undermethylated in laying-hen liver. This site, at 0.6 kb in front of the gene, is, as shown earlier, also demethylated in rooster or immature chicken liver upon primary hormone stimulation, as well as in the non-expressing estradiol target organ oviduct. In this respect, this site sharply contrasts with those in the transcribed region, which appear to become demethylated only upon prolonged transcription of the gene.
我们研究了在肝脏中表达的雌二醇调控的鸡卵黄蛋白原（Vtg）基因的甲基化状态。研究了一个30kb的区域，其中包含17个HpaII和18个HhaI位点，其中21个位于22kb的基因中。在这21个位点中，相对于未成熟鸡肝脏，发现9个位点在产蛋母鸡肝脏中去甲基化。在转录区域之外，仅发现一个位点在产蛋母鸡肝脏中相对低甲基化。如前所示，该位点位于基因前方0.6kb处，在原代激素刺激后，在公鸡或未成熟鸡肝脏以及非表达雌二醇靶器官输卵管中也去甲基化。在这方面，该位点与转录区域中的位点形成鲜明对比，转录区域中的位点似乎仅在基因长时间转录后才去甲基化。
