Zingg H H, Lefebvre D L
Laboratory of Molecular Endocrinology, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
Mol Cell Endocrinol. 1989 Aug;65(1-2):59-62. doi: 10.1016/0303-7207(89)90165-2.
Earlier studies indicate that rat hypothalamic oxytocin (OT) mRNA accumulation rises gradually during pregnancy and remains elevated throughout the lactation period. Here we show that, in addition, hypothalamic OT mRNA undergoes a structural change during this period. On gel electrophoresis, the size of rat OT mRNA increased from 750 bases (control) to a maximum of 820 bases (7th day of lactation). Removal of the poly(A) tail by the RNase H methods revealed that this size increase can be fully accounted for by a prolongation of the polyadenylate tail. There is considerable evidence for a role of the poly(A) tail segment in augmenting mRNA stability and, possibly, translational efficiency. It is thus conceivable that the demonstrated regulation of OT mRNA poly(A) tail length represents an additional level of OT gene control during pregnancy and lactation.
早期研究表明，大鼠下丘脑催产素（OT）mRNA的积累在孕期逐渐增加，并在整个哺乳期一直保持在较高水平。在此我们还发现，在此期间下丘脑OT mRNA会发生结构变化。在凝胶电泳中，大鼠OT mRNA的大小从750个碱基（对照）增加到最大820个碱基（哺乳期第7天）。通过核糖核酸酶H方法去除多聚腺苷酸尾表明，这种大小增加完全是由于多聚腺苷酸尾的延长所致。有大量证据表明多聚腺苷酸尾片段在增强mRNA稳定性以及可能在翻译效率方面发挥作用。因此可以设想，所证实的OT mRNA多聚腺苷酸尾长度的调节代表了孕期和哺乳期OT基因控制的一个额外层面。
