Stutz A, Conne B, Huarte J, Gubler P, Völkel V, Flandin P, Vassalli J D
Department of Morphology, University of Geneva Medical School, 1211 Geneva 4, Switzerland.
Genes Dev. 1998 Aug 15;12(16):2535-48. doi: 10.1101/gad.12.16.2535.
The mechanisms responsible for translational silencing of certain mRNAs in growing oocytes, and for their awakening during meiotic maturation, are not completely elucidated. We show that binding of a approximately 80-kD protein to a UA-rich element in the 3' UTR of tissue-type plasminogen activator mRNA, a mouse oocyte mRNA that is translated during meiotic maturation, silences the mRNA in primary oocytes. Translation can be triggered by injecting a competitor transcript that displaces this silencing factor, without elongation of a pre-existing short poly(A) tail, the presence of which is mandatory. During meiotic maturation, cytoplasmic polyadenylation is necessary to maintain a poly(A) tail, but the determining event for translational activation appears to be the modification or displacement of the silencing factor.
导致生长中的卵母细胞某些mRNA翻译沉默以及减数分裂成熟过程中这些mRNA“唤醒”的机制尚未完全阐明。我们发现,一种约80-kD的蛋白质与组织型纤溶酶原激活物mRNA 3'UTR中富含UA的元件结合,该mRNA是一种在减数分裂成熟过程中进行翻译的小鼠卵母细胞mRNA,会使初级卵母细胞中的mRNA沉默。通过注射能取代这种沉默因子的竞争转录本可触发翻译,而无需延长预先存在的短聚腺苷酸尾,聚腺苷酸尾的存在是必需的。在减数分裂成熟过程中,细胞质聚腺苷酸化对于维持聚腺苷酸尾是必要的,但翻译激活的决定性事件似乎是沉默因子的修饰或取代。