Separate elements in the 3' untranslated region of the mouse protamine 1 mRNA regulate translational repression and activation during murine spermatogenesis
Separate elements in the 3' untranslated region of the mouse protamine 1 mRNA regulate translational repression and activation during murine spermatogenesis
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DOI：
10.1006/dbio.1997.8705
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发表时间：
1997-11-01
影响因子：
2.7
通讯作者：
Braun, RE
中科院分区：
文献类型：
--
作者：
Fajardo, MA;Haugen, HS;Braun, RE
小鼠精蛋白mrna、Prm-1和Prm-2在雄性生殖细胞分化过程中被翻译抑制数天。小鼠Prm-1 mRNA的翻译延迟先前已被证明依赖于位于Prm-1 3‘非翻译区（3’ UTR）的最后62个核苷酸的顺式作用元件。我们之前已经发现了一个48/50 kda的蛋白，它以序列特异性的方式结合Prm-1和Prm-2 mrna的3' utr，存在于减数分裂后圆形精子细胞的细胞质片段中，其中鱼精蛋白mrna是翻译沉默的，并且在细长精子细胞中显著减少，其中鱼精蛋白mrna被激活进行翻译。令人惊讶的是，这种活性的结合位点映射到Prm-1 3' UTR的一个区域，这个区域不包含在上面描述的62个功能性核苷酸中。在本报告中，我们发现48/50-kDa蛋白的结合位点也可以在体内延迟报告RNA的翻译，这表明48/50-kDa蛋白可以在小鼠精子发生过程中抑制Prm-1 mRNA的翻译。这一观察结果证明，Prm-1 3' UTR的两个独立区域足以抑制Prm-1的翻译。此外，免疫细胞化学和多体分析表明，这种转基因报告mRNA不能进行适当的翻译激活。这些结果表明，Prm-1 3' UTR的一个额外区域需要适当的翻译激活，并且Prm-1翻译抑制元件可以与参与翻译激活的元件分离。(C) 1997学术出版社。
The mouse protamine mRNAs, Prm-1 and Prm-2 are translationally repressed for several days during male germ cell differentiation. The translational delay of mouse Prm-1 mRNA has previously been shown to be dependent upon cis-acting elements that reside in the last 62 nucleotides of the Prm-1 3' untranslated region (3' UTR). We have previously identified a 48/50-kDa protein that binds the 3' UTRs of both Prm-1 and Prm-2 mRNAs in a sequence-specific manner, is present in cytoplasmic fractions of postmeiotic round spermatids where the protamine mRNAs are translationally silent, and is markedly reduced in elongated spermatids where the protamine mRNAs become activated for translation. surprisingly, the binding site for this activity maps to a region of the Prm-1 3' UTR not contained within the functional 62 nucleotides described above. In this report we show that the binding site for the 48/50-kDa protein can also delay translation of a reporter RNA in vivo, suggesting that the 48/50-kDa protein can repress the translation of Prm-1 mRNA during murine spermatogenesis. This observation proves that two separate regions of the Prm-1 3' UTR are sufficient to repress Prm-1 translation. In addition, immunocytochemistry and polysome analysis have revealed that this transgenic reporter mRNA fails to undergo proper translational activation. These results suggest that an additional region of the Prm-1 3' UTR is required for proper translational activation and that Prm-1 translational repression elements can be separated from those involved in translational activation. (C) 1997 Academic Press.