Eliscovich Carolina, Peset Isabel, Vernos Isabelle, Méndez Raúl
Centre for Genomic Regulation (CRG), C/ Dr. Aiguader, 88, 08003 Barcelona, Spain.
Nat Cell Biol. 2008 Jul;10(7):858-65. doi: 10.1038/ncb1746. Epub 2008 Jun 8.
Meiotic progression requires the translational activation of stored maternal mRNAs, such as those encoding cyclin B1 or mos. The translation of these mRNAs is regulated by the cytoplasmic polyadenylation element (CPE) present in their 3'UTRs, which recruits the CPE-binding protein CPEB. This RNA-binding protein not only dictates the timing and extent of translational activation by cytoplasmic polyadenylation but also participates, together with the translational repressor Maskin, in the transport and localization, in a quiescent state, of its targets to subcellular locations where their translation will take place. During the early development of Xenopus laevis, CPEB localizes at the animal pole of oocytes and later on at embryonic spindles and centrosomes. Disruption of embryonic CPEB-mediated translational regulation results in abnormalities in the mitotic apparatus and inhibits embryonic mitosis. Here we show that spindle-localized translational activation of CPE-regulated mRNAs, encoding for proteins with a known function in spindle assembly and chromosome segregation, is essential for completion of the first meiotic division and for chromosome segregation in Xenopus oocytes.
减数分裂进程需要激活储存的母源mRNA的翻译，例如那些编码细胞周期蛋白B1或mos的mRNA。这些mRNA的翻译受其3'UTR中存在的细胞质聚腺苷酸化元件（CPE）调控，该元件招募CPE结合蛋白CPEB。这种RNA结合蛋白不仅通过细胞质聚腺苷酸化决定翻译激活的时间和程度，还与翻译抑制因子Maskin一起，将其处于静止状态的靶标运输并定位到其翻译将发生的亚细胞位置。在非洲爪蟾的早期发育过程中，CPEB定位于卵母细胞的动物极，随后定位于胚胎纺锤体和中心体。胚胎CPEB介导的翻译调控的破坏会导致有丝分裂装置异常并抑制胚胎有丝分裂。在这里，我们表明，纺锤体定位的CPE调控mRNA的翻译激活，这些mRNA编码在纺锤体组装和染色体分离中具有已知功能的蛋白质，对于非洲爪蟾卵母细胞第一次减数分裂的完成和染色体分离至关重要。
