CPSF6 is a component of the CFIm complex, involved in mRNA 3′end processing. Despite increasing interest on this protein as a consequence of proposed roles in cancer and HIV infection, several aspects of CPSF6 biological function are poorly understood. In this work we studied the expression of the zebrafish ortholog cpsf6 in early stages of embryo development. Quantitative RT-PCR studies showed that zebrafish cpsf6 mRNA is maternally inherited and that its concentration markedly decreases during early development. We found a generalized distribution of cpsf6 mRNA in early stages through whole mount hybridization experiments. By performing Western blot, we also found a decrease in zebrafish Cpsf6 levels during development. Our analysis of the subcellular localization of this protein using a heterologous system showed a distinct pattern characterized by the presence of nuclear foci. We also studied the relevance of different protein domains on subcellular localization, showing that the C-terminal domain is critical for nuclear localization. Collectively, our results showed that cpsf6 expression changes during early development and that the subcellular localization of the protein is similar to that of the human ortholog.

CPSF6是CFIm复合体的一个成分，参与mRNA 3'末端加工。尽管由于提议的在癌症和HIV感染中的作用而对该蛋白越来越感兴趣，但对CPSF6生物学功能的几个方面知之甚少。在这项工作中，我们研究了斑马鱼直系同源蛋白cpsf6在胚胎发育早期的表达。定量RT-PCR研究表明，斑马鱼cpsf6 mRNA是母体遗传的，其浓度在早期发育过程中明显降低。我们发现了cpsf6的广义分布在整个装配杂交实验的早期阶段就可以检测到mRNA。通过进行蛋白质印迹，我们还发现在发育过程中斑马鱼Cpsf6水平降低。我们使用异源系统对该蛋白的亚细胞定位进行的分析显示出以核病灶的存在为特征的独特模式。我们还研究了不同蛋白结构域对亚细胞定位的相关性，表明C末端结构域对于核定位至关重要。总的来说，我们的结果表明cpsf6的表达在早期发育过程中发生了变化，并且该蛋白的亚细胞定位与人类直系同源物相似。