Pumilio response and AU-rich elements drive rapid decay of Pnrc2-regulated cyclic gene transcripts.
Pumilio response and AU-rich elements drive rapid decay of Pnrc2-regulated cyclic gene transcripts.
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Pumilio 反应和富含 AU 的元件驱动 Pnrc2 调节的循环基因转录本的快速衰减。
DOI：
10.1016/j.ydbio.2020.03.017
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发表时间：
2020
影响因子：
2.7
通讯作者：
Amacher,SharonL
中科院分区：
文献类型：
--
作者：
Tietz,KielT;Gallagher,ThomasL;Mannings,MonicaC;Morrow,ZacharyT;Derr,NicolasL;Amacher,SharonL
脊椎动物的分节由分节时钟调节，分节时钟是控制体节或胚胎节周期性形成的生物振荡器，体节或胚胎节产生许多中胚层组织类型。这种分子振荡器产生周期性基因表达，其周期性与体节前中胚层（PSM）中的体节形成相同，PSM是产生成熟体节的间充质细胞区域。生物钟的分子组成部分包括编码转录抑制因子的基因家族，以及其他的基因周期。循环基因转录本被迅速清除，清除依赖于pnrc2（富含脯氨酸的核受体辅激活因子2）基因，该基因编码mRNA衰变衔接子。以前，我们发现her13 ′UTR以Pnrc2依赖的方式赋予稳定的转录本不稳定性，然而，清除环状基因转录本的分子机制在很大程度上仍然未知。为了鉴定对Pnrc2介导的衰变至关重要的her13 ′UTR的特征，我们开发了一系列携带3′UTR不同区域的转基因诱导型报告细胞系。我们发现her13 ′UTR的末端179个核苷酸（nts）是赋予快速不稳定性的必要和足够的。此外，我们发现另一个环状基因deltaC（dlc）的3′UTR也赋予Pnrc2依赖性不稳定性。模体分析表明，her1和dlc3 ′ UTR均含有位于末端的Pumilio反应元件（PRE）和富含AU的元件（战神），并且her13 ′UTR最后179 nt的PRE和ARE驱动报告基因mRNA的快速更新。最后，我们发现，Pnrc2残基和结构域的突变，已知促进人类PNRC2与衰变因子DCP1A和UPF1的相互作用，降低Pnrc2的能力，恢复正常的循环基因表达inpnrc2突变胚胎。我们的研究结果表明，Pnrc2与衰变机制的组件，并与Pumilio（Pum）蛋白和ARE结合蛋白，促进快速周转周期基因转录体在体节发生。
Vertebrate segmentation is regulated by the segmentation clock, a biological oscillator that controls periodic formation of somites, or embryonic segments, which give rise to many mesodermal tissue types. This molecular oscillator generates cyclic gene expression with the same periodicity as somite formation in the presomitic mesoderm (PSM), an area of mesenchymal cells that give rise to mature somites. Molecular components of the clock include theHes/herfamily of genes that encode transcriptional repressors, but additional genes cycle. Cyclic gene transcripts are cleared rapidly, and clearance depends upon thepnrc2(proline-rich nuclear receptor co-activator 2) gene that encodes an mRNA decay adaptor. Previously, we showed that theher13′UTR confers instability to otherwise stable transcripts in a Pnrc2-dependent manner, however, the molecular mechanism(s) by which cyclic gene transcripts are cleared remained largely unknown. To identify features of theher13′UTR that are critical for Pnrc2-mediated decay, we developed an array of transgenic inducible reporter lines carrying different regions of the 3′UTR. We find that the terminal 179 nucleotides (nts) of theher13′UTR are necessary and sufficient to confer rapid instability. Additionally, we show that the 3′UTR of another cyclic gene,deltaC (dlc), also confers Pnrc2-dependent instability. Motif analysis reveals that bothher1anddlc3′UTRs contain terminally-located Pumilio response elements (PREs) and AU-rich elements (AREs), and we show that the PRE and ARE in the last 179 nts of theher13′UTR drive rapid turnover of reporter mRNA. Finally, we show that mutation of Pnrc2 residues and domains that are known to facilitate interaction of human PNRC2 with decay factors DCP1A and UPF1 reduce the ability of Pnrc2 to restore normal cyclic gene expression inpnrc2mutant embryos. Our findings suggest that Pnrc2 interacts with decay machinery components and cooperates with Pumilio (Pum) proteins and ARE-binding proteins to promote rapid turnover of cyclic gene transcripts during somitogenesis.