DNA聚合酶δ结合蛋白38是microRNA-291a-5p的一个靶基因

DNA polymerase delta-interacting protein 38 is a target gene of microRNA-291a-5p

摘要:

DNA聚合酶δ结合蛋白38 (DNA Polymerase delta-interacting protein 38，PDIP38) 是2003年新鉴定的一个基因，目前认为其可能在DNA修复、有丝分裂以及血管平滑肌细胞迁移中起重要作用。根据本实验室前期在胚胎干细胞中对该基因的研究，认为microRNA可能在PDIP38的调控过程中发挥了重要作用。为证实这种推论，运用生物信息学方法预测发现在胚胎干细胞中高表达的microRNA——microRNA-291a-5p (miR-291a-5p) 与PDIP38的开放阅读框 (ORF) 有一个配对非常理想的靶位点，通过构建该靶位点的报告基因载体以及ORF表达载体，分别进行荧光素酶报告基因分析以及细胞转染和Western blotting方法。结果证明miR-291a-5p能够直接调节PDIP38的蛋白表达。进一步运用real-time PCR和Western blotting分析证明了在胚胎干细胞中miR-291a-5p能够调节内源PDIP38的蛋白表达而对其mRNA表达无影响，这些都证明PDIP38确实是miR-291a-5p的一个靶基因。

Abstract:

DNA polymerase delta-interacting protein 38 (PDIP38) was identified in 2003 as a human DNA polymerase delta interacting protein which plays important roles in DNA repair, mitosis and vascular smooth muscle cells (VSMCs) migration. Our previous study showed that PDIP38 was expressed in mouse embryonic stem (ES) cells and upregulated in protein levels after differentiation from ES cells, while the expression in mRNA levels was not changed. We supposed that microRNA played key roles in the regulation of PDIP38 and the differentiation of ES cells. By bioinformatics assay, we predicted that PDIP38 was a potential target of microRNA-291a-5p (miR-291a-5p). Futhermore, we validated the possibility of miR-291a-5p to regulate the protein expression of PDIP38. Using luciferase reporter assay, realtime PCR and western blot methods, we firstly demonstrated that miR-291a-5p directly inhibited the expression of PDIP38. The present results shed a new light on the study of PDIP38 and miR-291a-5p in the differentiation of ES cells.