miR-375 targets 3'-phosphoinositide-dependent protein kinase-1 and regulates glucose-induced biological responses in pancreatic beta-cells.
miR-375 targets 3'-phosphoinositide-dependent protein kinase-1 and regulates glucose-induced biological responses in pancreatic beta-cells.
复制标题
DOI：
10.2337/db07-1614
复制
发表时间：
2008-10
期刊：
影响因子：
7.7
通讯作者：
van Obberghen E
中科院分区：
文献类型：
--
作者：
El Ouaamari A;Baroukh N;Martens GA;Lebrun P;Pipeleers D;van Obberghen E
微RNA是短的非编码RNA，调节基因表达。我们假设已知在β细胞生理学中重要的磷脂酰肌醇3-激酶（PI 3-激酶）级联可以由microRNA调节。在此，我们重点关注胰腺特异性miR-375作为其预测的靶点3 ′-磷酸肌醇依赖性蛋白激酶1（PDK 1）的潜在调节剂，并分析其在胰岛素产生细胞对葡萄糖水平升高的反应中的意义。研究设计和方法-我们使用胰岛素瘤-1E细胞，分析miR-375对PDK1蛋白水平和下游信号传导的影响，使用定量RT-PCR分析葡萄糖诱导的胰岛素基因表达，并通过测量胸苷掺入来分析DNA合成。此外，我们分析了葡萄糖对INS-1E细胞和原代大鼠胰岛中miR-375表达的影响。最后，在糖尿病Goto-Kakizaki（GK）大鼠中分析分离的胰岛中的miR-375表达。我们发现miR-375直接靶向PDK 1并降低其蛋白水平，导致对胰岛素基因表达和DNA合成的葡萄糖刺激作用降低。此外，葡萄糖导致miR-375前体水平降低和伴随的PDK1蛋白增加。重要的是，葡萄糖对miR-375表达的调节也发生在原代大鼠胰岛中。最后，发现miR-375表达在喂食的糖尿病GK大鼠胰岛中降低。结论-我们的研究结果为胰腺特异性微小RNA（miR-375）在调节PDK 1（胰腺β细胞PI 3激酶信号传导的关键分子）中的作用提供了证据。葡萄糖对miR-375的影响与miR-375参与葡萄糖调节胰岛素基因表达和β细胞生长的观点一致。
OBJECTIVE—MicroRNAs are short, noncoding RNAs that regulate gene expression. We hypothesized that the phosphatidylinositol 3-kinase (PI 3-kinase) cascade known to be important in β-cell physiology could be regulated by microRNAs. Here, we focused on the pancreas-specific miR-375 as a potential regulator of its predicted target 3′-phosphoinositide–dependent protein kinase-1 (PDK1), and we analyzed its implication in the response of insulin-producing cells to elevation of glucose levels. RESEARCH DESIGN AND METHODS—We used insulinoma-1E cells to analyze the effects of miR-375 on PDK1 protein level and downstream signaling using Western blotting, glucose-induced insulin gene expression using quantitative RT-PCR, and DNA synthesis by measuring thymidine incorporation. Moreover, we analyzed the effect of glucose on miR-375 expression in both INS-1E cells and primary rat islets. Finally, miR-375 expression in isolated islets was analyzed in diabetic Goto-Kakizaki (GK) rats. RESULTS—We found that miR-375 directly targets PDK1 and reduces its protein level, resulting in decreased glucose-stimulatory action on insulin gene expression and DNA synthesis. Furthermore, glucose leads to a decrease in miR-375 precursor level and a concomitant increase in PDK1 protein. Importantly, regulation of miR-375 expression by glucose occurs in primary rat islets as well. Finally, miR-375 expression was found to be decreased in fed diabetic GK rat islets. CONCLUSIONS—Our findings provide evidence for a role of a pancreatic-specific microRNA, miR-375, in the regulation of PDK1, a key molecule in PI 3-kinase signaling in pancreatic β-cells. The effects of glucose on miR-375 are compatible with the idea that miR-375 is involved in glucose regulation of insulin gene expression and β-cell growth.
登录
查看更多内容
影响因子：
64.8
作者：
Lu, J;Getz, G;Golub, TR
通讯作者：
Golub, TR
影响因子：
4.8
作者：
Lingohr, Melissa K.;Briaud, Isabelle;Rhodes, Christopher J.
通讯作者：
Rhodes, Christopher J.
影响因子：
15.9
作者：
Hoorens, A;VandeCasteele, M;Pipeleers, D
通讯作者：
Pipeleers, D
影响因子：
4.1
作者：
Bilanges, B;Stokoe, D
通讯作者：
Stokoe, D
影响因子：
6.4
作者：
Lee, Eun Jon;Gusev, Yuriy;Schmittgen, Thomas D.
通讯作者：
Schmittgen, Thomas D.