Over-expression of insulin-response element binding protein-1 (IRE-BP1) in mouse pancreatic islets increases expression of RACK1 and TCTP: Beta cell markers of high glucose sensitivity.
Over-expression of insulin-response element binding protein-1 (IRE-BP1) in mouse pancreatic islets increases expression of RACK1 and TCTP: Beta cell markers of high glucose sensitivity.
复制标题
DOI：
10.1016/j.bbapap.2016.10.015
复制
发表时间：
2017-02
期刊：
影响因子：
--
通讯作者：
Merchant ML
中科院分区：
文献类型：
--
作者：
Villafuerte BC;Barati MT;Rane MJ;Isaacs S;Li M;Wilkey DW;Merchant ML
针对胰岛素生长因子-1受体，通过胰岛素受体底物受体/PI-3激酶/Akt通路，对胰岛素反应元件结合蛋白-1 （IRE-BP1）的50kDa c端片段进行了靶向分析。50kDa c端IRE-BP1片段过表达对胰岛β细胞蛋白丰度的更广泛影响尚未确定。液相色谱-串联质谱（LC-MS/MS）分析了从背景菌株动物和转基因动物分离的胰岛细胞的重复裂解物，在胰岛β细胞中过表达IRE-BP1，结果显示，参与蛋白质合成、内质网（ER）应激和蛋白激酶C信号重要的支架蛋白的表达显著增加；部分经免疫印迹分析证实。对蛋白质表达网络模式的生物信息学分析表明，IRE-BP1过表达导致的蛋白质表达模式表明，用于蛋白质翻译后修饰、蛋白质折叠和蛋白质合成的功能性蛋白质网络被激活。共免疫沉淀实验证明了活化蛋白激酶C （RACK1）和翻译控制肿瘤蛋白（TCTP）两种差异调节蛋白受体之间的一种新的相互作用。胰岛β细胞中IRE-BP1过表达的蛋白质组学分析表明，IRE-BP1 (a)直接或间接通过建立高血糖导致核糖体蛋白和内质网应激标志物的表达增加，(b)导致RACK1和TCTP的增强和以前未描述的相互作用。本研究发现IRE-BP1的c端50kDa结构域过表达导致内质网应激标记物增加以及支架蛋白RACK1和TCTP之间新的相互作用。
A targeted analysis of the 50kDa C-terminal fragment of insulin-response element binding protein-1 (IRE-BP1) activation of insulin activation of target genes through the insulin receptor substrate receptor/PI-3 kinase/Akt pathway has been demonstrated for the insulin growth factor-1 receptor. The broader effects of 50kDa C-terminal IRE-BP1 fragment over-expression on protein abundance in pancreatic islet beta cells have not been determined. Liquid-chromatography coupled to tandem mass spectrometry (LC-MS/MS) analyses of replicate lysates of pancreatic islets isolated from background strain animals and transgenic animals, overexpressing IRE-BP1 in pancreatic islet beta cells, demonstrated statistically significant increases in the expression of proteins involved in protein synthesis, endoplasmic reticulum (ER) stress and scaffolding proteins important for protein kinase C signaling; some of which were confirmed by immunoblot analyses. Bioinformatic analysis of protein expression network patterns suggested IRE-BP1 over-expression leads to protein expression patterns indicative of activation of functional protein networks utilized for protein post-translational modification, protein folding, and protein synthesis. Co-immunoprecipitation experiments demonstrate a novel interaction between two differentially regulated proteins receptor for activated protein kinase C (RACK1) and translationally controlled tumor protein (TCTP). Proteomic analysis of IRE-BP1 over-expression in pancreatic islet beta cells suggest IRE-BP1 (a) directly or indirectly through establishing hyperglycemia results in increased expression of ribosomal proteins and markers of ER stress and (b) leads to the enhanced and previously un-described interaction of RACK1 and TCTP. This study identified C-terminal 50kDa domain of IRE-BP1 over-expression results in increased markers of ER-stress and a novel interaction between the scaffolding proteins RACK1 and TCTP.