Department of Medical Biochemistry and Molecular Biology, University of Greifswald, Greifswald, Germany.
Horm Metab Res. 2011 Mar;43(3):165-70. doi: 10.1055/s-0030-1270526. Epub 2011 Feb 1.
Glucose-dependent activation of the homeodomain transcription factor PDX-1 leads to its phosphorylation, to an increase in DNA binding capacity, and to NLS dependent translocation into the nucleus. To uncover unknown mediators of PDX-1 activation, PDX-1 interacting proteins were analysed by pull-down from (32)P-labelled, glucose-stimulated MIN6 cells. Recovered proteins were analysed by 2D gel electrophoresis and mass spectrometry. We identified 14-3-3ε as a novel PDX-1 binding protein and confirmed the interaction in vivo by Fluorescence Resonance Energy Transfer (FRET) analysis. We propose that 14-3-3ε interacts directly with PDX-1 to regulate its cellular distribution in pancreatic beta cells.
葡萄糖依赖性的同源域转录因子 PDX-1 的激活导致其磷酸化、DNA 结合能力增加，并通过核定位信号（NLS）依赖性转位进入细胞核。为了揭示 PDX-1 激活的未知介质，通过从（32）P 标记的、葡萄糖刺激的 MIN6 细胞中进行下拉实验，分析了与 PDX-1 相互作用的蛋白质。通过二维凝胶电泳和质谱分析回收的蛋白质。我们鉴定出 14-3-3ε 是一种新型的 PDX-1 结合蛋白，并通过荧光共振能量转移（FRET）分析在体内证实了这种相互作用。我们提出 14-3-3ε 与 PDX-1 直接相互作用，以调节其在胰岛β细胞中的细胞分布。
