Plant Developmental Biology, Wageningen University and Research Centre, Droevendaalsesteeg 1, Wageningen 6708PB, The Netherlands.
Molecular Genetics, Department Biology, Utrecht University, Padualaan 8, Utrecht 3581CH, The Netherlands.
Nature. 2017 Aug 3;548(7665):97-102. doi: 10.1038/nature23317. Epub 2017 Jul 26.
During multicellular development, specification of distinct cell fates is often regulated by the same transcription factors operating differently in distinct cis-regulatory modules, either through different protein complexes, conformational modification of protein complexes, or combinations of both. Direct visualization of different transcription factor complex states guiding specific gene expression programs has been challenging. Here we use in vivo FRET-FLIM (Förster resonance energy transfer measured by fluorescence lifetime microscopy) to reveal spatial partitioning of protein interactions in relation to specification of cell fate. We show that, in Arabidopsis roots, three fully functional fluorescently tagged cell fate regulators establish cell-type-specific interactions at endogenous expression levels and can form higher order complexes. We reveal that cell-type-specific in vivo FRET-FLIM distributions reflect conformational changes of these complexes to differentially regulate target genes and specify distinct cell fates.
在多细胞发育过程中，不同细胞命运的特化通常是由不同顺式调控模块中以不同方式发挥作用的相同转录因子调节的，其作用方式可以是通过不同的蛋白质复合物、蛋白质复合物构象的改变，或两者的结合。直接观察指导特定基因表达程序的不同转录因子复合物状态一直具有挑战性。在这里，我们使用体内 FRET-FLIM（通过荧光寿命显微镜测量的Förster 共振能量转移）来揭示与细胞命运特化相关的蛋白质相互作用的空间分区。我们表明，在拟南芥根中，三种功能齐全的荧光标记细胞命运调节剂在其内源表达水平下建立细胞类型特异性相互作用，并能形成更高阶的复合物。我们揭示了细胞类型特异性的体内 FRET-FLIM 分布反映了这些复合物的构象变化，从而差异调节靶基因并特化不同的细胞命运。
