hnRNPDL Phase Separation Is Regulated by Alternative Splicing and Disease-Causing Mutations Accelerate Its Aggregation
hnRNPDL Phase Separation Is Regulated by Alternative Splicing and Disease-Causing Mutations Accelerate Its Aggregation
复制标题
DOI：
10.1016/j.celrep.2019.12.080
复制
发表时间：
2020-01-28
期刊：
影响因子：
8.8
通讯作者：
Ventura, Salvador
中科院分区：
文献类型：
--
作者：
Batlle, Cristina;Yang, Peiguo;Ventura, Salvador
朊病毒样蛋白形成多价组装体，并相分离成无膜细胞器。异质性核糖核蛋白D样（hnRNPDL）是一种RNA加工朊病毒样蛋白，具有三种选择性剪接（AS）异构体，其两个无序结构域中的一个或全部缺失。有人认为AS可能通过控制异构体中多价无序区的掺入来调节RNA加工蛋白的组装特性。这反过来又会调节它们在下游剪接程序中的活性。在这里，我们证明，AS控制hnRNPDL的相分离，以及其核复合物的大小和动力学，其核质穿梭，和淀粉样变性。hnRNPDL的C端朊病毒样结构域中高度保守的D378突变导致肢带型肌营养不良症1G。我们发现D378 H/N疾病突变影响hnRNPDL组装特性，加速聚集并显着降低果蝇肌肉中的蛋白质溶解度，这表明这种肌肉疾病的遗传功能丧失机制。
Prion-like proteins form multivalent assemblies and phase separate into membraneless organelles. Heterogeneous ribonucleoprotein D-like (hnRNPDL) is a RNA-processing prion-like protein with three alternative splicing (AS) isoforms, which lack none, one, or both of its two disordered domains. It has been suggested that AS might regulate the assembly properties of RNA-processing proteins by controlling the incorporation of multivalent disordered regions in the isoforms. This, in turn, would modulate their activity in the downstream splicing program. Here, we demonstrate that AS controls the phase separation of hnRNPDL, as well as the size and dynamics of its nuclear complexes, its nucleus-cytoplasm shuttling, and amyloidogenicity. Mutation of the highly conserved D378 in the disordered C-terminal prion-like domain of hnRNPDL causes limb-girdle muscular dystrophy 1G. We show that D378H/N disease mutations impact hnRNPDL assembly properties, accelerating aggregation and dramatically reducing the protein solubility in the muscle of Drosophila, suggesting a genetic loss-of-function mechanism for this muscular disorder.