Measuring Protein Nuclear Transport via a Dual Reporter in iPSC-Derived Neurons

Nucleocytoplasmic transport (NCT) plays a critical role in maintaining cellular homeostasis, and its dysregulation has been shown to be implicated in many neurological diseases. To identify NCT deficits and determine the pathogenesis underlying the impaired NCT-related diseases, it is extremely important to develop reliable approaches to measure the cellular NCT activities, including protein import and export activities. Here, we present a method to measure nuclear transport for protein cargos in cultured cells. A lentiviral vector contains a dual reporter system expressing green fluorescent protein fused with nuclear export sequence, and red fluorescent protein fused with nuclear localization sequence was employed to infect a variety of cultured cells, including human induced pluripotent stem cells-derived neurons. The nuclear and cytoplasmic signal density of reporters were measured using ImageJ software, and thus the protein export and import activities were evaluated at a single-cell level.