U2OS-CRISPR-SNAPf-SEH1 Cells

U2OS-CRISPR-SNAPf-SEH1 is a genome-edited human osteosarcoma cell line derived from U2OS cells in which the endogenous SEH1L (SEH1) gene has been modified using CRISPR/Cas9 technology to encode an in-frame SNAPf tag. SEH1 is a component of the Y-complex (also known as the NUP107-160 complex), a core structural module of the nuclear pore complex (NPC) that contributes to pore scaffold assembly and stability. By inserting the SNAPf coding sequence at the endogenous locus, the tagged SEH1 protein is expressed under native regulatory control, preserving physiological expression levels and minimizing perturbations to nuclear pore composition.

The SNAPf tag is an engineered, fast-reacting variant of the SNAP-tag that covalently binds benzylguanine-conjugated substrates, allowing selective and stable fluorescent labeling in live or fixed cells. In U2OS-CRISPR-SNAPf-SEH1 cells, the fusion protein localizes to the nuclear envelope in a punctate pattern characteristic of NPC distribution. Because labeling occurs at endogenous protein levels, this system is well suited for quantitative fluorescence microscopy, super-resolution imaging, and single-particle tracking analyses aimed at dissecting NPC organization and stoichiometry. The flat morphology and large nuclei of U2OS cells further facilitate high-resolution visualization of nuclear envelope structures.

SEH1 participates in NPC biogenesis and has also been implicated in kinetochore-associated processes during mitosis. Accordingly, this cell line provides a robust platform for investigating cell cycle-dependent NPC assembly and disassembly, spatial organization of the Y-complex within the pore scaffold, and potential dual roles of SEH1 at the nuclear envelope and mitotic kinetochores. U2OS-CRISPR-SNAPf-SEH1 enables mechanistic studies of nuclear pore architecture and dynamics under physiologically relevant expression conditions.