POM121 Knockout HK-2 Cell Line

The POM121 Knockout HK-2 Cell Line is a CRISPR/Cas9-edited knockout cell line engineered to disrupt the endogenous POM121 gene in immortalized human kidney proximal tubule epithelial HK-2 cells. This loss-of-function model is designed for advanced studies of nuclear pore complex (NPC) biology, nucleocytoplasmic transport, and associated cellular processes. The knockout product format is a stable cell line that enables reproducible investigation of POM121-dependent mechanisms without the need for transient suppression approaches. Researchers can employ this model to explore fundamental questions about NPC assembly and nuclear envelope organization in a physiologically relevant renal epithelial context.

The HK-2 host cell line is an extensively characterized model of the human kidney proximal tubule, immortalized through expression of HPV-16 E6/E7 oncoproteins. These cells retain differentiated functions of the proximal tubule epithelium, including the capacity for reabsorption of water, ions, and nutrients, as well as active secretion of organic anions and cations. HK-2 cells are widely used in nephrotoxicity screening, renal physiology assays, and studies of epithelial transport processes. The parental line provides a well-defined, karyotypically stable background that supports long-term culture and genetic manipulation, making it an ideal platform for generating targeted knockout derivatives.

POM121 encodes a transmembrane nucleoporin that plays an essential structural role in anchoring the NPC to the nuclear envelope. The protein functions as a scaffold for the NUP107-160 subcomplex and interacts directly with multiple nucleoporins including NUP155, NUP160, and NUP98, as well as with the nuclear lamina component lamin B. Upstream of its function, POM121 expression is regulated by the transcription factor SP1 and is phosphorylated by CDK1/cyclin B during mitosis, linking its activity to cell cycle progression. Downstream, POM121 is critical for NPC assembly and facilitates the nucleocytoplasmic transport of macromolecules mediated by transport receptors such as importin ?? and the small GTPase Ran. Disruption of POM121, therefore, compromises the integrity of the nuclear envelope and perturbs the bidirectional flow of proteins and RNA between the nucleus and cytoplasm.

In the HK-2 cellular context, knockout of POM121 introduces a powerful tool for dissecting how NPC dysfunction affects kidney epithelial homeostasis. Proximal tubule cells rely on precise trafficking of transcription factors, signaling molecules, and membrane transporters to maintain their reabsorptive and secretory functions. POM121 loss is expected to impair these processes by disrupting nuclear transport, potentially altering the expression and localization of critical renal transporters and stress response factors. This model thus allows researchers to connect molecular events at the nuclear pore to phenotypic outcomes in a cell type that is central to kidney physiology and susceptible to injury from nephrotoxic agents.

This POM121 knockout cell line supports a wide range of research applications. It can be used for high-resolution imaging of NPC structure via transmission electron microscopy and immunofluorescence, quantitative nuclear import assays using GFP-NLS reporters, and functional studies of nucleocytoplasmic trafficking by fluorescein methotrexate uptake measurements. Interaction proteomics approaches such as co-immunoprecipitation enable mapping of altered NPC interactomes. Transcriptomic analysis (RNA-seq) and cell viability assays provide insights into downstream consequences of POM121 loss. The model is particularly valuable for investigating mechanisms of viral infections that exploit the nuclear pore, delineating nucleoporin contributions to cancer cell biology, and assessing nephrotoxicity pathways. For additional details or technical support, please contact Ascent Research.