The KCNJ2 Knockout HAP1 Polyclonal Cells product provides a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 near-haploid human cell line, engineered to disrupt the endogenous KCNJ2 gene. This targeted gene disruption eliminates functional expression of the Kir2.1 inward rectifier potassium channel, offering a loss-of-function model to investigate KCNJ2-dependent signaling and electrophysiology. The polyclonal nature maintains genetic diversity within the population, avoiding reliance on any single clone while enabling robust functional genomics studies.
The HAP1 parent cell line is a fibroblast-like, near-haploid human cell line originally derived from the BCR-ABL-positive KBM-7 chronic myeloid leukemia line. Its near-haploid karyotype renders it uniquely suited for knockout and functional genomics screening because only a single allele requires disruption to achieve gene inactivation. HAP1 cells exhibit stable growth properties and are widely adopted in CRISPR-based loss-of-function screens, making them an ideal chassis for interrogating the consequences of KCNJ2 knockout in a tractable, scalable cellular context.
KCNJ2 encodes the Kir2.1 protein, a critical inward rectifier potassium channel responsible for the IK1 current that stabilizes the resting membrane potential in excitable cells such as cardiomyocytes, skeletal muscle, and neurons. Kir2.1 activity is tightly regulated by upstream factors including phosphatidylinositol 4,5-bisphosphate (PIP2), protein kinase A (PKA), protein kinase C (PKC), and Src family tyrosine kinases. The channel interacts with scaffolding proteins such as SAP97 (DLG1) and caveolin-3, as well as filamin A and 14-3-3 proteins, which influence its surface localization and function. Downstream, Kir2.1-mediated potassium influx directly impacts membrane potential, which in turn modulates L-type calcium channel (Cav1.2) activity and calcium/calmodulin-dependent protein kinase II (CaMKII) signaling, ultimately controlling gene expression programs linked to cellular excitability. Disruption of Kir2.1 thus ablates IK1 current, leading to membrane depolarization and altered excitability cascades.
Although HAP1 cells are not classically excitable, the KCNJ2 knockout in this near-haploid background provides a clean genetic system to dissect Kir2.1 channel biology, protein-protein interactions, and pharmacology without interference from wild-type alleles. This polyclonal knockout model recapitulates the loss of function observed in human channelopathies such as Andersen-Tawil syndrome (long QT syndrome 7), short QT syndrome, familial atrial fibrillation, and periodic paralysis. Researchers can leverage this model to explore how KCNJ2 disruption alters cellular signaling networks, including downstream calcium handling and transcriptional responses, thereby bridging basic molecular mechanisms to disease-relevant phenotypes.
This product is optimal for cardiac electrophysiology research, ion channel drug screening, and modeling potassium channelopathies. Typical applications include patch-clamp electrophysiology to confirm IK1 current loss, Western blotting and immunofluorescence to verify Kir2.1 protein absence and mislocalization, calcium imaging to assess downstream excitability changes, and co-immunoprecipitation studies with SAP97 to probe channel interactome alterations. RNA-seq transcriptomic analysis can uncover KCNJ2-dependent gene expression networks. For further information or custom requests, please contact Ascent Research.
