The KCNJ2 knockout HT29 polyclonal cells are a CRISPR/Cas9-edited polyclonal population targeting the KCNJ2 gene in the HT29 colorectal adenocarcinoma cell line. This polyclonal pool contains a spectrum of genome-edited cells, avoiding clonal selection and enabling loss-of-function analysis of the Kir2.1 inward rectifier potassium channel. CRISPR/Cas9-mediated gene disruption abrogates functional channel expression, and researchers should independently confirm knockout efficiency using molecular and functional assays.
HT29 cells, derived from a 44-year-old female primary colorectal adenocarcinoma, serve as an intestinal epithelial model with characterized absorptive and barrier properties. These cells form polarized monolayers with tight junctions, facilitating studies of epithelial transport, drug permeability, and colorectal cancer biology. Their utility in knockout experiments provides a physiologically relevant background for interrogating ion channel functions in gut epithelium.
The KCNJ2 gene product, Kir2.1, is a strong inward rectifier potassium channel critical for setting the resting membrane potential and controlling potassium homeostasis. Kir2.1 is activated by PIP2 and inhibited by Gq-coupled receptor signaling (e.g., muscarinic M1 receptor) through PLC??-mediated PIP2 depletion. Protein kinases PKA and PKC phosphorylate and modulate the channel. Kir2.1 interacts with SAP97 (DLG1), syntrophin, and the dystrophin-associated protein complex for proper localization. Downstream effects of Kir2.1 activity include regulation of potassium flux, membrane potential, epithelial ion transport, and cell volume.
In HT29 cells, KCNJ2 knockout eliminates inward rectifier potassium currents, depolarizes the membrane, and disrupts electrochemical gradients essential for vectorial ion transport and barrier function. This perturbation likely affects absorptive processes and volume regulation, and may influence colorectal cancer phenotypes such as proliferation and migration. The model thus offers a platform to explore the contribution of Kir2.1 to epithelial pathophysiology and its potential as a therapeutic target in colorectal adenocarcinoma.
Applications include patch clamp electrophysiology to verify channel loss, western blotting and immunofluorescence for protein expression, potassium flux measurements, and TEER assays to evaluate epithelial integrity. Cell proliferation and migration assays can reveal functional consequences, while the system supports screening for potassium channel modulators or studying channelopathy mechanisms. This knockout cell pool enables integrated investigations of Kir2.1 in colorectal epithelial biology. For additional details, please contact Ascent Research.
