PKM Knockout HK-2 Cell Line

The PKM Knockout HK-2 Cell Line is a CRISPR/Cas9-edited knockout cell line in which the human PKM gene has been disrupted to create a defined loss-of-function model. This stable system enables precise investigation of pyruvate kinase M (PKM) functions in glycolysis, metabolic reprogramming, and signal transduction within a renal proximal tubular epithelial context, avoiding the limitations of transient knockdown approaches.

HK-2 cells are an immortalized human kidney proximal tubular epithelial line derived from normal adult tissue. They retain critical features of polarized epithelia, including brush border enzyme expression and vectorial transport activities, making them a widely accepted model for studying renal reabsorption, secretion, drug transport, and nephrotoxicity. Their physiological relevance supports robust in vitro analysis of metabolic and toxicological processes.

PKM encodes pyruvate kinase, the enzyme that catalyzes the rate-limiting final step of glycolysis, converting phosphoenolpyruvate to pyruvate. The PKM2 isoform also functions as a transcriptional coactivator and protein kinase. PKM expression and activity are regulated by upstream signals such as EGFR, FGFR1, MYC, HIF1A, mTORC1, insulin, and hypoxia. It interacts with HIF1A, ??-catenin, STAT3, integrin ??v??3, and LDHA, and sits at the nexus of glycolysis, pentose phosphate, mTOR, and AMPK pathways. Downstream, PKM promotes lactate production, nucleotide biosynthesis, and transcription of proliferation genes including CCND1, MYC, and SLC2A1, while suppressing apoptosis. Knockout of PKM in HK-2 cells eliminates pyruvate kinase activity, impairing glycolytic ATP and pyruvate output and likely triggering a metabolic shift toward oxidative phosphorylation or glutaminolysis, with consequential effects on cell proliferation and stress responses.

In the kidney proximal tubule, glycolytic flux is closely tied to reabsorptive energy demands and cellular homeostasis. PKM disruption in HK-2 cells therefore provides a powerful model to interrogate metabolic vulnerabilities associated with diabetic nephropathy, acute kidney injury, and renal cell carcinoma, where PKM2 upregulation and Warburg-like remodeling are often observed. This knockout system helps elucidate how loss of the glycolytic endpoint impacts tubular epithelial viability, transport capacity, and injury repair mechanisms.

This cell line is suited for a range of applications, including measurement of extracellular acidification rate (ECAR) and oxygen consumption to profile metabolic switching, lactate and glucose consumption assays, ATP quantification, cell proliferation and apoptosis studies, drug toxicity screening, and metabolomic or transcriptomic analyses. The model also enables isoform-specific rescue experiments and investigation of PKM2?dependent transcriptional regulation via RT-qPCR or chromatin immunoprecipitation. For detailed technical specifications or custom inquiries, please contact Ascent Research.