The CBR4 Knockout K-562 Polyclonal Cells represent a polyclonal population of K-562 cells engineered via CRISPR/Cas9-mediated disruption of the CBR4 gene. This heterogeneous knockout pool, generated without single-cell cloning, provides a robust loss-of-function model for studying the role of CBR4??a mitochondrial carbonyl reductase??in human cells.
The parental K-562 cell line is a well-established human chronic myeloid leukemia (CML) model, derived from the pleural effusion of a 53-year-old female in blast crisis. K-562 cells grow in suspension and exhibit lymphoblastoid morphology. They are widely utilized for hematopoietic differentiation studies and as a platform for investigating oncogenic signaling and metabolic reprogramming in leukemia.
CBR4 functions as a key enzyme in the biosynthesis of coenzyme Q10 (ubiquinone), an essential lipid-soluble electron carrier in the mitochondrial respiratory chain. Its carbonyl reductase activity is critical for the hydroxylation required in CoQ10 production. CBR4 is transcriptionally regulated by PPARGC1A (PGC-1??) and other mitochondrial biogenesis signals. It interacts directly with COQ3, COQ5, COQ7, and COQ9, forming part of the CoQ biosynthetic complex. Downstream, CBR4 activity ensures proper coenzyme Q10 levels, which support electron transport chain complexes I, II, and III, and maintain the mitochondrial membrane potential. Disruption of CBR4 therefore abolishes carbonyl reductase function, leading to deficient CoQ10 synthesis, impaired electron transport chain activity, and reduced mitochondrial ATP production.
In the K-562 cellular context, CBR4 knockout creates a relevant model for dissecting mitochondrial dysfunction within a leukemic background. K-562 cells exhibit high glycolytic flux but also retain active oxidative phosphorylation, making them sensitive to perturbations in the ubiquinone biosynthesis pathway. The loss of CBR4 leads to CoQ10 deficiency, which compromises electron transfer and ATP generation, mimicking features of human mitochondrial encephalopathies and primary CoQ10 deficiency syndromes. This model enables investigation into the interplay between mitochondrial metabolism and leukemia cell survival, proliferation, and differentiation.
Researchers can apply this knockout model to a broad range of experimental scenarios, including modeling coenzyme Q10 deficiency, screening small-molecule correctors for mitochondrial disorders, and dissecting metabolic pathways. Representative assays include Western blotting and RT-qPCR to confirm CBR4 disruption, liquid chromatography?Ctandem mass spectrometry (LC-MS/MS) for quantifying cellular CoQ10 levels, mitochondrial ATP assays, oxygen consumption rate (OCR) measurements, JC-1 staining for mitochondrial membrane potential, and cell viability tests under galactose-based mitochondrial stress conditions. For additional information and technical support, please contact Ascent Research.
