The ATP2B4 knockout HEK293T polyclonal cells are a pooled population of human embryonic kidney cells genetically modified by CRISPR/Cas9-mediated disruption of the ATP2B4 gene. This product provides a polyclonal knockout model, without single-cell cloning, enabling loss-of-function studies of the plasma membrane calcium ATPase 4 (PMCA4) in a robust, transfectable epithelial background.
The parental HEK293T cell line is derived from human embryonic kidney tissues, immortalized by adenovirus 5 DNA and constitutively expressing the SV40 large T antigen. These adherent epithelial cells are widely employed for high-efficiency transfection, protein overexpression, and viral packaging. The SV40 T antigen permits episomal replication of plasmids containing the SV40 origin, enhancing recombinant protein yield and making this a versatile host for studying membrane transporters and signaling proteins.
ATP2B4 encodes PMCA4, a high-affinity calcium efflux pump that maintains low resting cytosolic calcium by extruding Ca2? across the plasma membrane. Its activity is tightly regulated by calmodulin (CALM1), protein kinase A (PKA), acidic phospholipids, and calcium/calmodulin-dependent kinase II (CaMKII). Upon calcium binding, calmodulin binds to the autoinhibitory domain of PMCA4, relieving autoinhibition and increasing pump activity. PMCA4 also interacts with PDZ domain-containing scaffolds such as NHERF1/EBP50, PSD-95, and Homer1, which spatially organize the pump within signaling microdomains. Downstream, PMCA4-mediated calcium extrusion modulates the activity of CaMKII, calcineurin, nitric oxide synthase, and transcription factors including NFAT, positioning the pump as a key regulator of calcium-dependent transcriptional programs and second messenger cascades.
In the HEK293T context, disrupting ATP2B4 likely impairs calcium clearance, leading to elevated basal cytosolic calcium and altered kinetics of calcium transients following receptor activation. This dysregulation can perturb the balance of calcium-sensitive effectors such as CaMKII and calcineurin, potentially affecting gene expression, proliferation, and apoptosis. Because HEK293T cells express endogenous G protein-coupled receptors and receptor tyrosine kinases, this knockout model is particularly suited for dissecting how impaired calcium efflux remodels signaling downstream of phospholipase C and IP3 receptor pathways.
This product is applicable to diverse experimental paradigms including intracellular calcium imaging with Fluo-4 AM, flow cytometric calcium flux assays, and phospho-signaling analysis of downstream effectors like CaMKII and NFAT. It also supports functional complementation studies, co-immunoprecipitation of ATP2B4-interacting partners, and screening of compounds targeting calcium homeostasis. Researchers investigating the molecular basis of malaria resistance, neurodegeneration, or sensorineural hearing loss will find these cells valuable for bridging in vitro phenotypes with disease mechanisms. For additional technical specifications or custom inquiries, please contact Ascent Research.
