BPNT1 Knockout HEK293T Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal population of HEK293T cells harboring a targeted disruption of the BPNT1 gene. This model eliminates the activity of 3′(2′),5′-bisphosphate nucleotidase 1, the enzyme responsible for dephosphorylating 3′-phosphoadenosine 5′-phosphate (PAP) and 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to AMP, thereby disrupting a critical regulatory node in the PAPS cycle and sulfation pathways.
The parental HEK293T cell line, derived from human embryonic kidney cells transformed with adenovirus type 5 DNA, stably expresses the SV40 large T antigen, facilitating episomal replication of plasmids and supporting high-efficiency transfection. These cells are extensively employed for recombinant protein expression, lentiviral production, and CRISPR-based genome editing, and they retain endogenous expression of sulfate transporters, sulfotransferases, and lithium-sensitive signaling components, making them a relevant host for BPNT1 functional studies.
BPNT1 functions as a magnesium-dependent phosphatase that hydrolyzes PAP and PAPS, thus relieving product inhibition of cytosolic sulfotransferases (SULTs) and maintaining cellular sulfate assimilation. The enzyme is competitively inhibited by lithium ions, connecting its activity to the therapeutic mechanism of lithium in bipolar disorder. BPNT1 operates downstream of PAPS synthases (PAPSS1/2) and sulfate import via SLC26 transporters; its loss causes PAP accumulation, which feedback-inhibits SULTs and impairs sulfation of hormones, neurotransmitters, and proteoglycans. Concurrently, AMP-dependent signaling and lithium-sensitive inositol monophosphatase (IMPase) activity are altered, reshaping the cellular response to lithium.
In the HEK293T background, BPNT1 knockout recapitulates pathological PAP accumulation observed in sulfation-related disorders, enabling quantitative assessment of PAP levels by LC-MS, sulfotransferase activity assays, and metabolite profiling. The cells’ inherent lithium sensitivity permits dose-response cytotoxicity studies, while the disruption of sulfation pathways provides a platform for investigating the molecular basis of lithium-responsive bipolar disorder and developmental defects tied to impaired sulfur metabolism.
These polyclonal knockout cells are suitable for functional genomics screens to identify modulators of the PAP-sulfation axis, lithium pharmacogenomics studies, and drug metabolism research focusing on sulfated compounds. High-throughput screening for PAP pathway modulators can employ PAP quantification, sulfotransferase activity, lithium sensitivity cytotoxicity, and RNA-seq readouts. The model also supports detailed mechanistic studies of bipolar disorder signaling networks. For ordering and technical support, please contact Ascent Research.
