The HOMER2 Knockout Jurkat Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population engineered for loss-of-function studies of the HOMER2 gene in a human T lymphocyte background. This product is generated by introducing CRISPR/Cas9-mediated gene disruption into the HOMER2 locus, yielding a heterogeneous pool of edited Jurkat cells suitable for interrogating the scaffolding functions of HOMER2 in T cell receptor (TCR) signaling. The polyclonal format eliminates the clonal selection bias inherent in monoclonal lines, providing a more physiologically representative population for downstream analyses.
The Jurkat host cell line is an immortalized CD4+ T lymphocyte line derived from acute T cell leukemia. Jurkat cells are widely used for their robust TCR signaling, which drives calcium influx and transcriptional activation. They express TCR/CD3 components and CD28, providing an ideal platform for studying early T cell activation and leukemogenic signaling. Suspension-adapted growth and well-characterized signaling facilitate calcium imaging, reporter assays, and functional genomics.
HOMER2 encodes a scaffolding protein that coordinates TCR signal transduction by coupling proximal tyrosine kinase cascades to calcium mobilization and NFAT-dependent transcription. Upon TCR engagement, the Src family kinase Lck phosphorylates ITAMs in the CD3 chains, leading to ZAP-70 recruitment and activation of LAT and PLC??1. HOMER2 physically interacts with PLC??1, calcineurin, and NFAT, and tethers PLC??1 to IP3 receptors (IP3R) and TRPC channels on the endoplasmic reticulum. This spatial organization enhances IP3-mediated calcium release from intracellular stores and promotes sustained calcium influx, which is essential for calcineurin-mediated dephosphorylation of NFAT. Dephosphorylated NFAT translocates to the nucleus to drive transcription of IL-2 and other activation genes.
In the Jurkat T cell context, HOMER2 disruption impairs coupling of TCR signals to calcium oscillations and NFAT activation, offering a model to dissect this scaffold-dependent amplification. Because Jurkat cells exhibit high basal NFAT activity and sensitivity to calcium modulators, this polyclonal knockout population enables precise dissection of HOMER2’s role in tuning TCR response dynamics. The model is particularly valuable for exploring immune signaling and leukemia biology, given the derivation of Jurkat cells from T cell acute lymphoblastic leukemia (T-ALL). HOMER2 may contribute to aberrant signaling networks sustaining leukemic T cell proliferation, making this knockout tool relevant for oncogenic studies.
Researchers can employ this polyclonal knockout population in diverse functional assays. Western blotting assesses NFAT dephosphorylation, while Fluo-4 AM calcium flux assays quantitate TCR-induced calcium mobilization. NFAT luciferase reporter assays and IL-2 ELISA measure transcriptional and cytokine outputs. Co-immunoprecipitation confirms HOMER2-calcineurin-PLC??1 interactions, and confocal microscopy reveals immune synapse defects. Flow cytometry for CD69 provides a rapid activation readout. These applications position the HOMER2 Knockout Jurkat Polyclonal Cells as a versatile reagent for immunology, calcium signaling, and leukemia research. For further technical details, contact Ascent Research.
