JAM3 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 near-haploid human cell line. This product provides a loss-of-function model for JAM3 (junctional adhesion molecule 3), a member of the immunoglobulin superfamily of cell adhesion molecules. By disrupting the JAM3 gene across a heterogeneous cell pool, researchers can study the collective functional consequences of JAM3 deficiency in hematopoietic cell models, without the clonal biases of single-cell-derived lines. The polyclonal format retains genetic diversity, enabling robust phenotypic screening and reducing the confounding effects of clonal variation in CRISPR-based experiments.
The HAP1 parental line is a near-haploid human cell line originally isolated from KBM-7 chronic myelogenous leukemia cells, which harbor the BCR-ABL oncogenic fusion. Its near-haploid karyotype simplifies genetic analyses, making HAP1 a staple in haploid genetic screens and targeted knockout studies. HAP1 cells retain characteristics of the myeloid lineage and are widely used to investigate hematopoietic signaling, oncogenic mechanisms, and drug sensitivity. Combining JAM3 knockout with this well-characterized background creates a versatile platform for studying adhesion-dependent processes in a leukemia-relevant context.
JAM3 encodes a transmembrane tight junction protein that mediates both homophilic and heterophilic interactions with JAM2, ITGAV/ITGB3, and ITGAM/ITGB2 integrins. These interactions maintain epithelial and endothelial barrier integrity and regulate leukocyte adhesion and transendothelial migration. Upstream signals such as TNF-alpha, VEGF, IL-1beta, and FGF2 modulate JAM3 function, which in turn activates PI3K/AKT1 and ERK/MAPK1/3 pathways, and governs RHOA and RAC1 GTPase dynamics. JAM3 associates with tight junction scaffolds ZO-1, cingulin, and the Par3?CPar6?Catypical PKC polarity complex, linking cell?Ccell contacts to cytoskeletal remodeling and transcriptional outcomes, including cyclin D1 expression and MMP-2/MMP-9 upregulation.
In the HAP1 hematopoietic context, JAM3 disruption enables investigation into how adhesion and tight junction proteins influence leukemic cell behavior, including proliferation, migration, and interactions with the endothelial microenvironment. Given HAP1??s BCR-ABL-positive status, the knockout model is particularly suited to dissect the interplay between oncogenic kinase signaling and junctional proteins in leukemogenesis. Moreover, the near-haploid background facilitates synthetic lethality screens and drug?Cgene interaction studies, allowing researchers to identify vulnerabilities created by JAM3 loss in CML-derived cells. This model can also inform on mechanisms driving bone marrow niche retention and egress of hematopoietic cells, processes central to leukemia progression and therapeutic resistance.
JAM3 Knockout HAP1 Polyclonal Cells enable haploid genetic screens, transendothelial migration assays (e.g., ECIS), cell adhesion quantification, and immunofluorescence-based analyses of junctional proteins such as ZO-1 and cingulin. Signaling readouts including phospho-AKT1 and phospho-MAPK1/3 can be assessed by western blot or phospho-kinase arrays, and transcriptomic changes by RNA-seq. These cells are valuable for drug target validation and phenotypic screens in inflammatory disease, cancer metastasis, and spermatogenic failure research. For additional information, please contact Ascent Research.
