The JAG1 Knockout MCF-7 Polyclonal Cells product comprises a polyclonal population of MCF-7 breast adenocarcinoma cells bearing CRISPR/Cas9-mediated disruption of the JAG1 gene, which encodes the Jagged1 Notch ligand. This knockout model is provided as a heterogeneous pool of edited cells, enabling functional studies of JAG1-dependent Notch signaling in a luminal A breast cancer background. The CRISPR/Cas9 gene-editing strategy introduces targeted loss-of-function mutations within the JAG1 locus, abolishing Jagged1 protein expression and ligand activity. The polyclonal format preserves the genetic diversity of the edited population, mimicking physiological heterogeneity and avoiding clonal artifacts. This product serves as a versatile tool for investigating the role of Jagged1-mediated Notch activation in cancer cell biology.
The parental MCF-7 cell line is a widely used human mammary epithelial adenocarcinoma model, derived from a pleural effusion of a patient with metastatic breast cancer. MCF-7 cells are characterized by estrogen receptor (ER) and progesterone receptor (PR) positivity, classifying them as luminal A subtype, and they retain epithelial morphology with functional hormone signaling. This background makes the knockout model particularly suitable for dissecting Jagged1 contributions to hormone-responsive breast cancer phenotypes, including proliferation, survival, and epithelial-mesenchymal transition (EMT).
JAG1 encodes Jagged1, a transmembrane ligand that initiates canonical Notch signaling through interactions with NOTCH1-4 receptors upon cell-cell contact. Receptor engagement triggers sequential proteolytic cleavages by ADAM10/17 and the gamma-secretase complex, releasing the Notch intracellular domain (NICD), which translocates to the nucleus and forms a transcriptional activation complex with CSL/RBPJ and MAML coactivators. This complex induces the expression of downstream target genes such as HES1, HEY1, HEY2, MYC, CCND1, BCL2, and Survivin, which collectively promote cell proliferation, survival, and EMT. Jagged1 activity is regulated by upstream signals including TGF-beta/SMAD, Wnt/beta-catenin, HIF-1alpha, IL-6/STAT3, and TNF-alpha/NF-kB pathways, and is modulated by interacting partners like DTX1 and NUMB, which influence receptor trafficking and degradation.
In the MCF-7 luminal A breast cancer context, Jagged1-driven Notch signaling contributes to malignant phenotypes by sustaining proliferative capacity and facilitating EMT, a process linked to metastasis and therapy resistance. Disruption of JAG1 expression in these cells abrogates ligand-dependent Notch activation, leading to attenuated transcription of HES/HEY family repressors and downregulation of oncogenic effectors such as MYC and CCND1. This loss-of-function model allows dissection of Jagged1-specific roles independent of other Notch ligands, providing a clean background for studying Notch paralog specificity and crosstalk with hormonal and growth factor pathways. Because MCF-7 cells retain functional ER signaling, the JAG1 knockout system also enables interrogation of bidirectional interactions between Notch and estrogen receptor pathways.
This polyclonal knockout cell population is suitable for a broad range of experimental approaches, including western blotting and RT-qPCR to confirm loss of JAG1 protein and Notch target gene expression, as well as functional assays such as proliferation, apoptosis, and migration/invasion studies to assess EMT and metastatic potential. The cells can be employed in drug screening campaigns to identify or validate Notch pathway inhibitors, and in co-culture systems to evaluate tumor microenvironment interactions. Additionally, the knockout model is compatible with genome-wide transcriptomic analysis via RNA-seq, chromatin immunoprecipitation (ChIP-qPCR) to examine Notch-responsive promoters, and co-immunoprecipitation experiments to dissect receptor-ligand complex dynamics. For further details and custom requirements, please contact Ascent Research.
