The ID3 Knockout 143B Polyclonal Cells represent a CRISPR/Cas9-mediated gene disruption model, generated in the human 143B osteosarcoma cell line. This product is supplied as a polyclonal cell population, reflecting a diverse pool of individual editing events that collectively ablate functional ID3 protein expression. By leveraging CRISPR/Cas9 technology, the targeted disruption of the ID3 gene creates a powerful tool for dissecting its role in cellular processes.
The 143B cell line is a highly aggressive and widely employed model of human osteosarcoma, originally derived from a bone tumor. These cells are characterized by a highly tumorigenic and metastatic phenotype, making them an ideal host for studying mechanisms of bone cancer progression. 143B cells enable investigation of tumor growth, invasion, and the molecular determinants of osteosarcoma malignancy in both in vitro and in vivo settings.
ID3 encodes a helix-loop-helix (HLH) protein that functions as a dominant-negative inhibitor of basic helix-loop-helix (bHLH) transcription factors, including E47, E12, and MyoD. By sequestering these bHLH proteins, ID3 blocks their transcriptional activity, thereby repressing differentiation programs and sustaining a proliferative state. ID3 is a key downstream effector in multiple signaling cascades: it is transcriptionally induced by BMP/SMAD1/5/8 and TGF-??/SMAD pathways, as well as by Notch signaling through RBP-J. Additionally, ID3 expression is regulated by Wnt/??-catenin, PI3K/AKT, and MAPK/ERK pathways. Its downstream targets include the cell cycle regulators p21 and p16, and the oncoprotein c-Myc, placing ID3 at the nexus of growth factor and developmental signaling networks. ID3 physically interacts with E47, E12, Tal1, and Ets factors, and cooperates with the retinoblastoma protein (pRb) to modulate cell cycle progression and apoptosis.
In the 143B osteosarcoma background, ID3 overexpression is known to contribute to the maintenance of a dedifferentiated state, promoting tumorigenesis and enhancing angiogenic and metastatic potential. Disruption of ID3 in this cell line therefore provides a critical model for evaluating its contribution to osteosarcoma pathogenesis. The polyclonal ID3 knockout population allows researchers to study the aggregate effects of ID3 loss on tumor cell behavior, including alterations in differentiation, proliferation, and invasive capacity, without the confounding effects of clonal variation.
Typical research applications for these polyclonal ID3 knockout 143B cells include mechanistic studies of osteosarcoma tumor biology, investigation of cell differentiation and proliferation control, cancer stem cell research, and angiogenesis assays. Researchers can employ a range of molecular and cellular assays, such as Western blotting for ID3 and downstream proteins (E47, p21), RT-qPCR for target gene expression, flow cytometry for cell cycle distribution, and transwell migration and invasion assays. Additional functional readouts include colony formation assays, xenograft tumor growth models, immunofluorescence for protein localization, and reporter assays to assess bHLH transcriptional activity. These knockout cells thus serve as a versatile platform for target validation and signaling pathway dissection. For additional information or to discuss custom requirements, please contact Ascent Research.
