The AGAP3 Knockout HT29 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout population derived from the human colorectal adenocarcinoma HT29 cell line, in which expression of the Arf GTPase-activating protein AGAP3 has been permanently disrupted to create a loss-of-function model for studying endosomal trafficking and actin dynamics.
The HT29 cell line is a well-characterized model of human colorectal adenocarcinoma, harboring key oncogenic mutations in the APC, TP53, and BRAF genes while maintaining microsatellite stability. These genetic alterations lead to dysregulated Wnt signaling, defective apoptosis, and constitutive MAPK pathway activation, recapitulating aspects of colorectal tumorigenesis. HT29 cells grow as adherent epithelial cultures and are extensively employed to investigate tumor cell biology, drug sensitivity, and tumor microenvironment interactions.
AGAP3 functions as an Arf GTPase-activating protein that is recruited to intracellular membranes by the phosphoinositide PIP3. Upon binding PIP3, AGAP3 accelerates GTP hydrolysis on Arf GTPases, notably ARF1, ARF5, and ARF6, thereby switching them to an inactive GDP-bound state. This activity lies downstream of phosphoinositide 3-kinase (PI3K) and activated receptor tyrosine kinases such as EGFR, linking extracellular signals to endosomal sorting and actin filament dynamics. AGAP3 also associates with clathrin adaptor complexes, further implicating it in vesicle formation and cargo selection. By controlling Arf GTPase activity, AGAP3 serves as a critical node coordinating membrane trafficking with cytoskeletal rearrangements.
In the context of HT29 cells, which already harbor hyperactivated oncogenic pathways, disruption of AGAP3 provides a tool to dissect how endosomal trafficking and actin remodeling contribute to colorectal cancer phenotypes. Because AGAP3 operates downstream of PI3K and EGFR, its loss may alter the subcellular localization or activity of ARF-dependent processes, potentially impacting cell migration, matrix invasion, and proliferative signaling. The microsatellite stable, genetically defined background of HT29 cells ensures reproducible studies of how AGAP3-dependent membrane dynamics intersect with the known tumor suppressor and oncogenic mutations present in this line.
This polyclonal AGAP3 knockout model is suited for a variety of functional studies, including western blotting to confirm loss of AGAP3 protein, RT-qPCR to monitor expression of Arf targets, and immunofluorescence to visualize actin cytoskeleton organization and endosomal marker distribution. Cell migration and invasion assays can assess the impact of AGAP3 disruption on metastatic potential, while proliferation and drug sensitivity profiling enable investigation of therapeutic vulnerabilities. Co-immunoprecipitation experiments using ARF-GTP-specific probes can directly measure altered Arf activation states. For further details or technical support, please contact Ascent Research.
