The AP3S2 Knockout HT29 Polyclonal Cells are a polyclonal population of HT29 human colorectal adenocarcinoma cells with CRISPR/Cas9-mediated disruption of the AP3S2 gene. This knockout model enables investigation of the sigma2 subunit of adaptor protein complex 3 (AP-3) in lysosomal trafficking and cellular homeostasis. The polyclonal pool reflects heterogeneous editing events, providing a robust loss-of-function model for population-based phenotypic studies.
The HT29 cell line is a well-characterized human colorectal adenocarcinoma line with epithelial morphology, originally isolated from a primary tumor. These adherent cells express intestinal markers and serve as a standard model for investigations of intestinal epithelial biology, colon cancer progression, and drug responses. Their genetic background and robust growth characteristics make them compatible with a wide range of functional assays including high-content imaging and transcriptomic profiling.
AP3S2 encodes the sigma2 subunit of the heterotetrameric AP-3 complex, which is critical for cargo selection and vesicle formation at the trans-Golgi network and endosomes. The AP-3 complex, comprising AP3S2 together with AP3B1, AP3D1, and AP3M1, recognizes tyrosine-based sorting motifs on transmembrane cargo proteins such as LAMP1, LAMP2, and CD63, directing them to lysosomes and lysosome-related organelles. AP3S2 function is transcriptionally regulated by TFEB and MITF, master regulators of lysosomal biogenesis, and its activity is coordinated with the Arf1 GTPase cycle and clathrin coat assembly. Disruption of AP3S2 impairs AP-3 complex integrity, leading to missorting of lysosomal hydrolases and membrane proteins, ultimately compromising lysosomal function and cellular homeostasis.
In HT29 colorectal adenocarcinoma cells, AP3S2 knockout provides a physiologically relevant platform to dissect lysosomal trafficking defects in the context of epithelial tumor biology. This model allows researchers to explore how impaired AP-3 function affects processes such as autophagy, exosome secretion, and cell migration, which are implicated in cancer progression and metastasis. Additionally, it offers insights into Hermansky-Pudlak syndrome, a genetic disorder linked to AP-3 deficiencies, and may reveal vulnerabilities in colorectal cancer cells that rely on lysosomal pathways for growth and survival.
This polyclonal knockout cell population is suitable for a broad array of experimental applications, including Western blotting and immunofluorescence localization studies of LAMP1/LAMP2, lysosomal enzyme activity assays, LysoTracker staining for lysosomal pH monitoring, and cell viability (MTT) or migration/invasion (Transwell) assays. It can be employed in drug sensitivity screens targeting lysosomal pathways, flow cytometric analysis of surface receptor trafficking, and transcriptomic studies (RNA-seq) to identify AP3S2-dependent gene networks. For additional information or custom cell engineering solutions, please contact Ascent Research.
