The AGL Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population of human colorectal adenocarcinoma cells harboring a targeted disruption of the AGL gene. This loss-of-function model eliminates functional glycogen debranching enzyme (GDE) expression, providing a defined system for investigating glycogen metabolism and its dysregulation. The polyclonal format ensures genetic diversity within the edited pool, enabling robust phenotypic screening without clonal selection artifacts.
HT29 cells are a well-characterized human colorectal adenocarcinoma epithelial line, widely used as an intestinal epithelial model. These cells retain key metabolic features of colorectal carcinoma, including reliance on glycolysis and glycogen stores, and exhibit adherent growth suitable for imaging and biochemical assays. Their epithelial origin and capacity for enterocytic differentiation make them relevant for studies at the intersection of cancer biology and metabolic control.
The AGL gene encodes glycogen debranching enzyme, which specifically hydrolyzes ??-1,6-glycosidic branch points in limit dextrin, generating linear chains for further cleavage by glycogen phosphorylase. This reaction releases glucose-1-phosphate and free glucose, both critical outputs of glycogenolysis. AGL is regulated by insulin and glucagon through cAMP-dependent signaling, placing it downstream of nutrient-sensing pathways. It interacts directly with glycogen phosphorylase and functions in concert with glycogen synthase to maintain glycogen structure and glucose homeostasis. Disruption of AGL causes accumulation of phosphorylase-resistant limit dextrin, blocks glycogen degradation, and perturbs glucose mobilization.
In HT29 cells, AGL knockout mirrors the metabolic defect of glycogen storage disease type III, resulting in aberrant glycogen accumulation and altered glucose release. This model is particularly relevant for studying how colorectal cancer cells rewire glycogen metabolism to sustain proliferation under fluctuating nutrient conditions. The polyclonal population captures heterogeneous knockout efficiencies and adaptive responses, reflecting the complexity of tumor microenvironments and enabling investigation of metabolic vulnerabilities that may be exploited therapeutically.
Typical applications include modeling glycogen storage disease type III, interrogating cancer cell glycogen metabolism, and screening compounds that restore or bypass debranching enzyme function. Researchers can validate AGL disruption via western blotting and RT-qPCR, measure glycogen content and debranching enzyme activity, and assess glucose release dynamics. PAS staining visualizes glycogen deposits, while metabolic flux analysis traces carbon through glycogen pathways. These cells provide a versatile platform for dissecting glycogenolytic regulation and evaluating therapeutic strategies. For additional information, please contact Ascent Research.
