The EFR3A Knockout A-549 Polyclonal Cells product comprises a CRISPR/Cas9-edited polyclonal population of A-549 human lung adenocarcinoma cells carrying a targeted disruption of the EFR3A gene. This mixed knockout cell pool enables functional investigation of EFR3A-dependent processes without the limitations of clonal selection, providing a biologically heterogeneous model system that retains the genetic diversity of the edited population. The use of a polyclonal knockout format is particularly suited for pooled screening approaches and for studying cellular phenotypes that may be influenced by clonal variation.
The host A-549 cell line is an adherent epithelial line originally derived from a 58-year-old male with lung adenocarcinoma. These cells serve as a widely used model for alveolar type II epithelium and are extensively employed in lung cancer research, viral infection studies, and drug screening applications. Their robust growth characteristics and well-characterized signaling networks make them an ideal background for examining the consequences of EFR3A loss in a cancer-relevant context.
EFR3A functions as a plasma membrane scaffold protein that directly binds and regulates phosphatidylinositol 4-kinase III?? (PI4KA), thereby controlling local synthesis of phosphatidylinositol 4-phosphate (PI4P). Acting downstream of growth factor receptors and mTORC1, EFR3A forms complexes with TTC7B and FAM126A to recruit PI4KA to the membrane. The resulting PI4P pools coordinate endocytic trafficking through Rab GTPases and endocytic adaptors, and also interface with the autophagy machinery by interacting with ULK1 and ATG13. Consequently, EFR3A is a critical node linking extracellular signals to phosphatidylinositol signaling, endocytosis, and autophagy flux.
In the context of A-549 lung adenocarcinoma cells, knockout of EFR3A is expected to deplete plasma membrane PI4P, thereby compromising receptor-mediated endocytosis and cargo sorting, as well as impairing autophagy initiation and progression. Such disruptions can alter cell proliferation, stress responses, and drug sensitivity, making this model highly relevant for dissecting the contributions of the EFR3A-PI4KA-PI4P axis to tumor cell biology. The model also provides a platform for exploring potential roles of EFR3A in neurodegenerative processes where PI4P-dependent membrane trafficking is implicated.
Researchers can employ this knockout cell pool in a variety of quantitative assays to probe EFR3A function. For example, PI4P quantification by immunofluorescence or lipid extraction can directly measure the impact on phosphoinositide metabolism, while western blotting and RT-qPCR confirm EFR3A disruption and assess downstream effector expression. Autophagy flux assays (LC3-II turnover with bafilomycin A1) and flow cytometry-based proliferation analyses reveal the functional consequences on cellular homeostasis. Additionally, phospho-signaling arrays enable systematic mapping of altered mTOR and growth factor receptor pathways. These applications support target validation studies in lung adenocarcinoma and broader investigations of membrane scaffolding proteins. For further technical details or to discuss custom projects, please contact Ascent Research.
