Description

The TMEM41B Knockout A549 Cell Line is a CRISPR/Cas9-mediated knockout derivative of the human A549 lung adenocarcinoma cell line, designed to eliminate TMEM41B function. This constitutive loss-of-function model is optimized for investigating TMEM41B roles in autophagy, lipid mobilization, and viral replication. The cell line provides a robust experimental platform for diverse assays without transient transfection artifacts, enabling reproducible genetic perturbation studies.

A549 cells were originally isolated from a 58-year-old male with lung adenocarcinoma and serve as a classical adherent epithelial model for respiratory biology and oncology. They exhibit alveolar type II pneumocyte features and are widely utilized in studies of SARS-CoV-2, flavivirus, and cancer cell signaling. This host background thus ensures the knockout retains physiological relevance for pulmonary disease and infection research.

TMEM41B is an ER transmembrane protein essential for autophagosome biogenesis, acting by recruiting VMP1 and ATG2 to mobilize lipids for phagophore expansion. Upstream regulators include nutrient deprivation, mTOR signaling, ER stress, and type I interferons. Downstream, it controls LC3 lipidation and engages ATG5, SQSTM1/p62, and viral replication complexes. In flavivirus infection, TMEM41B forms ER-derived platforms with NS4A and NS4B, underscoring its dual roles in autophagy and viral replication. Pathway components such as ULK1, BECN1, ATG7, and LC3 further contextualize its function.

In A549 cells, TMEM41B knockout allows dissection of its contribution to autophagy-dependent survival and viral exploitation in a lung epithelial environment. The line is particularly valuable for studying host factors required for SARS-CoV-2 and flavivirus replication, as well as ER stress and lipid metabolism alterations linked to lung adenocarcinoma. This model bridges fundamental cell biology and translational virology.

Applications include western blotting of LC3 conversion, immunofluorescence for autophagy puncta, and co-immunoprecipitation of VMP1 and ATG2. Viral replication assays and RT-qPCR for viral RNA facilitate investigation of host dependency. Additionally, the line supports drug target screening for COVID-19, flavivirus infections, and cancer, plus lipidomic and electron microscopy analyses. For further details, contact Ascent Research.