The DMXL1 Knockout NCI-H1299 Polyclonal Cells product consists of a genomically diverse population of NCI-H1299 human lung adenocarcinoma epithelial cells that have been subjected to CRISPR/Cas9-mediated disruption of the DMXL1 locus. As a polyclonal knockout pool, this product avoids the clonal selection biases inherent in single-cell?Cderived knockout lines, providing a heterogeneous loss-of-function model that better represents bulk population responses. The cells are supplied as a live, ready-to-culture stock optimized for downstream functional assays, with the knockout status verified at the population level by sequencing and/or immunoblot analysis.
The parental NCI-H1299 cell line was originally established from a lymph node metastasis in a patient with non-small cell lung carcinoma (NSCLC). These cells display an epithelial morphology and are widely employed as a metastatic lung adenocarcinoma model due to their rapid proliferation, tumorigenic potential in xenograft assays, and well-characterized signaling networks. NCI-H1299 cells harbor mutations in TP53, which contribute to their transformed phenotype and make them a valuable system for studying oncogenic signaling pathways, including the mTORC1 axis, in a cancer-relevant background.
DMXL1 (Dmx-like 1) encodes a large scaffolding protein that is an integral component of the Ragulator complex (LAMTOR1?C5) and the biogenesis of lysosome-related organelles complex-1 (BLOC-1). Through these complexes, DMXL1 physically interacts with LAMTOR1, LAMTOR2, LAMTOR3, LAMTOR4, LAMTOR5, BLOC1S1, BLOC1S2, and SNAPIN, coordinating amino acid?Cinduced mTORC1 activation and lysosomal biogenesis. DMXL1 is regulated by inputs such as amino acid availability, synaptic activity, Rab3a, and calcium signaling. Downstream, DMXL1 promotes mTORC1 kinase activity, leading to phosphorylation of ribosomal protein S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1), and facilitates lysosomal acidification and synaptic vesicle exocytosis. Disruption of DMXL1 uncouples the Ragulator from mTORC1, impairing lysosomal recruitment of mTOR and attenuating downstream anabolic signaling.
In the context of NCI-H1299 lung adenocarcinoma cells, DMXL1 knockout provides a unique experimental system to dissect the dependency of mTORC1 signaling on the Ragulator complex in NSCLC. Because mTORC1 is frequently hyperactivated in lung cancer, loss of DMXL1 is expected to inhibit cell proliferation, reduce phospho-S6K and phospho-4E-BP1 levels, and perturb lysosomal homeostasis, as evidenced by altered LysoTracker staining and LAMP1 immunofluorescence patterns. This model thus enables researchers to investigate how scaffold-dependent mTORC1 regulation contributes to the metabolic reprogramming and growth of metastatic lung cancer cells, independent of growth factor receptor inputs.
Typical research applications include western blotting for phosphorylated S6K and 4E-BP1 to assess mTORC1 activity, RT-qPCR profiling of mTORC1 target genes, LysoTracker staining for lysosomal acidification, MTT-based cell proliferation assays, immunofluorescence detection of lysosomal markers, and drug sensitivity screens with rapamycin or other mTOR inhibitors. The polyclonal knockout format also makes these cells amenable to pooled genetic screening and bulk functional genomics experiments. For further technical specifications, protocol recommendations, or to inquire about custom gene-edited cell products, please contact Ascent Research.
