The DNAJC15 Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population with targeted disruption of the DNAJC15 gene. Derived from the NCI-H1975 human lung adenocarcinoma cell line, this heterogeneous pool provides a robust loss-of-function model for studying the mitochondrial co-chaperone MCJ. The knockout was generated by CRISPR/Cas9-mediated gene editing, which introduces permanent disruption without defined clonal selection, thereby maintaining population-level genetic diversity. This model is suited for functional investigation of DNAJC15 in mitochondrial biology, apoptosis, and chemoresistance.
NCI-H1975 is a female non-smoker-derived lung adenocarcinoma cell line from pleural effusion metastasis, harboring the EGFR L858R/T790M double mutation. This genotype confers resistance to first- and second-generation EGFR tyrosine kinase inhibitors and drives constitutive pro-survival signaling. As a widely used model of acquired TKI resistance, the line enables examination of metabolic adaptation and apoptotic evasion in a clinically relevant context. The combination of oncogenic EGFR signaling and DNAJC15 knockout allows dissection of mitochondrial regulation in drug-resistant NSCLC.
DNAJC15 encodes MCJ, a mitochondrial inner membrane co-chaperone that interacts with HSPA9 and GRPEL1. MCJ negatively regulates respiratory complex I activity, controlling oxidative phosphorylation and ATP synthesis. Epigenetic silencing via promoter CpG island methylation by DNMT1/DNMT3B removes this inhibition, leading to increased respiration, reduced ROS, and impaired cytochrome c release. Downstream, BAX/BAK activation and caspase-9/-3 processing are suppressed, conferring apoptosis resistance. The MCJ-HSPA9-complex I axis integrates mitochondrial metabolic sensing with cell death programs.
DNAJC15 knockout in NCI-H1975 recapitulates the epigenetic silencing frequently observed in EGFR-mutant lung adenocarcinomas, where MCJ loss contributes to chemoresistance. The model highlights how disruption of mitochondrial complex I regulation drives metabolic reprogramming and apoptosis evasion under oncogenic stress. It also offers a relevant system to study hypoxia response and to evaluate epigenetic therapies aimed at restoring MCJ expression.
Applications include Seahorse metabolic flux analysis, ATP luminescence assays, and mitochondrial complex I activity measurement to assess bioenergetics. ROS detection and caspase-3/7 activation assays quantify redox and apoptotic responses. Drug sensitivity profiling and flow cytometry for Annexin V/PI enable chemoresistance studies. The polyclonal format supports assessment of population-level heterogeneity. For further information, please contact Ascent Research.
