The ADRM1 Knockout HeLa Polyclonal Cells constitute a CRISPR/Cas9-mediated loss-of-function model for investigating the ubiquitin-proteasome system (UPS). This polyclonal population carries heterogeneous ADRM1 gene disruptions, abolishing expression of the Rpn13 ubiquitin receptor without the need for single-cell isolation. ADRM1 normally resides in the 19S regulatory particle of the 26S proteasome, where it recognizes polyubiquitinated substrates and facilitates their deubiquitination and translocation into the 20S core. Disruption of ADRM1 therefore impairs substrate turnover and provides a versatile platform for UPS research.
HeLa cells are a human cervical adenocarcinoma line immortalized by HPV18. Their epithelial origin, robust growth kinetics, and comprehensive molecular characterization make them a widely used model for cancer biology. Expression of viral E6 and E7 oncoproteins inactivates p53 and Rb, creating a sensitized background in which to interrogate ADRM1-dependent regulation of stress responses, cell cycle control, and apoptosis.
At the molecular level, ADRM1 acts as a key ubiquitin receptor, binding polyubiquitin chains and recruiting the deubiquitinase UCHL5. It is transcriptionally regulated by NRF2 and is induced by ER and oxidative stress. ADRM1 interacts with proteasome subunits Rpn2 (PSMD1) and PSMD4, and its activity controls the stability of downstream targets such as p53, p21, p27, and Bax. Consequently, ADRM1 ablation disrupts the degradation of these factors, leading to dysregulated cell cycle progression, impaired DNA damage checkpoints, and altered apoptosis sensitivity. The ADRM1 interactome thus integrates cellular stress signals with proteasomal degradation.
In the HeLa milieu, where p53 and Rb are already suppressed, ADRM1 knockout reveals p53-independent proteasomal functions and exposes vulnerabilities linked to HPV-driven oncogenesis. These cells are particularly useful for investigating resistance mechanisms to proteasome inhibitors like bortezomib, as ADRM1 loss can sensitize or alter drug response. Additionally, the model enables dissection of how viral transformation rewires the UPS, shedding light on tumor-specific dependencies.
Researchers can employ these cells for Western blotting of ADRM1 and ubiquitin-conjugated proteins, proteasome activity assays, ubiquitin affinity purification, cell cycle analysis by flow cytometry, and apoptosis assays. Applications span functional UPS studies, cancer cell biology, drug target validation, and proteasome inhibitor resistance research. For further information and custom projects, please contact Ascent Research.
