The HERPUD2 Knockout HAP1 Polyclonal Cells product provides a CRISPR/Cas9-edited polyclonal knockout cell population targeting HERPUD2, an ER membrane protein essential for ER-associated degradation (ERAD) and the unfolded protein response (UPR). The polyclonal format encompasses a mixture of gene-disrupted alleles, suitable for pooled genetic studies without requiring clonal isolation.
HAP1 is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia line, displaying adherent fibroblastoid morphology. Its haploid karyotype simplifies gene editing and enables clear genotype-phenotype correlations in functional genomics studies. HAP1 cells are widely used for CRISPR-based genetic screening and targeted knockout generation due to their genetic stability and well-characterized proteome.
HERPUD2 functions as an ER membrane adaptor in ERAD, activated by ER stress stimuli such as tunicamycin and thapsigargin. Transcription factors XBP1 and ATF6 upregulate HERPUD2 expression under UPR conditions, promoting its interaction with the HRD1?CSEL1L ubiquitin ligase complex, Derlin-1, and the AAA-ATPase VCP/p97. This complex drives retrotranslocation of misfolded proteins from the ER lumen to the cytosol, leading to ubiquitination and proteasomal degradation. The chaperone BiP acts as an upstream sensor, linking HERPUD2 to the UPR machinery.
Disruption of HERPUD2 in HAP1 cells creates a robust loss-of-function system for dissecting ERAD pathway dynamics. The polyclonal knockout population avoids clone-specific artifacts and better represents heterogeneous editing outcomes seen in functional screens. This model enables detailed analysis of ER stress sensitivity, proteasomal degradation efficiency, and the interplay between ER homeostasis and cell survival pathways.
Key research applications include western blotting for ER stress markers (e.g., CHOP, BiP), RT-qPCR quantification of UPR target genes, flow cytometry-based viability profiling under ER stress inducer or proteasome inhibitor treatment, and proteasomal inhibition assays with MG132 or bortezomib. The model is also suited for drug screening to identify ERAD modulators and functional genomics studies of protein quality control. For additional technical details, contact Ascent Research.
