EIF2A Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 human cell line, designed to disrupt the EIF2A gene. This heterogeneous loss-of-function model provides a representative pool of edited alleles for functional studies of the alternative translation initiation factor EIF2A. The polyclonal format is particularly suitable for genomic and proteomic analyses where population-level effects are critical. This product serves as a robust tool for dissecting EIF2A-dependent pathways in a near-haploid genetic background.
The HAP1 cell line is a near-haploid human fibroblast-like line originally established from a patient with chronic myeloid leukemia. Its haploid karyotype, with only a small duplication on chromosome 15, greatly simplifies genetic manipulation and phenotypic interpretation. HAP1 cells are widely used in haploid genetic screens and CRISPR-based functional genomics because the single allele copy eliminates confounding effects from genetic redundancy. The adherent, fibroblastoid morphology supports a broad range of cell-based assays, making it an ideal host for knockout models.
EIF2A encodes an alternative translation initiation factor that mediates cap-dependent or IRES-driven translation independently of the eIF2 ternary complex. During cellular stress, such as ER stress or amino acid deprivation, eIF2?? kinases (PERK, GCN2, HRI, PKR) phosphorylate eIF2??, inhibiting global protein synthesis. EIF2A bypasses this block by delivering methionyl initiator tRNA (Met-tRNAi) to the 40S ribosomal subunit in cooperation with eIF5B and GTP. This enables selective translation of stress-responsive mRNAs encoding transcription factors ATF4 and CHOP, key effectors of the integrated stress response.
In the haploid HAP1 context, EIF2A knockout eliminates a major alternative translation pathway, unmasking cellular dependency on non-canonical initiation during proteotoxic challenges. This model allows unambiguous dissection of EIF2A-mediated translational reprogramming under stress conditions that induce eIF2?? phosphorylation, such as hypoxia or chemotherapeutic exposure. It is especially valuable for studying how cancer cells exploit EIF2A to sustain protein synthesis and survive therapy-induced stress, revealing potential vulnerabilities.
Research applications include haploid genetic screens to identify synthetic lethal partners, mechanistic investigation of the integrated stress response, and elucidation of resistance mechanisms in cancer. Experimentally, users can perform Western blotting for EIF2A and phospho-eIF2??, RT-qPCR for ATF4 and CHOP, ribosome profiling, dual-luciferase reporter assays for cap-independent translation, flow cytometry for stress markers, and cell viability assays under tunicamycin or amino acid starvation. For further details, please contact Ascent Research.
