EIF4EBP3 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population derived from the HAP1 cell line. The EIF4EBP3 gene has been disrupted via CRISPR/Cas9-mediated gene targeting, producing a heterogeneous pool of cells with loss-of-function of the target gene. This polyclonal format maintains population diversity while eliminating clonal selection bias, making it suitable for studying translational control and mTORC1 signaling in a near-haploid background.
HAP1 is a near-haploid derivative of the KBM-7 chronic myeloid leukemia (CML) cell line, isolated from a patient in blast crisis. Its haploid karyotype simplifies gene editing and functional genomics due to single alleles for most genes. The leukemic origin provides a relevant model for hematopoietic malignancies, and HAP1 cells retain key CML features, including BCR-ABL fusion-independent proliferation, aiding dissection of oncogenic signaling pathways.
EIF4EBP3 encodes a translational repressor that binds eIF4E, preventing recruitment of eIF4G and blocking cap-dependent translation initiation. This repression is relieved by mTORC1-mediated phosphorylation, which occurs downstream of growth factor receptors, insulin, and PI3K/AKT signaling. Phosphorylated EIF4EBP3 releases eIF4E, allowing assembly of the eIF4F complex and stimulation of protein synthesis. Thus, EIF4EBP3 acts as a critical integrator of nutrient and mitogenic signals with translational output. Core interacting partners include eIF4E, eIF4G, and mTORC1 components like raptor and mTOR. It functions alongside other 4E-BP family members, notably 4E-BP1, but its distinct regulatory patterns remain under investigation.
The polyclonal knockout of EIF4EBP3 in HAP1 cells enables dissection of translational control in leukemic cells. Cancer cells often rely on dysregulated cap-dependent translation for proliferation; loss of EIF4EBP3 relieves eIF4E repression, potentially enhancing translation of specific mRNAs linked to cell cycle, survival, and metabolism. The haploid background eliminates gene redundancy, making functional consequences more penetrant. This model facilitates study of mTORC1-dependent and independent roles of EIF4EBP3, with relevance to drug resistance and adaptive mechanisms in CML.
The cells are suited for polysome profiling, reporter gene assays, and western blotting to assess translation, mTOR activity, and phosphorylation of downstream targets like eIF4E and S6K. Proliferation and drug sensitivity assays with mTOR inhibitors or chemotherapeutics help evaluate the role of translational control in therapy response. They also support metabolic disorder studies and validation of EIF4EBP3 as a drug target in cancer. For further information, please contact Ascent Research.
