The E2F5 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population designed for loss-of-function studies of the E2F5 gene in the HAP1 cell line. This heterogeneous pool preserves population diversity, enabling representative investigation of gene function without single-cell clonal selection bias.
The HAP1 cell line is a near-haploid human fibroblastoid line derived from the KBM-7 chronic myeloid leukemia background. With a male karyotype and adherent morphology, HAP1 cells feature a haploid genome in many chromosomes, simplifying gene disruption and functional analysis. This makes HAP1 a powerful platform for genetic screens, pathway dissection, and functional genomics research.
E2F5 is a transcriptional repressor that partners with TFDP1 and the pocket protein RBL2/p130 to form a DNA-binding complex that targets E2F consensus sites, repressing cell cycle genes such as CCNE1, CCNA2, and CDC2/CDK1. Upstream, TGF-beta receptor signaling via SMAD2/3 induces CDK inhibitors p21 and p27, which inhibit Cyclin D-CDK4/6 and promote p130-mediated repression. Disruption of E2F5 thus relieves this repression, leading to upregulation of these targets and activation of the transcription factor E2F1. Additional interactions include RBL1/p107 and the DREAM complex component LIN9, integrating signals for cell cycle exit and differentiation.
In HAP1 cells, E2F5 knockout provides a clean model to study cell cycle control and TGF-beta signaling. The near-haploid background ensures unambiguous loss-of-function phenotypes, facilitating dissection of E2F5’s role as a tumor suppressor-like repressor in a leukemia-derived context. Researchers can assess how loss of E2F5 alters cell proliferation, cell cycle distribution, and response to TGF-beta or CDK inhibitors, and perform chemical screens to identify vulnerabilities or synthetic lethal interactions.
Applications include western blot and RT-qPCR for validation, flow cytometry for cell cycle analysis, and proliferation assays. The cells are suitable for luciferase reporter assays to monitor E2F-dependent transcription, co-immunoprecipitation to study protein complexes, and RNA-seq for transcriptome-wide impact. They can also be used in drug sensitivity assays against cell cycle-targeted agents. As a versatile polyclonal knockout resource, this model accelerates functional genomics and drug discovery efforts. For additional technical details, contact Ascent Research.
