The HERC1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the HERC1 gene in the near-haploid human HAP1 cell line. This polyclonal format provides a heterogeneous pool of cells carrying diverse HERC1 gene disruptions, enabling robust loss-of-function studies without clonal selection biases. The gene-edited population serves as a versatile model to investigate HERC1-dependent cellular processes in a genetically simplified background.
The HAP1 cell line is derived from the male KBM-7 chronic myeloid leukemia line and is characterized by a near-haploid karyotype, with a single copy of most chromosomes except for a heterozygous ~30 Mb fragment from chromosome 15. This simplified genetic landscape facilitates genetic screens, eliminates confounding effects of allelic variation, and enhances the penetrance of knockout phenotypes. HAP1 cells have been broadly adopted for functional genomics, drug discovery, and signal transduction studies due to their stable haploid state and ease of genome editing.
HERC1 encodes a large HECT domain-containing E3 ubiquitin ligase that catalyzes the covalent attachment of ubiquitin to substrate proteins, targeting them for proteasomal degradation or altering their localization and activity. Through its ubiquitination activity, HERC1 regulates key nodes in the mTOR signaling axis, membrane trafficking, and cell cycle progression. It directly interacts with and ubiquitinates the tumor suppressor TSC2, a negative regulator of mTORC1, thereby modulating mTOR pathway activity in response to growth factors and cellular stress signals. HERC1 also interacts with clathrin heavy chain, ARF proteins, and ubiquitin-conjugating enzyme E2, positioning it at the interface between endomembrane dynamics and nutrient sensing. Consequently, HERC1 influences downstream effectors such as RHEB, mTORC1 substrates, and cell cycle regulators.
In the HAP1 near-haploid background, disruption of HERC1 unmasks its roles in pathways that are frequently dysregulated in disease. HERC1 mutations are linked to neurodevelopmental disorders, macrocephaly, intellectual disability, and cancer, making this knockout model a valuable tool for dissecting genotype-phenotype relationships. The polyclonal population allows assessment of HERC1-dependent phenotypes at the population level, such as alterations in proliferative capacity, mTORC1 signaling activity, or membrane receptor trafficking, without the confounding influence of clonal adaptation.
This polyclonal HERC1 knockout cell pool is suitable for functional genomics screens, mTOR pathway interrogation, ubiquitination profiling, and drug target validation. Researchers can employ western blotting to monitor HERC1 and downstream phospho-proteins, perform co-immunoprecipitation to map interactomes, or use flow cytometry for cell cycle and receptor expression analysis. Proliferation and phospho-signaling assays further support mechanistic studies. For additional information, contact Ascent Research.
