The KLHL22 Knockout HAP1 Polyclonal Cells product provides a CRISPR/Cas9-edited polyclonal knockout cell population targeting the KLHL22 gene in the HAP1 host cell background. This loss-of-function model enables investigation of KLHL22-dependent processes without altering other genomic loci, yielding a broadly representative population of gene-disrupted cells. The polyclonal format supports diverse experimental designs, including pooled functional screens and biochemical studies, while avoiding clonal selection artifacts. Researchers can utilize these cells to dissect the role of KLHL22 in signaling networks where complete gene disruption is required, leveraging the robust editing efficiency of the CRISPR/Cas9 system to generate a mixed population with targeted loss of the adaptor protein.
The HAP1 cell line is a near-haploid chronic myeloid leukemia-derived model originally isolated from the KBM-7 patient line, harboring a BCR-ABL fusion oncogene characteristic of CML. Its karyotype consists of a single set of chromosomes with a disomic fragment of chromosome 8, creating a genetically stable haploid background that simplifies knockout studies by eliminating recessive masking. HAP1 cells are widely adopted for functional genomics and CRISPR-based genetic screens due to their ability to expose loss-of-function phenotypes directly. The endothelial-like adherent growth properties and rapid proliferation make HAP1 suitable for high-throughput assays and reproducible biochemical experiments, while the oncogenic BCR-ABL signaling provides a disease-relevant context for studying cancer cell biology.
KLHL22 functions as a substrate adaptor for the CUL3-RING E3 ubiquitin ligase, mediating the ubiquitination and proteasomal degradation of DEPDC5, a core component of the GATOR1 complex that inhibits mTORC1. This process is activated by amino acids through a mechanism involving recruitment of KLHL22 to the lysosomal surface by the Ragulator complex (LAMTOR1-5) and active Rag GTPases (RagA/B, RagC/D). Degradation of DEPDC5 relieves GATOR1-mediated repression, enabling mTORC1 translocation and activation. Consequently, KLHL22 connects upstream nutrient signals to downstream mTORC1 effectors such as S6K1 and 4E-BP1, controlling protein synthesis, and also regulates autophagy factors like ULK1 and TFEB. The KLHL22-CUL3-DEPDC5 axis thus sits at a hub integrating ubiquitin-mediated proteolysis, amino acid sensing, and mTORC1 signaling.
In the HAP1 near-haploid system, KLHL22 knockout creates a clean genetic model for dissecting mTORC1 regulation without confounding alleles. The disruption of DEPDC5 degradation allows examination of constitutive GATOR1 activity and its impact on nutrient signaling, autophagy, and cell growth. This model is particularly valuable for studying aberrant mTORC1 activity in cancers, including the CML-like background of HAP1 cells where BCR-ABL signaling may intersect with nutrient-sensing pathways. The polyclonal population preserves heterogeneous knockout outcomes, mimicking therapeutic scenarios where partial pathway inhibition occurs, and enables screening for genetic modifiers or chemical compounds that restore or bypass KLHL22 loss.
Typical research applications include amino acid stimulation or starvation assays with phosphorylation readouts of S6K1 and 4E-BP1 by western blotting, cycloheximide-chase experiments to monitor DEPDC5 degradation kinetics, and co-immunoprecipitation studies probing interactions with CUL3 or Ragulator components. The cells are also suitable for autophagy flux measurements using LC3-I/II markers, flow cytometry for mTORC1-dependent cell size changes, and cell proliferation assays under metabolic stress. These polyclonal knockout cells support drug screening for mTORC1 modulators and large-scale functional genomics screens, making them a versatile resource for investigating metabolic disorders, cancer metabolism, and neurodegeneration. For further product information and technical support, please contact Ascent Research.
