The KLHL12 Knockout HAP1 Polyclonal Cells product comprises a CRISPR/Cas9-edited polyclonal population derived from the near-haploid human HAP1 cell line, with disrupted KLHL12 gene function. This heterogeneous pool provides a loss-of-function model for studying KLHL12??s role as a substrate adaptor of the CUL3-RING E3 ubiquitin ligase complex, enabling investigation of Wnt pathway regulation, ubiquitin-mediated proteolysis, ERAD, and COPII vesicle trafficking.
HAP1 is a chronic myeloid leukemia-derived near-haploid cell line with a largely haploid karyotype, simplifying gene disruption. It is widely used for genetic studies in cancer biology and cell signaling due to its hematopoietic origin and robust growth. The line??s genetic stability and ease of manipulation make it an optimal host for constructing knockout polyclonal pools that avoid clonal biases.
KLHL12 encodes a substrate adaptor of the Cullin3-RING E3 ubiquitin ligase (CRL3) complex, which consists of CUL3, RBX1, and a dedicated adaptor. Through its BTB and BACK domains, KLHL12 scaffolds CUL3-RBX1, while its Kelch repeats bind substrates such as the Dishevelled paralogs DVL1/2/3 and the dopamine receptor DRD4. Ubiquitination of DVL promotes proteasomal degradation, inhibiting Wnt/??-catenin signal transduction downstream of WNT ligands and Frizzled receptors, thereby reducing ??-catenin nuclear accumulation and TCF/LEF-mediated target gene expression. Similarly, KLHL12-mediated degradation of DRD4 modulates dopamine receptor surface density. Beyond ubiquitination, KLHL12 interacts with the COPII coat component SEC31A to facilitate formation of enlarged COPII vesicles necessary for collagen and large cargo secretion. KLHL12 activity is influenced by ER stress and neddylation of CUL3, and its function intersects with endoplasmic reticulum-associated degradation (ERAD) pathways.
In HAP1 cells, KLHL12 knockout eliminates CRL3-dependent turnover of key substrates, leading to altered Wnt pathway activity and potential ERAD defects. The near-haploid background ensures uniform gene disruption, facilitating clear phenotype interpretation. This model is particularly pertinent for studying ubiquitin-related mechanisms in a hematopoietic cancer setting and for assessing responses to proteasome inhibitors, given the CML origin of the host line.
These KLHL12 knockout polyclonal cells empower a range of experimental assays: western blotting for KLHL12 and substrate levels (DVL, DRD4), RT-qPCR to quantify Wnt target genes (AXIN2, MYC), co-immunoprecipitation to assess CUL3 complex integrity, proteasome inhibitor (e.g., MG132) treatments to block substrate degradation, immunofluorescence microscopy for SEC31A-labeled COPII vesicles, TOPFlash dual-luciferase reporter assays for Wnt activity, flow cytometry to monitor DRD4 surface expression, and RNA-seq transcriptome profiling. Drug sensitivity studies using proteasome inhibitors like bortezomib can probe cancer-relevant vulnerabilities. The polyclonal format ensures diverse allelic mutations across the population, enhancing robustness in pooled screening formats. For detailed protocols or to explore custom application inquiries, please contact Ascent Research.
