The ARHGAP21 Knockout HAP1 Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal knockout cell population featuring targeted disruption of the human ARHGAP21 gene. This product provides a heterogeneous pool of HAP1 cells harboring a range of loss-of-function mutations within ARHGAP21, avoiding clonal bias while enabling robust assessment of gene function. The polyclonal format is particularly suited to studies where monoclonal selection might mask subtle phenotypic variations, offering a more representative model of gene disruption at the population level.
The HAP1 host line is a near-haploid human cell line derived from KBM-7 chronic myeloid leukemia cells, displaying an adherent fibroblast-like morphology. Due to its haploid genome, HAP1 is a powerful platform for functional genomics, gene trap mutagenesis, and haploid genetic screens, as a single hit can yield complete gene inactivation. This genetic simplicity facilitates unambiguous genotype?Cphenotype correlations in gene-editing experiments, making it a preferred model for systematic loss-of-function studies.
ARHGAP21 encodes a Rho GTPase-activating protein that functions as a negative regulator of Rho family GTPases, including Cdc42, RhoA, and Rac1. By stimulating GTP hydrolysis, ARHGAP21 promotes the inactive GDP-bound state of these molecular switches, thereby dampening downstream effector pathways. Its activity is modulated by upstream inputs such as integrin signaling and growth factor receptors (e.g., EGFR, PDGFR). ARHGAP21 interacts with the coatomer complex, Golgin-97, and the small GTPases ARF1 and ARF6, linking Rho GTPase regulation to intracellular vesicle trafficking and Golgi ribbon organization. This GAP orchestrates actin cytoskeleton remodeling by controlling stress fiber disassembly, focal adhesion turnover, and cell?Cextracellular matrix interactions.
In the HAP1 context, ARHGAP21 loss removes a critical brake on Cdc42, RhoA, and Rac1 signaling, leading to their hyperactivation and consequent dysregulation of actin dynamics and cell adhesion. This disruption may alter migratory behavior, proliferation, and drug sensitivity, phenotypes that are readily quantified in the haploid background. Given the origin from chronic myeloid leukemia, the model holds particular relevance for leukemia research and for dissecting how aberrant Rho GTPase activity contributes to oncogenic transformation and metastasis.
This polyclonal knockout cell population is intended for a broad range of research applications, including functional genomics, Rho GTPase signaling studies, and investigation of actin cytoskeleton regulation. Users can evaluate ARHGAP21 protein levels via Western blot, measure Rho GTPase activity using G-LISA or pull-down assays, and visualize focal adhesion and actin structures by immunofluorescence. Migration and invasion potential can be assessed through scratch wound or Transwell assays, while drug sensitivity profiles may be explored in high-throughput screening formats. The model also supports haploid genetic screens to identify synthetic lethal interactions or resistance mechanisms involving Rho pathway components. For further information, please contact Ascent Research.
