The APP Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the Homo sapiens APP (amyloid-beta precursor protein) gene within the HAP1 cell background. This product consists of a heterogeneous pool of edited cells, generated without clonal selection, providing a versatile loss-of-function model for studying APP-dependent cellular functions. By eliminating full-length APP expression, the model abolishes both amyloidogenic processing??including amyloid-beta peptide generation??and intracellular domain (AICD)-mediated nuclear signaling, enabling researchers to dissect APP??s multifaceted roles in a genetically uniform but non-monoclonal context.
HAP1 cells are a near-haploid, adherent, fibroblast-like cell line originally derived from the male KBM-7 chronic myeloid leukemia line. Their near-haploid karyotype renders them exceptionally amenable to CRISPR/Cas9-mediated gene disruption, as only one allele typically requires targeting, facilitating the generation of complete knockout populations. These cells are widely employed in haploid genetic screening, functional genomics, and drug target validation, offering a simplified genetic background that reduces redundancy and permits high-throughput analyses. Their adherent morphology and compatibility with standard culture conditions further enhance their utility across diverse experimental platforms.
APP is a type I transmembrane protein critical for neuronal development, synapse formation, cell adhesion, and axon guidance. Its proteolytic processing by BACE1 and the ??-secretase complex (PSEN1, PSEN2, nicastrin) generates amyloid-beta peptides and releases the APP intracellular domain (AICD), which translocates to the nucleus and regulates transcription of targets such as GSK3B and p53. Non-amyloidogenic cleavage by ADAM10 precludes amyloid-beta production. APP engages in signaling networks through interactions with adaptor proteins APBB1 (Fe65) and APBA1, as well as receptors LRP1 and SORL1, connecting to Notch, Wnt, PI3K/AKT, and MAPK/ERK pathways. Upstream regulators include neurotrophins NGF and BDNF, retinoic acid, and transcription factors SP1 and REST.
In the HAP1 context, APP knockout provides a unique platform to interrogate APP biology in a non-neuronal yet neurologically relevant environment. The loss of endogenous APP enables structure-function studies, complementation analyses, and investigation of cell adhesion and motility independent of neuronal paradigms. HAP1 cells can be differentiated into neuron-like cells for neurite outgrowth assays recapitulating APP-dependent morphogenesis. The haploid background permits combinatorial CRISPR screens to identify synthetic lethal interactions or modifiers, accelerating Alzheimer??s drug target discovery.
This polyclonal knockout cell population is suited for quantitative analysis of amyloid-beta production (ELISA), APP and fragment detection (western blot), mRNA quantification (RT-qPCR), and subcellular localization (immunofluorescence). Functional studies include AICD reporter assays, co-immunoprecipitation of APP interactors, cell adhesion assays, and neurite outgrowth measurements. Additionally, these cells enable RNA-seq, secretome proteomics, gamma-secretase inhibitor testing, and drug target validation. For further details or sample data, please contact Ascent Research.
