The HDAC4 Knockout HAP1 Polyclonal Cells consist of a CRISPR/Cas9-edited polyclonal population of HAP1 cells harboring targeted disruption of the HDAC4 gene. This knockout model provides a powerful tool for examining the biological functions of HDAC4, a class IIa histone deacetylase implicated in transcriptional repression and chromatin remodeling. The polyclonal nature of the product ensures representation of diverse editing events, offering a robust loss-of-function system for downstream applications without clonal selection biases.
HAP1 is a near-haploid human cell line originally derived from the KBM-7 chronic myeloid leukemia cell line. Its haploid karyotype simplifies genetic analyses, reduces functional redundancy, and facilitates genome-wide knockout and screening approaches. The HAP1 line retains key signaling pathways relevant to hematopoietic malignancies while being amenable to high-throughput functional genomics, making it an ideal host for targeted gene disruption studies.
HDAC4 functions as a transcriptional repressor by deacetylating histone tails, particularly histones H3 and H4, and by forming complexes with transcription factors such as the MEF2 family. HDAC4 activity is tightly regulated by upstream kinases: Ca2+/calmodulin-dependent protein kinase II (CaMKII) and protein kinase A (PKA) phosphorylate HDAC4, promoting 14-3-3 protein binding and subsequent nuclear export. This shuttling relieves repression of MEF2-dependent genes involved in myogenesis and neuronal differentiation. Additionally, HDAC4 interacts with NCoR/SMRT corepressor complexes and modulates other targets including Runx2, p53, and HIF-1??, linking it to diverse pathways such as MAPK signaling, TGF-?? signaling, and calcium-dependent gene regulation.
Disruption of HDAC4 in the HAP1 background is expected to derepress its target genes, providing a cellular model to dissect HDAC4’s role in cancer cell biology, particularly in leukemia where HDAC4 is implicated in proliferation and survival. This knockout system also enables investigation of HDAC4-related pathologies such as brachydactyly mental retardation syndrome, neurodegenerative disorders, and cardiovascular diseases. The near-haploid genome of HAP1 coupled with HDAC4 loss-of-function allows unambiguous linking of phenotypic changes to gene disruption, facilitating drug target validation and mechanistic studies.
Researchers can employ this polyclonal knockout population in a broad range of assays, including western blotting and RT-qPCR to confirm target deregulation, ChIP-seq and RNA-seq for epigenomic and transcriptomic profiling, reporter assays to measure transcriptional activity, immunofluorescence to assess protein localization, and proliferation or drug sensitivity assays to evaluate therapeutic responses. The model is well-suited for functional genomic screens, epigenetic regulation studies, and muscle differentiation research. For additional information, please contact Ascent Research.
