The L3MBTL3 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited human cell pool with targeted disruption of the L3MBTL3 gene. This polyclonal knockout population provides a loss-of-function model for investigating the biological roles of L3MBTL3, a histone methylation reader and transcriptional repressor, in a near-haploid background suitable for high-throughput functional genomics and leukemia research.
The HAP1 host cell line is a near-haploid derivative of the KBM-7 chronic myeloid leukemia (CML) cell line, characterized by a predominantly haploid male karyotype. Its single allele copy per gene simplifies CRISPR/Cas9-driven knockout generation and enables unambiguous phenotypic analysis, making it a standard model for genetic screens. The leukemic origin of HAP1 cells provides a relevant context for studying chromatin regulator dysfunction in hematological malignancies.
L3MBTL3 encodes a methyl-lysine binding protein that recognizes histone H4K20me1/2 and H3K9me1/2 marks via three MBT repeats, mediating chromatin compaction and gene silencing. It cooperates with the retinoblastoma protein RB1 to repress E2F transcription factor targets, thereby controlling cell cycle entry and differentiation. Upstream regulation involves phosphorylation by CDK1/cyclin B1 and histone methylation by SETD8 and SUV420H1/2 methyltransferases. L3MBTL3 interacts with condensin complexes and histone variant H2A.Z, and its repressive function governs expression of key hematopoietic regulators, including the HOXA cluster, MEIS1, PBX3, and MYC.
In hematopoietic cells, L3MBTL3 functions as a tumor suppressor, and its loss de-represses self-renewal programs that drive leukemogenesis. This knockout model recapitulates genetic lesions observed in acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), and clonal hematopoiesis, allowing mechanistic dissection of epigenetic dysregulation. The haploid HAP1 background enhances the utility for drug sensitivity profiling and synthetic lethality screens aimed at identifying new therapeutic vulnerabilities in L3MBTL3-deficient leukemias.
Applications include functional genomics of chromatin regulators, validation of epigenetic drug targets, and hematopoiesis research. Researchers can measure target gene derepression via RT-qPCR (e.g., HOXA9, MYC), assess histone modification changes by ChIP-qPCR, and monitor cell cycle alterations with flow cytometry. Colony formation assays and drug sensitivity screening with inhibitors targeting SETD8 or SUV420H1/2 enable preclinical evaluation of epigenetic therapies. For further inquiries, please contact Ascent Research.
