GTSF1 Knockout HAP1 Polyclonal Cells are a targeted loss-of-function model generated through CRISPR/Cas9-mediated disruption of the GTSF1 gene in the HAP1 near-haploid cell line. This polyclonal knockout population consists of a heterogeneous pool of edited cells, providing a robust system for functional studies without the clonal biases associated with single-cell isolation. The product is designed to eliminate GTSF1 expression, enabling precise investigation of its role in piRNA biogenesis and transposon silencing.
HAP1 cells are derived from the KBM-7 chronic myeloid leukemia line, which harbors the BCR-ABL fusion oncogene and exhibits a near-haploid karyotype. The haploid genetic architecture permits efficient single-copy gene targeting and simplifies downstream genetic analyses, as only one allele requires disruption. This feature, combined with the cell line’s stable growth properties and well-characterized signaling pathways, makes HAP1 a versatile host for CRISPR-based functional genomics, particularly for studying evolutionarily conserved cellular mechanisms.
GTSF1 is a critical component of the piRNA biogenesis pathway, functioning through direct interactions with PIWI family proteins, including MIWI and MILI, as well as with TDRD1, TDRKH, MOV10L1, and PLD6. Within this network, GTSF1 facilitates the processing of piRNA precursors and the silencing of transposable elements, processes essential for germline genome integrity. Upstream, GTSF1 expression is regulated by testis-enriched transcription factors such as CREM and STRA8, which respond to retinoic acid signaling. Downstream, GTSF1 activity promotes piRNA-mediated transposon repression and supports spermatid maturation, with its loss leading to spermatogenic failure and male infertility.
Although HAP1 cells originate from a leukemic background, the core piRNA machinery is broadly conserved, and the haploid state offers a simplified platform to dissect GTSF1-dependent molecular interactions in a non-germline context. Disruption of GTSF1 in this model reveals the necessity of piRNA factors for transposon silencing even outside of the germline, providing insights into fundamental genome defense mechanisms. The polyclonal format ensures that observed phenotypes reflect consistent genetic perturbation effects rather than clonal peculiarities.
Researchers can apply this knockout model to a wide array of experimental approaches, including small RNA sequencing and RT-qPCR to profile piRNA intermediates, immunoprecipitation and Western blotting to study protein complexes, and reporter assays to quantify transposon activity. Additionally, the model serves as a valuable tool for investigating the molecular basis of male infertility and for conducting functional screens of piRNA pathway components. For further details or technical support, please contact Ascent Research.
