The ATF3 Knockout HEK293T Polyclonal Cells product is a CRISPR/Cas9-edited polyclonal knockout cell population derived from HEK293T cells, in which the ATF3 gene has been disrupted by CRISPR/Cas9-mediated genome editing. This heterogeneous loss-of-function pool provides a powerful tool for studying ATF3-dependent cellular processes without the need for single-cell cloning. The polyclonal format captures a broad range of editing outcomes, enabling robust assessment of ATF3??s function across a diverse genetic background and ensuring experimental reproducibility in population-based assays.
The parental HEK293T cell line is a widely used human embryonic kidney epithelial model that stably expresses the SV40 large T antigen, which facilitates high-level episomal replication of transfected plasmids and robust protein expression. These features make HEK293T cells an optimal host for CRISPR/Cas9 editing and subsequent functional analyses, including transient transfection, reporter gene assays, and protein interaction studies. Their well-characterized signaling networks and rapid growth kinetics further support high-throughput screening and mechanistic dissection of stress-responsive pathways.
ATF3 functions as a stress-inducible transcription factor that integrates diverse cellular stress signals. It is rapidly activated by JNK and p38 MAPK kinases, as well as by endoplasmic reticulum stress sensors IRE1 and PERK, which converge on upstream regulators such as ATF4, c-Jun, and p53. Activated ATF3 forms heterodimers with other bZIP proteins, including c-Jun, JunB, JunD, ATF2, and DDIT3 (CHOP), to transcriptionally modulate target genes. Downstream, ATF3 directly regulates expression of DDIT3, GADD45A, CCND1 (cyclin D1), and BCL2 family members, thereby controlling cell cycle and apoptosis. Additionally, it promotes transcription of pro-inflammatory cytokines IL-6 and TNF-??, linking cellular stress to immune responses. Its activity is further refined by interactions with cofactors such as HDAC1 and Smad3, enabling integration of epigenetic and TGF-?? signals.
In the HEK293T background, ATF3 knockout provides a clean model to dissect these stress-responsive networks without compensation from endogenous ATF3. The ease of transfection and high expression capacity of HEK293T cells accelerate complementation experiments with ATF3 variants, reporter-based monitoring of pathway activity, and biochemical analyses of protein-protein interactions. Since ATF3 is not required for viability under standard culture conditions, this polyclonal knockout pool can be stably maintained, making it highly suitable for stress-challenge experiments, such as treatment with tunicamycin or hydrogen peroxide, and for high-throughput chemical screening to identify modulators of the ER stress or JNK signaling axes.
Typical research applications include investigating cellular stress responses via RNA-seq or phospho-signaling analysis; elucidating transcriptional regulatory networks through ChIP-seq; studying apoptosis and survival mechanisms with Annexin V staining and cell viability assays; analyzing inflammatory signaling by measuring IL-6 and TNF-?? secretion; and performing co-immunoprecipitation to map ATF3 interactions with partners like c-Jun or p53. The knockout cells are well-suited for reporter gene assays monitoring ATF3-responsive promoters and for comparative studies of MAPK pathway activation. For further information or to explore custom applications, please contact Ascent Research.
