ATF3 (Activating Transcription Factor 3) is a stress-inducible nuclear protein belonging to the ATF/CREB family of basic leucine zipper (bZIP) transcription factors. It plays a dual regulatory role in cellular responses to stress, inflammation, DNA damage, and metabolic disturbances, acting either as a transcriptional repressor or activator depending on cellular context and binding partners. ATF3 expression is typically low under normal conditions but rapidly upregulated by diverse stimuli, including cytokines, hypoxia, oxidative stress, and endoplasmic reticulum stress, through signaling pathways such as MAPK, NF-κB, and integrated stress response (ISR).
ATF3 antibodies are essential tools for studying its expression patterns, subcellular localization, and molecular interactions. These antibodies are commonly validated for applications like Western blotting, immunohistochemistry (IHC), immunofluorescence (IF), and chromatin immunoprecipitation (ChIP). Most commercial ATF3 antibodies target specific epitopes within its conserved N-terminal transactivation domain or C-terminal bZIP domain. Researchers frequently use them to investigate ATF3's roles in cancer (where it may act as an oncogene or tumor suppressor), neurodegenerative diseases, metabolic disorders, and immune regulation. Proper validation via knockout controls or siRNA-mediated knockdown is critical due to potential cross-reactivity with other ATF/CREB family members. The antibody's performance may vary depending on post-translational modifications or alternative splicing isoforms of ATF3.