The Phospho-STAT3 (Ser727) antibody is a critical tool for studying the activation and functional regulation of Signal Transducer and Activator of Transcription 3 (STAT3), a transcription factor involved in numerous cellular processes, including proliferation, differentiation, apoptosis, and immune responses. STAT3 is activated via phosphorylation at two key residues: tyrosine 705 (Tyr705) and serine 727 (Ser727). While Tyr705 phosphorylation facilitates STAT3 dimerization, nuclear translocation, and DNA binding, Ser727 phosphorylation modulates its transcriptional activity and mitochondrial functions.
The phosphorylation of Ser727 is mediated by various kinases, such as mTOR, ERK, and CDK5. in response to cytokines, growth factors, or stress signals. This post-translational modification fine-tunes STAT3’s transcriptional output by influencing cofactor recruitment, chromatin remodeling, and interactions with mitochondrial proteins. Dysregulated Ser727 phosphorylation has been implicated in cancer progression, inflammation, and autoimmune diseases, making it a biomarker of interest in pathological research.
Phospho-STAT3 (Ser727)-specific antibodies enable the detection of this modification in techniques like Western blotting, immunofluorescence, and immunohistochemistry. Researchers use these antibodies to investigate STAT3 signaling dynamics, therapeutic target validation (e.g., kinase inhibitors), and disease mechanisms. Validation of antibody specificity is essential, as cross-reactivity with other phosphorylated STAT family members or unrelated proteins can lead to misinterpretation. Overall, this antibody is indispensable for unraveling STAT3’s dual roles in homeostasis and disease.