Anti-STAT3 (phospho S727) Antibody

Raised in rabbit, this unconjugated polyclonal IgG antibody from Antibodies.com selectively detects Signal Transducer and Activator of Transcription 3 (STAT3) only when phosphorylated at serine 727, a regulatory site associated with maximal transcriptional output and mitochondrial recruitment following cytokine stimulation.

Supplied as a 100 µl liquid aliquot in a single vial, the reagent is validated for Western blot detection of phosphorylated STAT3 in human samples. Phospho-Ser727 lies outside the SH2 domain and is phosphorylated independently of the canonical Tyr705 activating site, most often through ERK1/2 or mTOR pathways in response to growth factors, cellular stress, or oncogenic cues. The polyclonal format increases the likelihood of capturing the phosphorylated epitope under denaturing SDS-PAGE conditions, and the unconjugated format allows flexible pairing with HRP-, fluorophore-, or biotin-conjugated secondary reagents of the researcher's choosing.

Typical research contexts include tracking STAT3 serine phosphorylation kinetics after IL-6, EGF, or serum stimulation, profiling pathway activation in cancer cell lines and primary tissue lysates, and complementing antibodies against total STAT3 or phospho-Tyr705 to dissect the dual-phosphorylation code that governs STAT3 dimerization, nuclear accumulation, and mitochondrial function.