Anti-Stat5 (phospho-S726/731) Antibody

Phosphorylation of signal transducer and activator of transcription 5 at the dual serine cluster S726 and S731 represents a regulatory event distinct from the better-characterised tyrosine-694 activation site, and this rabbit polyclonal reagent from Antibodies.com is raised specifically against the doubly phosphorylated form of the protein. The antibody is supplied as 100 µl of purified immunoglobulin at 1 mg/ml in phosphate buffered saline containing 0.05% sodium azide at approximately pH 7.2, unconjugated so it can be paired with the secondary detection system of the user's choice. Validation has been performed for Western blot and immunohistochemistry, and the reagent recognises the phosphorylated target in human, mouse, and rat samples. Because the epitope is restricted to the activated, serine-phosphorylated state, the antibody is used to probe cytokine- and growth-factor-driven signalling cascades where serine-phosphorylated Stat5 has been linked to distinct transcriptional programmes, including studies of mammary epithelial differentiation, hematopoietic lineage decisions, and lymphocyte downstream signalling. Researchers using it for immunoblotting resolve whole-cell lysates on SDS-PAGE, transfer to nitrocellulose or PVDF, and probe with the antibody at working dilutions in blocking buffer; for immunohistochemistry on formalin-fixed paraffin-embedded sections, antigen retrieval is followed by overnight incubation and chromogenic or fluorescent detection. The vial should be kept refrigerated, aliquoted if it will be accessed repeatedly, and freeze-thaw cycles avoided to preserve antibody activity.