Anti-eIF2a (phospho S51) Antibody - Identical to Abcam (ab131505) and Novus (NB100-81896)

Phosphorylation of eukaryotic translation initiation factor 2 alpha at serine 51 is a central event in the integrated stress response, executed by kinases such as PERK, GCN2, PKR, and HRI to repress global translation under conditions of ER stress, amino acid deprivation, viral infection, or heme deficiency. The Antibodies.com polyclonal reagent is raised against this specific phospho-S51 epitope, allowing selective detection of the activated form of eIF2a without cross-reactivity to the unphosphorylated protein.

Validated for western blot, immunohistochemistry, and immunofluorescence on Human, Mouse, and Rat samples, the antibody recognizes the expected band in immunoblotting and provides cytoplasmic and perinuclear signal in imaging of stressed cells. Pairing with thapsigargin-, tunicamycin-, or arsenite-treated controls is recommended to confirm phospho-specificity in experimental workflows.

Supplied as 200 µl of unconjugated rabbit IgG in a liquid vial. For storage, aliquot and freeze at -20 °C, avoiding repeated freeze-thaw cycles to preserve phospho-epitope binding. Working dilutions typically fall between 1:500 and 1:2000 for western blot and between 1:50 and 1:500 for IHC, depending on sample preparation and detection chemistry. For research use only.