Anti-MEF2A (phospho T319) Antibody

This phosphorylation-specific rabbit polyclonal IgG antibody from Antibodies.com selectively recognizes MEF2A only when threonine 319 within the transcription activation domain is phosphorylated, the regulatory site directly modified by p38 MAPK (MAPK14/p38alpha and MAPK11/p38beta). The reagent was raised against a synthetic phosphopeptide matching the human MEF2A sequence surrounding Thr319 (V-T(p)-T-P-S, amino acid range 296–345, UniProt Q02078), then purified by affinity chromatography using the epitope-specific phosphopeptide; non-phospho-specific IgG was removed by passage over the corresponding non-phosphopeptide column, ensuring detection of the phosphorylated isoform alone.

Reactivity has been confirmed in human, mouse, and rat samples, supporting immunofluorescence work in cardiac myocyte, skeletal myoblast, and neuronal systems where p38-driven MEF2A activation is investigated. The unconjugated, liquid format (1.0 mg/mL in PBS containing 50% glycerol, 0.5% BSA, and 0.02% sodium azide) is supplied as a 200 µl vial and is typically used at a working dilution of 1:50–1:200. Pairing the reagent with a compatible fluorescent secondary enables visualization of Thr319 phosphorylation-dependent MEF2A nuclear localization and signal redistribution in response to stimuli such as phenylephrine, serum, EGF, or stress-kinase activation.

Because the target is a transient post-translational modification, preservation of the phospho-epitope during sample handling is critical: rapid fixation, appropriate permeabilization, and refrigeration of the vial at -20 °C with aliquoting to limit freeze-thaw cycles are recommended. Used alongside a total MEF2A antibody as a normalization control, the reagent supports studies of cardiomyocyte hypertrophy, skeletal myogenic differentiation, neuronal survival, and p38 MAPK pathway crosstalk with GSK3β signaling.