Anti-p53 (phospho-S20) Antibody

This rabbit polyclonal antibody from Antibodies.com is a phosphorylation site-specific reagent that recognizes the p53 tumor suppressor only when serine 20 is phosphorylated. Phosphorylation at Ser20 is a hallmark of the cellular DNA damage response: it is carried out primarily by Chk1 and Chk2 kinases and stabilizes p53 by disrupting its interaction with the E3 ligase Mdm2, thereby supporting downstream transcription of cell-cycle arrest and apoptotic targets.

The reagent is supplied at 1 mg/ml in phosphate buffered saline (PBS), pH approximately 7.2, with 0.05% sodium azide as a preservative. Each vial contains 100 µl of antibody for use in Western blot and immunohistochemistry workflows. The host species is rabbit and the antibody is unconjugated, allowing researchers to pair it with secondary reagents of their choice.

Validated reactivity covers human and mouse samples, making the antibody useful for translational cancer research, genotoxicity studies, and investigations of ATM/ATR pathway activation. Because it is site-specific, it complements total-p53 antibodies: comparing the phospho-S20 signal to total p53 reveals the fraction of p53 actively engaged in stress signaling rather than baseline expression.

Short-term storage should be refrigerated in the original vial to preserve antibody activity; for longer-term use, the reagent can be aliquoted and stored frozen, protected from light to minimize degradation through repeated freeze-thaw cycles. The polyclonal format provides recognition of multiple epitopes around the phospho-S20 region, which can be advantageous when sample preparation conditions vary.