Abstract
The p53 tumor suppressor has a central role in many key cellular processes including the DNA damage response, aging, stem cell differentiation, and fertility. p53 undergoes extensive regulatory post-translational modification through events such as phosphorylation, acetylation, methylation, and ubiquitylation. Here, we describe western blotting-based methodology for the detection and relative quantification of individual phosphorylation events in p53. While we focus on well-established N-terminal modifications for the purpose of illustration, this approach can be used to investigate other post-translational modifications of the protein, drawing upon a broad range of commercially available modification-specific antibodies.