Abstract
Replication Protein A (RPA) is a single-strand DNA-binding protein that is found in all eukaryotes. RPA is subjected to multiple posttranslational modifications including serine- and threonine-phosphorylation, poly-ADP ribosylation, and SUMOylation. These modifications are believed to regulate RPA activity through modulating interactions with DNA and partner proteins. This article describes two methods used to detect posttranslational modified RPA: immunofluorescence and immmuoblotting.