T4 gene 32 protein (gp 32), encoded by gene 32 of bacteriophage T4, is a single-stranded DNA (ssDNA)-binding protein essential for T4 phage DNA replication and repair. It coordinately binds to and stabilizes transiently formed ssDNA regions, playing an important structural role during T4 phage DNA replication. This protein is also widely used to stabilize and label ssDNA regions for observing intracellular DNA structures by electron microscopy.
This protein can be used in Recombinase Polymerase Amplification (RPA) to bind displaced strands during the reaction and prevent further strand displacement.