Modeling the competition between the RAD 51 and the RPA in binding to the single-stranded DNA using a one-dimensional lattice model.

A crucial step of homologous recombination in the DNA repair mechanism is the search for homology between DNA molecules closely followed by strand exchange. This step is governed by the nucleoprotein RAD51, which competes with Replication Protein A (RPA) to saturate single-stranded DNA (ssDNA) overhangs. Such interactions are stochastic in nature. Therefore, we have developed a dynamic lattice model to model the competition between RAD51 and RPA molecules binding to the single-stranded DNA. This will assist us in better understanding the real-time dynamics observed by single-molecule microscopy. With this model, we will study various binding parameters' effects on each protein’s saturation level.