The 3-core representation of the G2* second neighborhood network restricted to DNA damage repair response. Shown is the result of clustering the components of the G2* second neighborhood network arising from the original four Tax binding proteins known to be involved in the cellular DNA damage response. There are five clusters with three bridge proteins; DNA-PK is one of the bridge proteins. For clarity in drawing the network, we do not show edges from these three proteins to the individual proteins in the clusters. The numbers on the edges from these proteins to the clusters count the number of edges from each protein to proteins in each cluster.