For instance, in our PPI network we found that Smad ubiquitination regulatory factor-2 (SMURF2), an ubiquitin E3 ligase responsible for proteasome-mediated degradation of enhancer of zeste homolog 2 EZH2 which is a process required for neuron differentiation [73] is present in periodontitis. Here, EZH2 is linked to periodontitis.