LRRK2 and Parkinson disease: The main cell components (protein degradation, cell cycle, mitochondria, PI3K–AKT–mTOR pathway and inflammation) and the main Parkinson’s-disease-associated proteins (parkin, PTEN-induced putative kinase 1 (PINK1), DJ-1, leucine-rich repeat kinase 2 (LRRK2), glucocerebrosidase (GBA), and F-box protein 7 (FBXO7)) are depicted with the multiple interactions that exist between them.