AKT1 and retinal degeneration: PTEN, an inhibitor of the AKT/mTOR signaling pathway, enables RPE cells to function normally, but the activation of the AKT/mTOR pathway triggers RPE dedifferentiation and retinal degeneration (Kim et al., 2008; Lee et al., 2011; Zhao et al., 2011; Jiang et al., 2016).