PITPNM1 and retinal degeneration: rdgB mutant flies undergo light-dependent retinal degeneration, a reduced electroretinogram (ERG) response, and a reduced rate of PI(4,5)P2 resynthesis at the PM after PLC activation (Hotta & Benzer, 1970; Harris & Stark, 1977; Yadav et al, 2015).