PKM and retinitis pigmentosa 1: In the present study, we investigated how PKM2 appears during retinal degeneration, and compared the PKM2 expression within photoreceptors in the two RP models and also in wild-type (WT) on P9 and P19, which are equivalent to the start and end points, respectively, of our culturing protocol (all data obtained from the explant cultures are presented below).