Prolonged depolarising afterpotentials in red-eyed Drosophila

Abstract

After prolonged exposure to blue light, retinula cells R1 to R6 of white-eyed Drosophila remain depolarised in darkness. Long wavelength light (e.g. orange) reverts this dark depolarization. We have reproduced these results in red-eyed Drosophila (wild-type and cinnabar) by using whole field illumination. Even under these conditions, red-eyed flies require an order of magnitude more light than white-eyed flies. This is attributed to the presence of the screening pigment.