Whole cell patch clamp recordings of P{Rh1+4}; ninaE17 photoreceptors demonstrates light-dependent changes in intracellular calcium result from the influx of external calcium. Application of thapsigargin results in a steady increase of intracellular calcium (demonstrating the existance of IP3-sensitive stores of calcium). Even after complete depletion of calcium the light response is not abolished. Instead the rise in intracellular calcium is associated with a partial desensitisation (adaptation) of the electrical response. There is no functional link between average intracellular calcium and adaptation recovery mechanisms. Localised intracellular calcium drives aspects of photoreceptor cell regulation.
Expression of Rh4ninaE.P rescues the ability of ninaE17 larvae to strongly discriminate between 18[o]C and 24[o]C in a binary choice thermotaxis assay.
A UV sensitive rhodopsin transgene.