Figure 8From: Evolution of clitellate phaosomes from rhabdomeric photoreceptor cells of polychaetes – a study in the leech Helobdella robusta (Annelida, Sedentaria, Clitellata)H. robusta TX. Expression of pigment genes. Whole mount in situ hybridizations stained with NBT/BCIP, stage 10. A. Expression of tryptophan-2,3-dioxygenase. B. Expression of sepiapterin reductase A. For both genes a staining in the eye region is virtually absent.Back to article page