Meeting Abstract

P3.91  Thursday, Jan. 6  Dermal expression of three phototransduction cascade genes in the cephalopod, Octopus bimaculoides RAMIREZ, Desmond*; OAKLEY, Todd; University of California, Santa Barbara; University of California, Santa Barbara ramirez@lifesci.ucsb.edu

Many animals, including mollusks, can detect light using non-eye photoreceptors found in their skin. However, although dermal photo-behaviors are well documented, we know much less about the underlying mechanisms of dermal photoreception, particularly the phototransduction cascades involved. A recent study of skin from the cuttlefish Sepia officinalis, found mRNA expression of r-opsin (Mathger et al. 2010). We have found mRNA expression of three phototransduction pathway genes, r-opsin, G protein α-q and phospholipase C, in the skin of another cephalopod, Octopus bimaculoides. The sequences of the phototransduction cascade genes found in O. bimaculoides skin are almost identical to those found in the eyes of these animals. These results suggest that, as found in other mollusk groups like bivalves and gastropods, cephalopods possess a dermal photoreception system. Unlike the gastropod Lymnaea, however, cephalopods appear to use only the r-opsin phototransduction cascade for both visual and dermal photoreception. Although it is not clear how this dermal photoreception system is used, it may contribute to the body patterning behaviors cephalopods are well known for.