Meeting Abstract

P2.71  Saturday, Jan. 5  Do opsins regulate cnidocyte firing in Nematostella vectensis? FALTINE-GONZALEZ, D.Z.*; BABONIS, L.S.; MARTINDALE, M.Q.; Kewalo Marine Lab, Univ of Hawaii; Kewalo Marine Lab, Univ of Hawaii; Kewalo Marine Lab, Univ of Hawaii dylanfg@hawaii.edu

Opsins are light-sensitive proteins used by organisms to perceive changes in light intensity. These proteins have been identified in the eyes of both vertebrates and invertebrates, and even in the photoreceptive tissues of some eyeless organisms. Recently, opsins have even been identified in eyeless cnidarians such as the hydrozoan Hydra magnipapillata, where they are thought to regulate the firing of cnidocytes. Cnidocytes, the stinging cells found only in cnidarians (jellyfish, sea anemones, etc), function in prey capture, movement, and defense of the organism. If opsins are regulating firing in Hydra then it is possible that they also regulate firing in other cnidarians such as Nematostella vectensis, the starlet sea anemone. N. vectensis is a model organism with 19 known opsin-like proteins, none of which has a currently known function. To test whether any of these opsin proteins regulate cnidocyte firing we isolated and cloned all the opsin sequences from the N. vectensis genome and performed in situ hybridizations to examine their expression patterns. Our preliminary results show that opsins are expressed in the ectoderm of various areas of N. vectensis with unique subsets of opsins being expressed specifically in the tentacle tips, mesenteries, and pharynx, in cells adjacent to cnidocytes. To determine if these opsins found adjacent to cnidocytes are regulating cnidocyte firing, we will continue these studies by performing double in situ hybridization to test if other elements of bilaterian phototrandsuction pathways (specifically CNG and arrestin genes) are coexpressed in opsin-expressing cells. Finally, we will then confirm that opsins are regulating cnidocyte firing by performing behavioral experiments.