title: First identification and localization of a visual pigment in Hydra (Cnidaria, Hydrozoa).
abstract: The cnidarian Hydra does not possess identified photoreceptive structures or specialized cells for light detection; nevertheless, it shows a marked photosensitivity. So far no evidence has been previously reported about the localization of the proteins involved in the photoresponse. We used polyclonal antibodies and immunofluorescence microscopy on whole-mount Hydra to identify a putative rhodopsin-like protein. Our results show an immunoreactivity in the ectodermal layer of Hydra, which corresponds in position to the nervous epidermal sensory cells. These data provide the first identification of a rhodopsin-like protein in a phylogenetically old invertebrate and give a new insight into the Hydra photoreceptive response.
authors.affiliation: Istituto di Cibernetica del CNR, Napoli, Italy. carlom@biocib.cib.na.cnr.it
authors.forename: C
authors.initials: C
authors.lastname: Musio
authors.forename: S
authors.initials: S
authors.lastname: Santillo
authors.forename: C
authors.initials: C
authors.lastname: Taddei-Ferretti
authors.forename: L J
authors.initials: LJ
authors.lastname: Robles
authors.forename: R
authors.initials: R
authors.lastname: Vismara
authors.forename: L
authors.initials: L
authors.lastname: Barsanti
authors.forename: P
authors.initials: P
authors.lastname: Gualtieri
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D005455:Fluorescent Antibody Technique; D006829:Hydra / Q000737:chemistry*; D007150:Immunohistochemistry; D017956:Photoreceptor Cells, Invertebrate / Q000502:physiology*; D012168:Retinal Pigments / Q000032:analysis*; D012243:Rhodopsin / Q000737:chemistry; D017299:Rod Opsins / Q000276:immunology
chemical_list: D012168:Retinal Pigments; D017299:Rod Opsins; D012243:Rhodopsin