The Expression and Role of Melanopsin in Paralichthys dentatus

• Published in: The FASEB journal 2015-04, Vol.29 (S1)
• Main Authors: Akinnola, Ifeolu, Kingston, Alexandra, Robinson, Phyllis, Cronin, Thomas
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.29.1_supplement.lb103

Abstract only Less than two decades ago a research on the light sensitive skin cells of Xenopus laevis led to the discovery of the visual pigment known as melanopsin. Now, it's known that melanopsin is expressed in the vertebrate retina, as well as in the brain and skin of certain species. The presence of melanopsin has been studied in several fish species. In fact, zebrafish have five melanopsin genes. Paralichthys dentatus (Summer flounder) is commonly found in the ocean water off the east coast of North America. A flat fish where the adult form is bilaterally asymmetrical, this flounder uses dynamic patterning for camouflage and signaling. It has been shown that there are visual opsin genes present within the dermal tissue of the flounder, suggesting the tissue is also light sensitive. Previous work has shown that there is an expression of rhodopsin and cone opsin in the dermal tissue of the flounder. The activation of visual opsins within retinal cells causes hyperpolarization. In contrast, the activation melanopsin is known to cause cells to depolarize. We hypothesize that melanopsin is used in a “push‐pull” system, in addition to visual opsins, to regulate the flounder's dynamic patterning. In addition melanopsin also activates at a slower rate than visual opsins, making it a good candidate for our hypothesized “push‐pull” system. Our aim is to identify the melanopsin gene using a flounder transcriptome and confirm the expression of melanopsin within dermal and retinal tissue. We also hope to confirm the presence of the components needed for proper phototransduction within the cells melanopsin is expressed in. Funding Source: NIH grant number 5T34GM008663‐18 to the UMBC MARC‐U STAR Program; The Office of Naval Research Basic Research Challenge grant number N00014‐10‐0989 to T.W.C.