DISSERTATION RESEARCH: Opsin Evolution in Mysid Shrimp: A Model for Spectral Tuning

Brigham Young University, Provo UT

Investigators

Abstract

A grant has been awarded to Dr. Keith Crandall and Ms. Megan Porter at Brigham Young University to study the visual pigment gene in mysid shrimp (Mysidacea:Mysidae). Visual pigments consist of an opsin protein and associated receptors responsible for the detection of light, making vision possible. The wavelengths of light that visual pigments can detect differ between species, where differences in wavelength detection are due to changes in the opsin gene. This provides an opportunity for organisms to 'tune' visual pigments to the light present in the environment. Mysid shrimp, where species occur in different aquatic habitats with respect to light, are an appropriate model system to investigate this spectral tuning. The goal of this research is to evaluate the relationship among environment, the sequences of the opsin gene, and the wavelengths of light mysid species from different habitats are capable of detecting. This will be accomplished by constructing the phylogenetic relationships among the mysid species being studied, determining the sequence of the opsin gene found in each species, and measuring the wavelengths of light that each visual pigment absorbs. Visual pigments are proteins that belong to a large family of receptors that have been identified as critical in cellular communication systems, including the detection of hormones, neurotransmitters, odorants, and photons. However, very little is understood about invertebrate opsins. By elucidating the mechanisms controlling the tuning of visual pigments to different wavelengths in mysid shrimp, this study will provide a framework for testing opsin evolution in other organisms. Additionally, the mysid shrimps are an important crustacean group ecologically, providing a large food base for many species in both freshwater and marine ecosystems. Mysid species are also commonly used as aquatic bioindicators. This study will be the first to construct the phylogenetic relationships within a large group of mysid species and will provide the necessary framework for future studies in ecology, toxicology, and evolution.