Kawamura Lab

I am interested in evolution of color vision and visual systems of vertebrates. Visual pigments (or opsins) are key to understand animal vision and I have studied the genomic organization and spectral properties of opsins of diverse vertebrate species including lizards (American chameleon), birds (pigeon), primates (New World monkeys and prosimians), and fish (zebrafish). Fish and primates are particularly interesting because of their characteristic opsin repertoire possibly related to various visual behaviors.

Zebrafish is quite useful as a model to study regulatory mechanism of opsin expression. Zebrafish retina contains five distinct classes of photoreceptor cells, each expressing a distinct type of opsin gene. Such cell-type-specific opsin expression is a prerequisite of color vision. We isolated all of the visual opsin genes from the zebrafish genome and described their genomic organizations and spectral characteristics (Chinen et al. 2003 Genetics 163:663-675). This has enabled us to carry out systematic GFP-reporter assays using the genomic DNA fragments surrounding the opsin genes. We would like to explore the cis elements and transcription factors regulating the opsin expression by using the transgenic zebrafish whose specific photoreceptor cells are visualized with GFP.