Meeting Abstract

76.6  Monday, Jan. 6 09:15  Gene expression differences in the sexually dimorphic eyes of Euphilomedes carcharodonta (Ostracoda, Crustacea) SAJUTHI, A.; CARRILLO-ZAZUETA, B.; BRONDANSKY, L.; WANG, A.; DUKE, E.; RIVERA, A.S.*; University of the Pacific; University of the Pacific; University of the Pacific; University of the Pacific; University of the Pacific; University of the Pacific arivera@pacific.edu

The difference between a simple light-sensing organ and a complex image-forming eye is largely one of cellular organization. An image forming eye requires intricate patterning of multiple cell types, directed by the expression of eye-development genes. Here we examine gene expression differences between these two eye types. In Euphilomedes ostracods (Crustacea), males (XO) have large complex eyes with standard ommatidial cellular structure, while females (XX) have simple eyes that do not exhibit these structures. We find that sex-specific gene expression differences are in place midway through juvenile development and that the earliest expression differences involve genes whose homologs are involved in various stages of Drosophila eye development. Namely, we observe that some genes involved in eye field specification, rhabdom organization, and lens development are expressed more highly in mid-juvenile males. We also see that mature male eyes express much higher levels of phototransduction gene homologs than female or developing eyes. Our findings suggest that activation of only a small subset of eye development genes is sufficient to pave the way for the growth and organization of this complex crustacean compound eye.