Meeting Abstract

P1.148  Saturday, Jan. 4 15:30  Eye development during regeneration and asexual reproduction in the basal bilaterian Convolutriloba longifissura HARMON, C. L. *; SIKES, J. M.; University of San Francisco; University of San Francisco clharmon@usfca.edu

While morphological comparisons of photoreceptor anatomy suggest that animal eyes evolved multiple times independently, the molecular conservation of Pax6’s role in eye development suggests common ancestry. Studies in acoels have revealed that Pax6 is not expressed in the cells of the eye during embryonic development, suggesting that other transcription factors were co-opted to initially pattern eyes in early bilaterians. Given their unique phylogenetic position as basal bilaterians, acoels provide a promising system to search for genes that may have patterned eye development before the split with the 3 major superclades. We have utilized next generation sequencing to develop an eye-enriched transcriptome from the acoel Convolutriloba longifissura and have characterized the spatiotemporal expression of candidate genes with promising roles in the specification of photoreceptors during postembryonic development. Functional characterization of these candidates along with other conserved eye development genes is currently underway. These findings suggest that the initial evolution of photoreceptors likely occurred without specification by Pax6 but via alternative developmental patterning and provide support to the independent evolution of eyes within the Metazoa.