title: Eye development and photoreceptor differentiation in the cephalopod Doryteuthis pealeii.
abstract: Photoreception is a ubiquitous sensory ability found across the Metazoa, and photoreceptive organs are intricate and diverse in their structure. Although the morphology of the compound eye in Drosophila and the single-chambered eye in vertebrates have elaborated independently, the amount of conservation within the 'eye' gene regulatory network remains controversial, with few taxa studied. To better understand the evolution of photoreceptive organs, we established the cephalopod Doryteuthis pealeii as a lophotrochozoan model for eye development. Utilizing histological, transcriptomic and molecular assays, we characterize eye formation in Doryteuthis pealeii Through lineage tracing and gene expression analyses, we demonstrate that cells expressing Pax and Six genes incorporate into the lens, cornea and iris, and the eye placode is the sole source of retinal tissue. Functional assays demonstrate that Notch signaling is required for photoreceptor cell differentiation and retinal organization. This comparative approach places the canon of eye research in traditional models into perspective, highlighting complexity as a result of both conserved and convergent mechanisms.
authors: Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA grossjm@pitt.edu kmkoenig@gmail.com.
authors: Kristen M
authors: KM
authors: Koenig
authors: Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
authors: Peter
authors: P
authors: Sun
authors: Department of Zoology, Oregon State University, Cordley Hall 3029, Corvallis, OR 97331, USA.
authors: Eli
authors: E
authors: Meyer
authors: Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA grossjm@pitt.edu kmkoenig@gmail.com.
authors: Jeffrey M
authors: 0000-0002-9422-6312
authors: JM
authors: Gross
mesh_terms: D000818:Animals; D049830:Cephalopoda / Q000196:embryology* / Q000378:metabolism*; D005123:Eye / Q000196:embryology* / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology; D010786:Photoreceptor Cells / Q000166:cytology* / Q000378:metabolism*
keywords: Cephalopod; Eye evolution; Lophotrochozoa; Squid