Event Abstract Back to Event Patterning the visual system: Stochastic vs. deterministic choices Michael Perry1, Robert J. Johnston1, Keith Short1 and Claude Desplan1* 1 NYU, Biology, United States Development requires specific gene regulatory programs to generate reproducible body plans that have been selected throughout evolution. To this end, genes are typically expressed in uniform or regionalized patterns in cells of specific tissues. However, stochastic patterning is sometimes utilized to diversify cell fates, particularly in sensory systems. Similar to the human color vision system, the fly eye expresses several light-detecting Rhodopsin proteins that are stochastically distributed. The fly eye is well known for its characteristic lattice of ommatidia (i.e. unit eyes). Underlying this uniformity, expression of light-detecting Rhodopsin proteins defines two main types of ommatidia that are stochastically distributed throughout the retina. The transcription factor Spineless is stochastically expressed in R7 photoreceptors and acts to control this random mosaic pattern. We will explain how a gene can intrinsically choose to be expressed in a stochastic manner and how the cis-regulatory logic embedded in the DNA controls stochastic spineless gene expression. In contrast to other examples of stochastic processes in bacteria or other sensory systems, which rely on stochastic gene activation, the control of spineless relies on broad activation whereas repressive elements act at long range to prevent spineless expression in a random subset of R7 photoreceptors. We will also describe how this stochastic system has evolved convergently in various visual systems and how it has appeared in insects. Other species that develop highly related types of eyes instead chose to have a deterministic and highly regular patterning of the same type of genes. We will explain our advances in our understanding of stochastic gene expression, complex regulation of large genes via long-range interactions, and the logic of organization of regulatory networks that determine cell-type-specific gene expression. Keywords: Color Vision, development, Drosophila, polarized light vision, Retina, photoreceptors Conference: International Conference on Invertebrate Vision, Fjälkinge, Sweden, 1 Aug - 8 Aug, 2013. Presentation Type: Oral presentation preferred Topic: Development and evolution Citation: Perry M, Johnston RJ, Short K and Desplan C (2019). Patterning the visual system: Stochastic vs. deterministic choices . Front. Physiol. Conference Abstract: International Conference on Invertebrate Vision. doi: 10.3389/conf.fphys.2013.25.00015 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Feb 2013; Published Online: 09 Dec 2019. * Correspondence: Dr. Claude Desplan, NYU, Biology, New York, NY, 10003, United States, cd38@nyu.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Michael Perry Robert J Johnston Keith Short Claude Desplan Google Michael Perry Robert J Johnston Keith Short Claude Desplan Google Scholar Michael Perry Robert J Johnston Keith Short Claude Desplan PubMed Michael Perry Robert J Johnston Keith Short Claude Desplan Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.