The <it>Pax </it>gene <it>eyegone </it>facilitates repression of eye development in <it>Tribolium</it>

• Main Authors: ZarinKamar Nazanin, Yang Xiaoyun, Bao Riyue, Friedrich Frank, Beutel Rolf, Friedrich Markus
• Format: Article
• Language: English
• Published: BMC 2011-04-01
• Series: EvoDevo
• Online Access: http://www.evodevojournal.com/content/2/1/8

<p>Abstract</p> <p>Background</p> <p>The <it>Pax </it>transcription factor gene <it>eyegone </it>(<it>eyg</it>) participates in many developmental processes in <it>Drosophila</it>, including the Notch signaling activated postembryonic growth of the eye primordium, global development of the adult head and the development of the antenna. In contrast to other <it>Pax </it>genes, the functional conservation of <it>eyg </it>in species other than <it>Drosophila </it>has not yet been explored.</p> <p>Results</p> <p>We investigated the role of <it>eyg </it>during the postembryonic development of the red flour beetle <it>Tribolium castaneum</it>. Our results indicate conserved roles in antennal but not in eye development. Besides segmentation defects in the antenna, <it>Tribolium eyg </it>knockdown animals were characterized by eye enlargement due to the formation of surplus ommatidia at the central anterior edge of the compound eye. This effect resulted from the failure of the developing gena to locally repress retinal differentiation, which underlies the formation of the characteristic anterior notch in the <it>Tribolium </it>eye. Neither varying the induction time point of <it>eyg </it>knockdown nor knocking down components of the <it>Janus kinase</it>/<it>Signal Transducer and Activators of Transcription </it>signaling pathway in combination with <it>eyg </it>reduced eye size like in <it>Drosophila</it>.</p> <p>Conclusions</p> <p>Taken together, expression and knockdown data suggest that <it>Tribolium eyg </it>serves as a competence factor that facilitates the repression of retinal differentiation in response to an unknown signal produced in the developing gena. At the comparative level, our findings reveal diverged roles of <it>eyg </it>associated with the evolution of different modes of postembryonic head development in endopterygote insects as well as diversified head morphologies in darkling beetles.</p>