{"id":405,"date":"2017-09-22T13:19:04","date_gmt":"2017-09-22T17:19:04","guid":{"rendered":"http:\/\/sites.miamioh.edu\/tomoyasulab\/?page_id=405"},"modified":"2017-09-27T21:11:01","modified_gmt":"2017-09-28T01:11:01","slug":"previous-works","status":"publish","type":"page","link":"https:\/\/sites.miamioh.edu\/tomoyasulab\/research\/previous-works\/","title":{"rendered":"Previous works"},"content":{"rendered":"<h1 style=\"text-align: left\"><span style=\"color: #008080\">Diversification\u00a0of insect\u00a0wings<\/span><\/h1>\n<p>The impressive diversity of insect wings makes them an excellent model to study the molecular basis behind morphological evolution. We\u00a0have been investigating the conserved and diverged aspects of genetic mechanisms responsible for wing development in various insects, including the fruit fly (<em>Drosophila<\/em>) and the red flour beetle (<em>Tribolium<\/em>), in order to elucidate the changes in genetic mechanisms that have contributed to the evolution and diversification of insect wings.<\/p>\n<p>The two pairs of wings on extant insects have often undergone evolutionary modification. In <em>Drosophila<\/em>, the forewing is used for flight, whereas the hindwing (haltere) is highly reduced and used only for balance. The Hox gene <em>Ultrabithorax<\/em> (<em>Ubx<\/em>) modifies the hindwing by repressing various wing genes. In contrast, no Hox input is necessary for forewing formation, and therefore, the forewing is considered to be a Hox-free (or default) state. In <em>Tribolium<\/em>, modification of wings is, in a way, reversed. It is the forewing (elytron) that is modified, while the hindwing retains more ancestral wing characteristics. \u00a0Using the larval RNAi technique, we revealed that the elytron is a Hox-free state despite its diverged morphology, and that Ubx cancels the modifications to maintain the rather typical insect wing morphology through activating wing genes in <em>Tribolium<\/em>. This finding suggests the intriguing possibility that the diversity of insect wing morphology might have been facilitated by the divergent use of a Hox transcription factor as an activator or a repressor in different lineages. Currently, we are further analyzing the action of Ubx through identifying Ubx response elements from the <em>Tribolium<\/em> genome by chromatin profiling.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-425 size-large\" src=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/COIS-2017-Figure1-1024x840.jpg\" width=\"525\" height=\"431\" srcset=\"https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/COIS-2017-Figure1-1024x840.jpg 1024w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/COIS-2017-Figure1-300x246.jpg 300w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/COIS-2017-Figure1-768x630.jpg 768w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/COIS-2017-Figure1.jpg 1729w\" sizes=\"auto, (max-width: 525px) 100vw, 525px\" \/><\/p>\n<p><em>References:<\/em><\/p>\n<ul>\n<li>Tomoyasu, Y.\u00a0<em>Ultrabithorax<\/em> and the evolution of insect forewing\/hindwing differentiation. Current Opinion in Insect Science. 19, 8-15 (2017) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2017-COIS-Tomoyasu.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Ravisankar, P., Lai, Y., Sambrani, N., Tomoyasu, Y. * Comparative developmental analysis of <em>Drosophila<\/em> and <em>Tribolium<\/em> reveals conserved and diverged roles of <em>abrupt<\/em> in insect wing evolution. Developmental Biology. 409 (2), 518-529 (2016) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2016-DB-Ravisankar.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Linz, D.M., Tomoyasu, Y. RNAi screening of developmental toolkit genes: A search for novel wing genes in the red flour beetle <em>Tribolium<\/em><em>castaneum<\/em>. Development Genes and Evolution. 225 (1), 11-22 (2015) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2015-DGE-Linz.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Tomoyasu, Y., Arakane, Y., Kramer, K.J., Denell, R.E. Repeated co-options of exoskeleton formation during wing-to-elytron evolution in beetles. Curr Biol. 19(24):2057-65. (2009) <a href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2009-Curr-Biol-Tomoyasu.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/li>\n<li>Tomoyasu Y., Wheeler S.R., Denell R.E. <em>Ultrabithorax<\/em> is required for membranous wing identity in the beetle <em>Tribolium castaneum<\/em>. Nature. 433(7026):643-7.\u00a0(2005) <a href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2005-Nature-Tomoyasu.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/li>\n<\/ul>\n<h1><span style=\"color: #008080\">A dual evolutionary origin of insect wings?<\/span><\/h1>\n<p>RNAi analyses for wing genes in <em>Tribolium<\/em> resulted in several interesting findings (for example, Linz and Tomoyasu 2015 DGE). Among these studies, perhaps the analysis of the <em>vestigial<\/em> (<em>vg<\/em>) gene is the most intriguing one, which provided us with new insights into the origin of insect wings. Despite the fact that insect wings are often used as an example of morphological novelty, the origin of insect wings remains a mystery and is regarded as a major conundrum in biology. Over a century of debates and observations have culminated into two prominent hypotheses on the insect wing origin: the paranotal origin hypothesis and the exite origin hypothesis. The paranotal hypothesis connects the origin to lateral extensions of the tergum (dorsal body wall), while the exite hypothesis essentially proposes that wings formed from an outgrowth and\/or branch of the pleural tissue (the most proximal leg element). Despite accumulating efforts to unveil the origin of insect wings, neither hypothesis has been able to surpass the other.<\/p>\n<p>Through the functional analysis of <em>vg<\/em>, a critical wing gene, we found that there are two <em>vg<\/em>-dependent tissues in the \u201cwingless\u201d first thoracic segment (T1) of the <em>Tribolium<\/em> beetle. Further investigation using other wing genes has revealed that these two tissues are wing serial homologs (i.e. these tissues and wings share common ancestry) in the wingless segment. In addition, homeotic mutant analysis revealed that the merger of the two wing serial homologs is essential to form an ectopic wing on T1. Intriguingly, these two T1 wing serial homologs may actually be homologous to the two proposed wing origins (tergal\/paranotal and pleural\/exite). Therefore, the <em>vg<\/em>-dependent tissues in T1 could be wing serial homologs present in (or reverted to) a more ancestral state, and their merger to form a complete wing provides compelling functional evidence for the dual origin of insect wings, which may allow us to unify two prominent wing origin hypotheses. This finding provided a new and exciting direction for our research.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-509\" src=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/wing-origin-hypotheses-1024x483.jpg\" alt=\"\" width=\"525\" height=\"248\" srcset=\"https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/wing-origin-hypotheses-1024x483.jpg 1024w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/wing-origin-hypotheses-300x141.jpg 300w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/wing-origin-hypotheses-768x362.jpg 768w\" sizes=\"auto, (max-width: 525px) 100vw, 525px\" \/><\/p>\n<p><em>References:<\/em><\/p>\n<ul>\n<li>Tomoyasu, Y., Ohde, T., Clark-Hachtel C.M. What serial homologs can tell us about the origin of insect wings. F1000Research. 6: 268 (2017) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2017_F1000.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Clark-Hachtel C.M., Tomoyasu Y. \u00a0Exploring the origin of insect wings from an evo-devo perspective. Current Opinion in Insect Science. 13, 77-85 (2016) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2016-COIS-Clark-Hachtel.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Clark-Hachtel C.M., Linz D.M., Tomoyasu Y. Insights into Insect Wing Origin Provided by Functional Analysis of <em>vestigial<\/em> in the Beetle<em>, Tribolium castaneum<\/em>. Proc Natl Acad Sci U S A. 110(42):16951-6. (2013) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2013-PNAS-Clark-Hachtel.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<\/ul>\n<h1><span style=\"color: #008080\">Functional significance of beetle elytra<\/span><\/h1>\n<div class=\"page\" title=\"Page 1\">\n<div class=\"section\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-426\" src=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/SR-Fig2-ver2-1024x615.jpg\" alt=\"\" width=\"525\" height=\"315\" srcset=\"https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/SR-Fig2-ver2-1024x615.jpg 1024w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/SR-Fig2-ver2-300x180.jpg 300w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/SR-Fig2-ver2-768x461.jpg 768w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2016\/01\/SR-Fig2-ver2-2000x1200.jpg 2000w\" sizes=\"auto, (max-width: 525px) 100vw, 525px\" \/><\/p>\n<p>Coleoptera (beetles) is a massively successful order of insects, distinguished by their evolutionarily modi ed forewings called elytra. These structures are often presumed to have been a major driving force for the successful radiation of this taxon, by providing beetles with protection against a variety of harsh environmental factors. However, few studies have directly demonstrated the functional significance of the elytra against diverse environmental challenges.\u00a0We \u00a0empirically tested the function of the elytra using <em>Tribolium castaneum<\/em> (the red our beetle) as a model. We tested four categories of stress on the beetles: physical damage to hindwings, predation, desiccation, and cold shock. We found that, in all categories, the presence of elytra conferred a significant advantage compared to those beetles with their elytra experimentally removed. This work provides compelling quantitative evidence supporting the importance of beetle forewings in tolerating a variety of environmental stresses, and gives insight into how the evolution of elytra have facilitated the remarkable success of beetle radiation.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p><em>References:<\/em><\/p>\n<ul>\n<li>Linz, D.M., Hu, A.W., Sitvarin M.I, Tomoyasu, Y. Functional value of elytra under various stresses in the red flour beetle, <em>Tribolium castaneum<\/em>. Scientific Reports. 6, Article number: 34813 (2016)<span style=\"color: #993300\"> <strong><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2016-SR-Linz-Hu.pdf\" target=\"_blank\">pdf<\/a><\/strong><\/span><\/li>\n<\/ul>\n<h1><span style=\"color: #008080\">Systemic RNAi in Insects<\/span><\/h1>\n<div class=\"page\" title=\"Page 1\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-498 size-medium alignleft\" src=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2004DGE_cover-226x300.jpg\" width=\"226\" height=\"300\" srcset=\"https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2004DGE_cover-226x300.jpg 226w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2004DGE_cover-768x1018.jpg 768w, https:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2004DGE_cover-773x1024.jpg 773w\" sizes=\"auto, (max-width: 226px) 100vw, 226px\" \/><\/p>\n<p>The red flour beetle, <em>Tribolium castaneum<\/em>, offers a repertoire of experimental tools for genetic and developmental studies, including a fully annotated genome sequence, transposon-based transgenesis, and effective RNA interference (RNAi). Among these advantages, RNAi-based gene knockdown techniques are at the core of <em>Tribolium<\/em> research. <em>Tribolium\u00a0<\/em>show a robust systemic RNAi response, making it possible to perform RNAi at any life stage by simply injecting double-stranded RNA (dsRNA) into the beetle\u2019s body cavity.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<p style=\"text-align: left\">We are among the first to\u00a0establish an RNAi technique that allows us to perform gene knockdown experiments during post-embryonic stages in <em>Tribolium<\/em>. Until this study, with a few exceptions (such as the transgenic-based RNAi in <em>Drosophila<\/em>), RNAi analysis was limited to studies of embryogenesis. This method enabled us to study the molecular mechanisms underlying adult morphological diversity using <em>Tribolium<\/em> as a model system. Since then, this technique has been applied to many insects and become essential to study gene function in various insects.<\/p>\n<p style=\"text-align: left\">In addition to using RNAi as a tool, we also study\u00a0RNAi itself.\u00a0RNAi \u00a0is a highly conserved cellular defense mechanism (in which dsRNA suppresses the translation of homologous mRNA). Interestingly, in some organisms, the RNAi response can be transmitted systemically from cell to cell, a phenomenon termed &#8216;systemic RNAi&#8217;. Understanding systemic RNAi will be crucial for the application of RNAi to many other insects, which will open the possibility of functional analysis in various insects and also will provide us with the route to establish RNAi-based pest management strategies.<\/p>\n<p style=\"text-align: left\"><span style=\"text-decoration: underline\"><em>References:<\/em><\/span><\/p>\n<ul>\n<li>Linz, D.M., Clark-Hachtel, C.M., Borr\u00e0s-Castells, F., Tomoyasu, Y. Larval RNA Interference in the Red Flour Beetle, <em>Tribolium<\/em><em>castaneum<\/em>.\u00a0J. Vis. Exp. (92), e52059. (2014).<span style=\"color: #0000ff\"> <a style=\"color: #0000ff\" href=\"https:\/\/www.jove.com\/video\/52059\/larval-rna-interference-in-the-red-flour-beetle-tribolium-castaneum\" target=\"_blank\"><strong>link<\/strong><\/a><\/span><\/li>\n<li>Miyata K., Ramaseshadri P., Zhang Y., Segers G., Bolognesi R., and Tomoyasu Y. Establishing an in vivo assay system to identify components involved in environmental RNA Interference in the Western Corn Rootworm PLoS One. 9(7): e101661. (2014) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2014-PLoS-ONE-Miyata.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Miller S.C., Miyata K., Brown S.J., Tomoyasu Y.* Dissecting Systemic RNA Interference in the Red Flour Beetle <em>Tribolium castaneum<\/em>: Parameters Affecting the Efficiency of RNAi. PLoS One. 7(10):e47431 (2012) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2012-PLoS-ONE-Miller.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Miller, S.C., Brown, S.J., Tomoyasu, Y. Larval RNAi in <em>Drosophila<\/em>? Development Genes and Evolution. 218(9):505-10 (2008) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2008-Dev-Genes-Evol-Miller.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Tomoyasu Y., Miller, S.C., Tomita, S., Schoppmeier, M., Grossmann, D., Bucher, G. Exploring Systemic RNA Interference in Insects: a Genome-Wide Survey for RNAi Genes in <em>Tribolium<\/em>. Genome Biology. 17;9(1):R10 (2008) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2008_GB_Tomoyasu.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<li>Tomoyasu Y., Denell R.E. Larval RNAi in <em>Tribolium<\/em> (Coleoptera) for analyzing adult development. Development Genes and Evolution. 214(11):575-8. (2004) <span style=\"color: #993300\"><a style=\"color: #993300\" href=\"http:\/\/sites.miamioh.edu\/tomoyasulab\/files\/2017\/09\/2004-DGE-Tomoyasu.pdf\" target=\"_blank\"><strong>pdf<\/strong><\/a><\/span><\/li>\n<\/ul>\n<h1 style=\"text-align: left\"><\/h1>\n","protected":false},"excerpt":{"rendered":"<p>Diversification\u00a0of insect\u00a0wings The impressive diversity of insect wings makes them an excellent model to study the molecular basis behind morphological evolution. We\u00a0have been investigating the conserved and diverged aspects of genetic mechanisms responsible for wing development in various insects, including the fruit fly (Drosophila) and the red flour beetle (Tribolium), in order to elucidate the [&hellip;]<\/p>\n","protected":false},"author":1595,"featured_media":0,"parent":7,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"footnotes":""},"class_list":["post-405","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/pages\/405","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/users\/1595"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/comments?post=405"}],"version-history":[{"count":0,"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/pages\/405\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/pages\/7"}],"wp:attachment":[{"href":"https:\/\/sites.miamioh.edu\/tomoyasulab\/wp-json\/wp\/v2\/media?parent=405"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}