Wimmer, Ernst A.

[["dc.bibliographiccitation.firstpage","4921"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA"],["dc.bibliographiccitation.lastpage","4926"],["dc.bibliographiccitation.volume","109"],["dc.contributor.author","Khadjeh, Sara"],["dc.contributor.author","Turetzek, Natascha"],["dc.contributor.author","Pechmann, Matthias"],["dc.contributor.author","Schwager, Evelyn E."],["dc.contributor.author","Wimmer, Ernst A."],["dc.contributor.author","Damen, Wim G. M."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.date.accessioned","2018-11-07T09:12:10Z"],["dc.date.available","2018-11-07T09:12:10Z"],["dc.date.issued","2012"],["dc.description.abstract","Evolution often results in morphologically similar solutions in different organisms, a phenomenon known as convergence. However, there is little knowledge of the processes that lead to convergence at the genetic level. The genes of the Hox cluster control morphology in animals. They may also be central to the convergence of morphological traits, but whether morphological similarities also require similar changes in Hox gene function is disputed. In arthropods, body subdivision into a region with locomotory appendages (\"thorax\") and a region with reduced appendages (\"abdomen\") has evolved convergently in several groups, e. g., spiders and insects. In insects, legs develop in the expression domain of the Hox gene Antennapedia (Antp), whereas the Hox genes Ultrabithorax (Ubx) and abdominal-A mediate leg repression in the abdomen. Here, we show that, unlike Antp in insects, the Antp gene in the spider Achaearanea tepidariorum represses legs in the first segment of the abdomen (opisthosoma), and that Antp and Ubx are redundant in the following segment. The down-regulation of Antp in A. tepidariorum leads to a striking 10-legged phenotype. We present evidence from ectopic expression of the spider Antp gene in Drosophila embryos and imaginal tissue that this unique function of Antp is not due to changes in the Antp protein, but likely due to divergent evolution of cofactors, Hox collaborators or target genes in spiders and flies. Our results illustrate an interesting example of convergent evolution of abdominal leg repression in arthropods by altering the role of distinct Hox genes at different levels of their action."],["dc.identifier.doi","10.1073/pnas.1116421109"],["dc.identifier.isi","000302164200046"],["dc.identifier.pmid","22421434"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/26887"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Natl Acad Sciences"],["dc.relation.issn","0027-8424"],["dc.title","Divergent role of the Hox gene Antennapedia in spiders is responsible for the convergent evolution of abdominal limb repression"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","341"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Development Genes and Evolution"],["dc.bibliographiccitation.lastpage","350"],["dc.bibliographiccitation.volume","223"],["dc.contributor.author","Schaeper, Nina D."],["dc.contributor.author","Wimmer, Ernst A."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.date.accessioned","2018-11-07T09:18:17Z"],["dc.date.available","2018-11-07T09:18:17Z"],["dc.date.issued","2013"],["dc.description.abstract","Arthropod appendages are among the most diverse animal organs and have been adapted to a variety of functions. Due to this diversity, it can be difficult to recognize homologous parts in different appendage types and different species. Gene expression patterns of appendage development genes have been used to overcome this problem and to identify homologous limb portions across different species and their appendages. However, regarding the largest arthropod group, the hexapods, most of these studies focused on members of the winged insects (Pterygota), but primitively wingless groups like the springtails (Collembola) or silverfish and allies (Zygentoma) are underrepresented. We have studied the expression of a set of appendage patterning genes in the firebrat Thermobia domestica and the white springtail Folsomia candida. The expressions of Distal-less (Dll) and dachshund (dac) are generally similar to the patterns reported for pterygote insects. Modifications of gene regulation, for example, the lack of Dll expression in the palp of F. candida mouthparts, however, point to changes in gene function that can make the use of single genes and specific expression domains problematic for homology inference. Such hypotheses should therefore not rely on a small number of genes and should ideally also include information about gene function. The expression patterns of homothorax (hth) and extradenticle (exd) in both species are similar to the patterns of crustaceans and pterygote insects, but differ from those in chelicerates and myriapods. The proximal specificity of hth thus appears to trace from a common hexapod ancestor and also provides a link to the regulation of this gene in crustaceans."],["dc.identifier.doi","10.1007/s00427-013-0449-5"],["dc.identifier.isi","000325810600001"],["dc.identifier.pmid","23873479"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28374"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1432-041X"],["dc.relation.issn","0949-944X"],["dc.title","Appendage patterning in the primitively wingless hexapods Thermobia domestica (Zygentoma: Lepismatidae) and Folsomia candida (Collembola: Isotomidae)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","53"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Development Genes and Evolution"],["dc.bibliographiccitation.lastpage","58"],["dc.bibliographiccitation.volume","219"],["dc.contributor.author","Toegel, Jane Patricia"],["dc.contributor.author","Wimmer, Ernst A."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.date.accessioned","2018-11-07T08:34:23Z"],["dc.date.available","2018-11-07T08:34:23Z"],["dc.date.issued","2009"],["dc.description.abstract","The Drosophila spineless (ss) gene is regulated downstream of the appendage gene Distal-less (Dll) and is involved in leg and antenna development. Specifically, loss of ss leads to the homeotic transformation of the arista, the distalmost antennal segment, into tarsal identity, and the loss or fusion of distal leg segments. Here we show that the ss homolog from the red flour beetle Tribolium castaneum also homeotically transforms the beetle antenna into leg, but the extent of the transformation is significantly larger than in Drosophila, as the entire antenna (except for the basal antennifer) is transformed into pretarsal, tibiotarsal, and femoral identity; i.e., the transformation comprises the Dll positive area in both appendages. We interpret the antennal phenotype in Tribolium as evidence for a more exclusive role of ss in antennal determination downstream of Dll in the beetle. By contrast, the fact that, in Drosophila ss mutants, only a small portion of the Dll positive area in the antenna is homeotically transformed indicates that Dll uses additional targets to govern the development of the other antennal segments in the fly."],["dc.identifier.doi","10.1007/s00427-008-0265-5"],["dc.identifier.isi","000261787900007"],["dc.identifier.pmid","19030876"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?goescholar/3537"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/17796"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0949-944X"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Loss of spineless function transforms the Tribolium antenna into a thoracic leg with pretarsal, tibiotarsal, and femoral identity"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","399"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Development Genes and Evolution"],["dc.bibliographiccitation.lastpage","407"],["dc.bibliographiccitation.volume","219"],["dc.contributor.author","Kittelmann, Maike"],["dc.contributor.author","Schinko, Johannes B."],["dc.contributor.author","Winkler, Marco"],["dc.contributor.author","Bucher, Gregor"],["dc.contributor.author","Wimmer, Ernst A."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.date.accessioned","2018-11-07T11:25:55Z"],["dc.date.available","2018-11-07T11:25:55Z"],["dc.date.issued","2009"],["dc.description.abstract","The genetic control of leg development is well characterized in the fly Drosophila melanogaster. These control mechanisms, however, must differ to some degree between different insect species to account for the morphological diversity of thoracic legs in the insects. The legs of the flour beetle Tribolium castaneum differ from the Drosophila legs in their developmental mode as well as in their specific morphology especially at the larval stage. In order to identify genes involved in the morphogenesis of the Tribolium larval legs, we have analyzed EGFP enhancer trap lines of Tribolium. We have identified the zfh2 gene as a novel factor required for normal leg development in Tribolium. RNA interference with zfh2 function leads to two alternative classes of leg phenotype. The loss of a leg segment boundary and the generation of ectopic outgrowths in one class of phenotype suggest a role in leg segmentation and segment growth. The malformation of the pretarsal claw in the second class of phenotype suggests a role in distal development and the morphogenesis of the claw-shaped morphology of the pretarsus. This suggests that zfh2 is involved in the regulation of an unidentified target gene in a concentration-dependent manner. Our results demonstrate that enhancer trap screens in T. castaneum have the potential to identify novel gene functions regulating specific developmental processes."],["dc.identifier.doi","10.1007/s00427-009-0303-y"],["dc.identifier.isi","000271397600002"],["dc.identifier.pmid","19760181"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?goescholar/3758"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/56738"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0949-944X"],["dc.rights.access","openAccess"],["dc.subject.ddc","570"],["dc.title","Insertional mutagenesis screening identifies the zinc finger homeodomain 2 (zfh2) gene as a novel factor required for embryonic leg development in Tribolium castaneum"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","88"],["dc.bibliographiccitation.journal","BMC Evolutionary Biology"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Schaeper, Nina D."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.contributor.author","Wimmer, Ernst A."],["dc.date.accessioned","2018-11-07T08:44:59Z"],["dc.date.available","2018-11-07T08:44:59Z"],["dc.date.issued","2010"],["dc.description.abstract","Background: The Sp-family of transcription factors are evolutionarily conserved zinc finger proteins present in many animal species. The orthology of the Sp genes in different animals is unclear and their evolutionary history is therefore controversially discussed. This is especially the case for the Sp gene buttonhead (btd) which plays a key role in head development in Drosophila melanogaster, and has been proposed to have originated by a recent gene duplication. The purpose of the presented study was to trace orthologs of btd in other insects and reconstruct the evolutionary history of the Sp genes within the metazoa. Results: We isolated Sp genes from representatives of a holometabolous insect (Tribolium castaneum), a hemimetabolous insect (Oncopeltus fasciatus), primitively wingless hexapods (Folsomia candida and Thermobia domestica), and an amphipod crustacean (Parhyale hawaienis). We supplemented this data set with data from fully sequenced animal genomes. We performed phylogenetic sequence analysis with the result that all Sp factors fall into three monophyletic clades. These clades are also supported by protein domain structure, gene expression, and chromosomal location. We show that clear orthologs of the D. melanogaster btd gene are present even in the basal insects, and that the Sp5-related genes in the genome sequence of several deuterostomes and the basal metazoans Trichoplax adhaerens and Nematostella vectensis are also orthologs of btd. Conclusions: All available data provide strong evidence for an ancestral cluster of three Sp-family genes as well as synteny of this Sp cluster and the Hox cluster. The ancestral Sp gene cluster already contained a Sp5/btd ortholog, which strongly suggests that btd is not the result of a recent gene duplication, but directly traces back to an ancestral gene already present in the metazoan ancestor."],["dc.identifier.doi","10.1186/1471-2148-10-88"],["dc.identifier.isi","000276818000002"],["dc.identifier.pmid","20353601"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5682"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/20323"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Biomed Central Ltd"],["dc.relation.issn","1471-2148"],["dc.rights","CC BY 2.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.0"],["dc.title","A clustered set of three Sp-family genes is ancestral in the Metazoa: evidence from sequence analysis, protein domain structure, developmental expression patterns and chromosomal location"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","363"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Developmental Biology"],["dc.bibliographiccitation.lastpage","376"],["dc.bibliographiccitation.volume","344"],["dc.contributor.author","Schaeper, Nina D."],["dc.contributor.author","Pechmann, Matthias"],["dc.contributor.author","Damen, Wim G. M."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.contributor.author","Wimmer, Ernst A."],["dc.date.accessioned","2018-11-07T08:40:43Z"],["dc.date.available","2018-11-07T08:40:43Z"],["dc.date.issued","2010"],["dc.description.abstract","The insect intercalary segment represents a small and appendage-less head segment that is homologous to the second antennal segment of Crustacea and the pedipalpal segment in Chelicerata, which are generally referred to as \"tritocerebral segment\" In Drosophila, the gene collier (col) has an important role for the formation of the intercalary segment Here we show that in the beetle Tribolium castaneum col is required for the activation of the segment polarity genes hedgehog (hh), engrailed (en) and wingless (wg) in the intercalary segment, and is a regulatory target of the intercalary segment specific Hox gene labial (lab) Loss of Tc col function leads to increased cell death in the intercalary segment In the milkweed bug Oncopeltus fasciatus, the loss of col function has a more severe effect in lacking the intercalary segment and also affecting the adjacent mandibular and antenna! segments By contrast, col is not expressed early in the second antennal segment in the crustacean Parhyale hawarensis or in the pedipalpal segment of the spider Achaearanea tepidariorum This suggests that the early expression of col in a stripe and its role in tritocerebral segment development is insect-specific and might correlate with the appendage-less morphology of the intercalary segment. (C) 2010 Elsevier Inc. All rights reserved."],["dc.identifier.doi","10.1016/j.ydbio.2010.05.001"],["dc.identifier.isi","000280426400032"],["dc.identifier.pmid","20457148"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19296"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Academic Press Inc Elsevier Science"],["dc.relation.issn","0012-1606"],["dc.title","Evolutionary plasticity of collier function in head development of diverse arthropods"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","427"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Development Genes and Evolution"],["dc.bibliographiccitation.lastpage","435"],["dc.bibliographiccitation.volume","219"],["dc.contributor.author","Schaeper, Nina D."],["dc.contributor.author","Prpic, Nikola-Michael"],["dc.contributor.author","Wimmer, Ernst A."],["dc.date.accessioned","2018-11-07T11:25:55Z"],["dc.date.available","2018-11-07T11:25:55Z"],["dc.date.issued","2009"],["dc.description.abstract","The genes encoding the closely related zinc finger transcription factors Buttonhead (Btd) and D-Sp1 are expressed in the developing limb primordia of Drosophila melanogaster and are required for normal growth of the legs. The D-Sp1 homolog of the red flour beetle Tribolium castaneum, Sp8 (appropriately termed Sp8/9), is also required for the proper growth of the leg segments. Here we report on the isolation and functional study of the Sp8/9 gene from the milkweed bug Oncopeltus fasciatus. We show that Sp8/9 is expressed in the developing appendages throughout development and that the downregulation of Sp8/9 via RNAi leads to antennae, rostrum, and legs with shortened and fused segments. This supports a conserved role of Sp8/9 in allometric leg segment growth. However, all leg segments including the claws are present and the expression of the leg genes Distal-less, dachshund, and homothorax are proportionally normal, thus providing no evidence for a role of Sp8/9 in appendage specification."],["dc.identifier.doi","10.1007/s00427-009-0301-0"],["dc.identifier.isi","000271397600005"],["dc.identifier.pmid","19760183"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?goescholar/3757"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/56739"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0949-944X"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","A conserved function of the zinc finger transcription factor Sp8/9 in allometric appendage growth in the milkweed bug Oncopeltus fasciatus"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]