To be or not to be a flatworm : the acoel controversy

Egger, Bernhard and Steinke, Dirk and Tarui, Hiroshi and De Mulder, Katrien and Arendt, Detlev and Borgonie, Gaëtan and Funayama, Noriko and Gschwentner, Robert and Hartenstein, Volker and Hobmayer, Bert and Hooge, Matthew and Hrouda, Martina and Ishida, Sachiko and Kobayashi, Chiyoko and Kuales, Georg and Nishimura, Osamu and Pfister, Daniela and Rieger, Reinhard and Salvenmoser, Willi and Smith, Julian and Technau, Ulrich and Tyler, Seth and Agata, Kiyokazu and Salzburger, Walter and Ladurner, Peter. (2009) To be or not to be a flatworm : the acoel controversy. PLoS ONE, Vol. 4, H. 5 , e5502.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A5252021

Downloads: Statistics Overview


Since first described, acoels were considered members of the flatworms (Platyhelminthes). However, no clear synapomorphies among the three large flatworm taxa -- the Catenulida, the Acoelomorpha and the Rhabditophora -- have been characterized to date. Molecular phylogenies, on the other hand, commonly positioned acoels separate from other flatworms. Accordingly, our own multi-locus phylogenetic analysis using 43 genes and 23 animal species places the acoel flatworm Isodiametra pulchra at the base of all Bilateria, distant from other flatworms. By contrast, novel data on the distribution and proliferation of stem cells and the specific mode of epidermal replacement constitute a strong synapomorphy for the Acoela plus the major group of flatworms, the Rhabditophora. The expression of a piwi-like gene not only in gonadal, but also in adult somatic stem cells is another unique feature among bilaterians. These two independent stem-cell-related characters put the Acoela into the Platyhelminthes-Lophotrochozoa clade and account for the most parsimonious evolutionary explanation of epidermal cell renewal in the Bilateria. Most available multigene analyses produce conflicting results regarding the position of the acoels in the tree of life. Given these phylogenomic conflicts and the contradiction of developmental and morphological data with phylogenomic results, the monophyly of the phylum Platyhelminthes and the position of the Acoela remain unresolved. By these data, both the inclusion of Acoela within Platyhelminthes, and their separation from flatworms as basal bilaterians are well-supported alternatives.
Faculties and Departments:05 Faculty of Science > Departement Umweltwissenschaften > Integrative Biologie > Evolutionary Biology (Salzburger)
UniBasel Contributors:Salzburger, Walter
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:Public Library of Science
Note:Publication type according to Uni Basel Research Database: Journal article
Related URLs:
Identification Number:
Last Modified:31 Aug 2018 06:40
Deposited On:22 Mar 2012 13:38

Repository Staff Only: item control page