caa a22 4500 445821019 CHVBK 20190327083712.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s00239-012-9483-6 doi (NATIONALLICENCE)springer-10.1007/s00239-012-9483-6 Molecular Characterization of Two Endothelin Pathways in East African Cichlid Fishes [Elektronische Daten] [Eveline Diepeveen, Walter Salzburger] The adaptive radiations of cichlid fishes in East Africa have been associated with the acquisition of evolutionary novelties as well as the ecological opportunities existing in the East African Great lakes. Two remarkable evolutionary innovations are the pharyngeal jaw apparatus, found in all cichlid species, and the anal fin egg-spots of mouthbrooding cichlids. Based on their conserved functions during the development of both the jaw apparatus and pigmentation, the endothelin ligands and receptors form a putative link between these naturally and sexually selected traits. Here we study the evolutionary history of four members of two endothelin pathways (Edn1/EdnrAa and Edn3b/EdnrB1a) to elucidate their possible roles during the evolution and development of key innovations in East African cichlids species. The analyses performed on partial sequences (ca. 6,000bp per taxon) show that all four endothelin family members evolved under purifying selection, although both ligands are characterized by an accelerated rate of protein evolution in comparison to the receptors. In accordance with earlier findings, we show that the mature protein sequence of Edn1 and Edn3 are highly conserved, also in cichlids, whereas the preproendothelin parts are variable indicating relaxed selective constraints. In the receptors, nonsynonymous substitutions were mainly found in the ligand-binding domains suggesting functional divergence. Gene expression assays with Real-Time PCR indeed reveal that the two studied endothelin pathways are expressed in the cichlid pharyngeal jaw and in the haplochromine egg-spot (among other pigment-cell containing tissues), suggesting their involvement during morphogenesis of naturally and sexually selected traits in cichlids. Springer Science+Business Media, LLC, 2012 Endothelin receptor nationallicence Pigmentation nationallicence Pharyngeal jaw nationallicence Neural crest nationallicence Key innovation nationallicence Molecular evolution nationallicence Diepeveen Eveline Zoological Institute, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland aut Salzburger Walter Zoological Institute, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland aut Journal of Molecular Evolution Springer-Verlag 73/5-6(2011-12-01), 355-368 0022-2844 73:5-6<355 2011 73 239 https://doi.org/10.1007/s00239-012-9483-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00239-012-9483-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Diepeveen Eveline Zoological Institute, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland aut NATIONALLICENCE 700 1- Salzburger Walter Zoological Institute, University of Basel, Vesalgasse 1, 4051, Basel, Switzerland aut NATIONALLICENCE 773 0- Journal of Molecular Evolution Springer-Verlag 73/5-6(2011-12-01), 355-368 0022-2844 73:5-6<355 2011 73 239 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer