caa a22 4500 475768140 CHVBK 20180406123612.0 cr unu---uuuuu 170329e20000901xx s 000 0 eng 10.1007/s004270000087 doi (NATIONALLICENCE)springer-10.1007/s004270000087 Amphicoup-TF, a nuclear orphan receptor of the lancelet Branchiostoma floridae , is implicated in retinoic acid signalling pathways [Elektronische Daten] [M.-C. Langlois, J.-M. Vanacker, N. D. Holland, H. Escriva, C. Queva, V. Laudet, L. Z. Holland] Abstract : In vertebrates, the orphan nuclear receptors of the COUP-TF group function as negative transcriptional regulators that inhibit the hormonal induction of target genes mediated by classical members of the nuclear hormone superfamily, such as the retinoic acid receptors (RARs) or the thyroid hormone receptors (TRs). To investigate the evolutionary conservation of the roles of COUP-TF receptors as negative regulators in the retinoid and thyroid hormone pathways, we have characterized AmphiCOUP-TF, the homologue of COUP-TFI and COUP-TFII, in the chordate amphioxus (Branchiostoma floridae), the closest living invertebrate relative of the vertebrates. Electrophoretic mobility shift assays (EMSA) showed that AmphiCOUP-TF binds to a wide variety of response elements, as do its vertebrate homologues. Furthermore, AmphiCOUP-TF is a transcriptional repressor that strongly inhibits retinoic acid-mediated transactivation. In situ hybridizations revealed expression of AmphiCOUP-TF in the nerve cord of late larvae, in a region corresponding to hindbrain and probably anterior spinal cord. Although the amphioxus nerve cord appears unsegmented at the gross anatomical level, this pattern reflects segmentation at the cellular level with stripes of expressing cells occurring adjacent to the ends and the centers of each myotomal segment, which may include visceral motor neurons and somatic motor neurons respectively, among other cells. A comparison of the expression pattern of AmphiCOUP-TF with those of its vertebrate homologues, suggests that the roles of COUP-TF in patterning of the nerve cord evolved prior to the split between the amphioxus and vertebrate lineages. Furthermore, in vitro data also suggest that Amphi-COUP-TF acts as a negative regulator of signalling by other nuclear receptors such as RAR, TR or ER. Springer-Verlag Berlin Heidelberg, 2000 Key words Amphioxus nationallicence Cephalochordate nationallicence Nuclear hormone receptors nationallicence COUP-TF nationallicence Transcription factors nationallicence Langlois M.-C UMR 319 du CNRS, Institut de Biologie de Lille, Institut Pasteur, 1 rue Calmette, 59019 Lille Cedex, France, FR aut Vanacker J.-M UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut Holland N. D. Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0202, USA, US aut Escriva H. UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut Queva C. Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, 1100 Fairview Avenue North, WA 98109-1024, USA, US aut Laudet V. UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut Holland L. Z. Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0202, USA, US aut https://doi.org/10.1007/s004270000087 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004270000087 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Langlois M.-C UMR 319 du CNRS, Institut de Biologie de Lille, Institut Pasteur, 1 rue Calmette, 59019 Lille Cedex, France, FR aut NATIONALLICENCE 700 1- Vanacker J.-M UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut NATIONALLICENCE 700 1- Holland N. D. Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0202, USA, US aut NATIONALLICENCE 700 1- Escriva H. UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut NATIONALLICENCE 700 1- Queva C. Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, 1100 Fairview Avenue North, WA 98109-1024, USA, US aut NATIONALLICENCE 700 1- Laudet V. UMR 49 du CNRS, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France, FR aut NATIONALLICENCE 700 1- Holland L. Z. Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0202, USA, US aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer