La sculpture romaine en Occident

Cet ouvrage réunit les résultats de deux manifestations complémentaires  : d’une part, la table ronde intitulée «  Rendre à César  », organisée le mercredi 20 juin 2012, à Paris, au Musée du Louvre et, d’autre part, les «  Rencontres autour de la sculpture romaine conservée en France  » qui ont eu lieu du 18 au 20 octobre 2012 au Musée départemental Arles antique. La richesse des interventions lors de ces deux manifestations permet de restituer un ouvrage composé de trente-huit articles, répartis en trois parties et une conclusion. La première partie, en écho et en développement de la table ronde du Louvre, porte sur le portrait du «  César du Rhône  », aussi bien que sur «  Le portrait romain en Gaule  ». La deuxième partie publie cinq études autour des «  nouvelles techniques d’investigations scientifiques  » et présente l’analyse des matériaux des sculptures en pierre et en bronze, découvertes dans le Rhône à Arles, ainsi qu’une étude ethnoarchéologique sur les techniques de production du portrait. Enfin une troisième partie présente les «  découvertes récentes et les nouvelles recherches  », déclinées en seize études qui sont consacrées à des études de cas (Autun, Vaison-la-Romaine, Nîmes, Metz-Divodurum, Apt), ainsi qu’à des relectures novatrices de sculptures méconnues (Plouarzel, Langres, Avignonet-Lauragais, Vernègues, vallée de l’Ubaye, Besançon, Lyon). Robert Turcan signe la conclusion. Ainsi, «  La sculpture romaine en Occident. Nouveaux regards   » reflète la variété et l’intérêt des questionnements actuels dans ce domaine

Alary muscles and TARMs, a novel type of striated muscles maintaining internal organs positions

International audienc

Improving the quality of micro-nanostructures replication on a polymer surface to confer new functional properties

International audienc

Drosophila melanogaster Hox transcription factors access the RNA polymerase II machinery through direct homeodomain binding to a conserved motif of mediator subunit Med19

International audienceHox genes in species across the metazoa encode transcription factors (TFs) containing highly-conserved homeodomains that bind target DNA sequences to regulate batteries of developmental target genes. DNA-bound Hox proteins, together with other TF partners, induce an appropriate transcriptional response by RNA Polymerase II (PolII) and its associated general transcription factors. How the evolutionarily conserved Hox TFs interface with this general machinery to generate finely regulated transcriptional responses remains obscure. One major component of the PolII machinery, the Mediator (MED) transcription complex, is composed of roughly 30 protein subunits organized in modules that bridge the PolII enzyme to DNA-bound TFs. Here, we investigate the physical and functional interplay between Drosophila melanogaster Hox developmental TFs and MED complex proteins. We find that the Med19 subunit directly binds Hox homeodomains, in vitro and in vivo. Loss-of-function Med19 mutations act as dose-sensitive genetic modifiers that synergistically modulate Hox-directed developmental outcomes. Using clonal analysis, we identify a role for Med19 in Hox-dependent target gene activation. We identify a conserved, animal-specific motif that is required for Med19 homeodomain binding, and for activation of a specific Ultrabithorax target. These results provide the first direct molecular link between Hox homeodomain proteins and the general PolII machinery. They support a role for Med19 as a PolII holoenzyme-embedded "co-factor" that acts together with Hox proteins through their homeodomains in regulated developmental transcription

Genome-wide mapping of collier In vivo binding sites highlights its hierarchical position in different transcription regulatory networks

Collier, the single Drosophila COE (Collier/EBF/Olf-1) transcription factor, is required in several developmental processes, including head patterning and specification of muscle and neuron identity during embryogenesis. To identify direct Collier (Col) targets in different cell types, we used ChIP-seq to map Col binding sites throughout the genome, at mid-embryogenesis. In vivo Col binding peaks were associated to 415 potential direct target genes. Gene Ontology analysis revealed a strong enrichment in proteins with DNA binding and/or transcription-regulatory properties. Characterization of a selection of candidates, using transgenic CRM-reporter assays, identified direct Col targets in dorso-lateral somatic muscles and specific neuron types in the central nervous system. These data brought new evidence that Col direct control of the expression of the transcription regulators apterous and eyes-absent (eya) is critical to specifying neuronal identities. They also showed that cross-regulation between coland eya in muscle progenitor cells is required for specification of muscle identity, revealing a new parallel between the myogenic regulatory networks operating in Drosophila and vertebrates. Col regulation of eya, both in specific muscle and neuronal lineages, may illustrate one mechanism behind the evolutionary diversification of Col biological roles

Col direct control of <i>eya</i> expression in Ap neurons.

<p>(A) Annotation of the Col peaks in <i>eya</i>, same representation as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133387#pone.0133387.g002" target="_blank">Fig 2A</a>; 24 kb of the <i>eya</i> genomic region are shown (Chr2L: 6.524.500–6.548.500); the summits of the two ChIP-Col peaks are numbered 1 and 2. (B, C) <i>eya_</i>Col (GFP) expression in the dAp (yellow arrow) and Tv1-Tv4 neurons (white arrow) in stage 16 embryos, ventral view. (C) Close up view of abdominal segments, showing the specific overlap between Col (red) and <i>eya_</i>Col (green) in the dAp (yellow arrow) and Tv1 neurons (white arrow). (D, E) <i>eya_</i>Col^mut expression is lost in dAP neurons and reduced in TV neurons. (F, G) Mutation of the Col binding site 2 (G), but not site 1 (F) eliminates <i>eya_</i>Col (RFP) expression in dAp neurons (yellow arrow).</p

Col control of <i>cnc</i> and <i>Ama</i> expression in the head.

<p>(A) Annotation of the Col peak in <i>cnc</i>, adapted from <i>Gene Browser</i> (GEO submission GSE67805). 39,5 kb of <i>cnc</i> genomic region are shown (Chr3R: 19.009.000–19.048.500) with the Flybase gene annotation indicated by bars (transcribed regions) and intervening blue lines (introns). Black arrows indicate the direction of transcription of <i>cnc</i> and <i>fuzzy onions</i> (<i>fzo</i>), <i>inwardly rectifying potassium channel 1</i> (<i>Irk1</i>). The <i>cnc</i> transcripts coding for the protein isoforms CncA and CncB are indicated. ChIP-seq data for Col (green) substracted from HA (mock) data (red) are shown on the bottom. The Col Dam-ID binding regions [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0133387#pone.0133387.ref059" target="_blank">59</a>] are indicated by yellow bars, top line. The summit of the ChIP-Col peak identified by SISSRs and position of the Col binding site(s) identified by MEME are indicated by blue and violet lines, respectively; the position of <i>cnc_</i>Col is represented by a black box; scale is indicated. (B-D) Ventral anterior views of stage 11 embryos. (B) Overlap between <i>cnc_</i>Col (GFP, green) and Col (red) expression in the HL (white arrow). (C) <i>cnc_</i>Col and (D) <i>cnc_</i>Col^mut mRNA expression, showing down-regulation of <i>cnc_</i>Col^mut in the mandibular segment (open arrow). (E,F) <i>Ama</i>_Col, (G,H) <i>Ama</i>_Col^mut expression in stage 10 (E,G) and 11 (F,H) embryos. HL <i>Ama</i>_Col expression (arrow) is lost in <i>Ama</i>_Col^mut (open arrow). (I, J) Overlap between <i>Ama</i> (red), Col (blue), and <i>col</i>2.6–0.9moeGFP (green) expression in the HL (white arrow) in stage 11 wt (I), and <i>col</i>^<i>1</i> mutant embryos (J). Separate signals for <i>Ama</i>, GFP (I, J) and Col (inset in I, left panel) are shown in black and white. <i>Ama</i> expression is specifically lost in the HL in <i>col</i>^<i>1</i> mutants. The asterisk in C, D, F, H, J indicates <i>Ama</i> and <i>cnc</i> expression independent on Col.</p

Candidate Col direct targets and linked CRMs.

<p>n.d.: not detected</p><p>Candidate Col direct targets and linked CRMs.</p