A Genome-Wide Collection of Mos1 Transposon Insertion Mutants for the C. elegans Research Community

Methods that use homologous recombination to engineer the genome of C. elegans commonly use strains carrying specific insertions of the heterologous transposon Mos1. A large collection of known Mos1 insertion alleles would therefore be of general interest to the C. elegans research community. We describe here the optimization of a semi-automated methodology for the construction of a substantial collection of Mos1 insertion mutant strains. At peak production, more than 5,000 strains were generated per month. These strains were then subject to molecular analysis, and more than 13,300 Mos1 insertions characterized. In addition to targeting directly more than 4,700 genes, these alleles represent the potential starting point for the engineered deletion of essentially all C. elegans genes and the modification of more than 40% of them. This collection of mutants, generated under the auspices of the European NEMAGENETAG consortium, is publicly available and represents an important research resource

La critique d’art à l’écran

Le film est-il à même de renouveler notre rapport aux arts plastiques ? Est-il capable, surtout, de tenir un discours critique spécifique sur les œuvres, l’histoire de l’art ou l’esthétique ? À l’intérieur du champ du « film sur l’art » auquel l’époque accorde une pleine visibilité, le propos de cet ouvrage est de configurer une zone particulière, celle des médiations cinématographiques du savoir sur l’art. Sont envisagés les films qui ouvrent un espace critique, c’est-à-dire ceux qui exhibent leur source d’énonciation ou articulent un discours argumenté à propos de l’œuvre, du medium ou de l’art en général. Quatre pistes de réflexion majeures sont abordées : capacité du cinéma à construire un regard critique sur la production artistique, à capter le geste du peintre afin de percer le secret d’un style, à représenter les musées et les publics, enfin à remettre en question le partage des hiérarchies et des genres.Can film renew our relation to the visual arts? Does film offer a specific type of critical discourse on works of art, art history or esthetics? Within the domain of “films on art” which have recently gained in visibility, the goal of this volume is to delimit the zone of exchanges between the cinema and the study of the visual arts

Distribution of <i>Mos1</i> alleles.

<p>(A) Graph showing the relationship between chromosome length (as a percentage of the whole nuclear genome) and the proportion of <i>Mos1</i> alleles per chromosome reported in a previous study <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030482#pone.0030482-Granger1" target="_blank">[5]</a>, and the 10,858 alleles obtained in the current project (black and red circles, respectively). The outliers, concerning chromosomes I and V, from the previous study are highlighted with lines. (B) Distribution of distances from one <i>Mos1</i> allele to the next, in a 5′ to 3′ direction along each chromosome. The graph shows the cumulative percentage of alleles that are separated by less than the indicated distance. (C) Concentration of <i>Mos1</i> alleles at the extreme right end of chromosome I (length 15,072,423 bp). The separation of the allele numbers indicates that almost all the alleles were generated independently, except in two cases (ttTi2276 and ttTi2284; ttTi13453 and ttTi13460), highlighted by an asterisk. This region was also preferentially targeted during the previous study as reflected by the presence of several cxTi alleles.</p

Genomic coverage of <i>Mos1</i>.

<p>Graphical representation of each <i>C. elegans</i> chromosome showing the regions of the genome that are potentially amenable to genome engineering using the publicly-available <i>Mos1</i> alleles; it is assumed that any point up to 1.5 kb away from a transposon-insertion site can be targeted. The bottom line is a magnified view of the boxed region on chromosome X.</p

Finding <i>Mos1</i> alleles with MosLocator.

<p>(A) MosLocator (<a href="http://www.ciml.univ-mrs.fr/applications/MosLocator" target="_blank">www.ciml.univ-mrs.fr/applications/MosLocator</a>) finds <i>Mos1</i> alleles using gene sequence or transcript names. For large lists of genetic gene names, the gene sequence or transcript names can be obtained using WormMart, or here, using WormBase Converter (<a href="http://www.ciml.univ-mrs.fr/applications/WB_converter" target="_blank">www.ciml.univ-mrs.fr/applications/WB_converter</a>) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030482#pone.0030482-Engelmann1" target="_blank">[15]</a>. In the example shown, the 23 <i>ptr</i> genes were used as input. (B) Screen grabs were captured to illustrate the use of MosLocator. Left panel: a list of sequence names was entered, and the search parameters were defined. Upper right panel: a display of the output for this search. Clicking on a non-zero number displayed in either of the last two columns, for example the “2” associated with the gene T21H3.2 (<i>ptr-16</i>), generates the display shown in the inset. This is a list of the 2 <i>Mos1</i> mutant alleles that are found within the gene T21H3.2. Each allele name is hyperlinked to Wormbase. (C) A partial view of the Variation report for the <i>Mos1</i> allele <i>ttTi21065</i> found on chromosome V at Wormbase (version WS225). (D) The genomic environment of the <i>ttTi21065</i> allele is displayed. The figure is a screen-grab from Wormbase.</p

Summary of <i>Mos1</i> mutant production and characterization.

<p>Summary of <i>Mos1</i> mutant production and characterization.</p

Genome-wide distribution of <i>Mos1</i> mutant alleles.

<p>Chr: chromosome.</p