Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
EXOSC10 is a catalytic subunit of the exosome that processes biologically active transcripts, degrades aberrant mRNAs and targets certain long non-coding RNAs (lncRNAs). The yeast orthologue Rrp6 is required for efficient growth and gametogenesis, and becomes unstable during meiosis. However, nothing is known about the localization, stability and function of EXOSC10 in the rodent male germline. We detect the protein in nucleoli and the cytoplasm of mitotic and meiotic germ cells, and find that it transiently associates with the XY body, a structure targeted by meiotic sex chromosome inactivation (MSCI). Finally, EXOSC10 becomes unstable at later stages of gamete development. To determine Exosc10's meiotic function, we inactivated the gene specifically in male germ cells using cre recombinase controlled by Stra8 or Ddx4/Vasa promoters. Mutant mice have small testes, show impaired germ cell differentiation and are subfertile. Our results demonstrate that EXOSC10 is post-translationally regulated in germ cells, associate the protein with epigenetic chromosome silencing, and reveal its essential role in germ cell growth and development.
ISSN: 2045-2322

hal-01647082
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01647082
DOI : 10.1038/s41598-017-14643-y
PUBMED : 29118343

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The extracellular signal-regulated kinase (ERK)1/2 mitogen-activated protein (MAP) kinase pathway has been involved in the positive and negative regulation of cell proliferation. Upon mitogen stimulation, ERK1/ERK2 activation is necessary for G1- to S-phase progression whereas when hyperactived, this pathway could elicit cell cycle arrest. The mechanisms involved are not fully elucidated but a kinase-independent function of ERK1/2 has been evidenced in the MAPK-induced growth arrest. Here, we show that p70S6K, a central regulator of protein biosynthesis, is essential for the cell cycle arrest induced by overactivation of ERK1/2. Indeed, whereas MEK1 silencing inhibits cell cycle progression, we demonstrate that active mutant form of MEK1 or MEK2 triggers a G1 phase arrest by stimulating an activation of p70S6K by ERK1/2 kinases. Silencing of ERK1/2 activity by shRNA efficiently suppresses p70S6K phosphorylation on Thr421/Ser424 and S6 phosphorylation on Ser240/244 as well as p21 expression, but these effects can be partially reversed by the expression of kinase-dead mutant form of ERK1 or ERK2. In addition, we demonstrate that the kinase p70S6K modulates neither the p21 gene transcription nor the stability of the protein but enhances the translation of the p21 mRNA. In conclusion, our data emphasizes the importance of the translational regulation of p21 by the MEK1/2-ERK1/2-p70S6K pathway to negatively control the cell cycle progression. J. Cell. Physiol. 229: 903-915, 2014. © 2013 Wiley Periodicals, Inc.
ISSN: 0021-9541

hal-01061238
https://hal.archives-ouvertes.fr/hal-01061238
https://hal.archives-ouvertes.fr/hal-01061238/document
https://hal.archives-ouvertes.fr/hal-01061238/file/MEK12_OveractivationArticle_GUEGAN_JCP_2014.pdf
DOI : 10.1002/jcp.24521

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
BOI1 and BOI2 are paralogs important for the actin cytoskeleton andpolar growth. BOI1 encodes a meiotic transcript isoform with an extended5-untranslated region predicted to impair protein translation. It is,however, unknown how the isoform is repressed during mitosis, and ifBoi1 is present during sporulation. By interpreting microarray data fromMATa cells, MATa/ cells, a starving MAT/ control, and a meiosis-impairedrrp6 mutant, we classified BOI1's extended isoform as earlymeiosis-specific. These results were confirmed by RNA-Sequencing, andextended by a 5-RACE assay and Northern blotting, showing that meioticcells induce the long isoform while the mitotic isoform remainsdetectable during meiosis. We provide evidence via motif predictions, anin vivo binding assay and genetic experiments that the Rpd3/Sin3/Ume6histone deacetylase complex, which represses meiotic genes duringmitosis, also prevents the induction of BOI1's 5-extended isoform inmitosis by direct binding of Ume6 to its URS1 target. Finally, we findthat Boi1 protein levels decline when cells switch from fermentation torespiration and sporulation. The histone deacetylase Rpd3 is conserved,and eukaryotic genes frequently encode transcripts with variable 5-UTRs.Our findings are therefore relevant for regulatory mechanisms involvedin the control of transcript isoforms in multi-cellular organisms.
ISSN: 0950-382X

hal-01122120
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122120
DOI : 10.1111/mmi.12976
PUBMED : 25708805

Éditeur(s) : HAL CCSD Taylor & Francis
Résumé : International audience
The retroviral genome consists of an intron-containing transcript that has essential cytoplasmic functions in the infected cell. This viral transcript can escape splicing, circumvent the nuclear checkpoint mechanisms and be transported to the cytoplasm by hijacking the host machinery. Once in the cytoplasm, viral unspliced RNA acts as mRNA to be translated and as genomic RNA to be packaged into nascent viruses. The murine leukemia virus (MLV) is among the first retroviruses discovered and is classified as simple Retroviridae due to its minimal encoding capacity. The oncogenic and transduction abilities of MLV are extensively studied, whereas surprisingly the crucial step of its nuclear export has remained unsolved until 2014. Recent work has revealed the recruitment by MLV of the cellular NXF1/Tap-dependent pathway for export. Unconventionally, MLV uses of Tap to export both spliced and unspliced viral RNAs. Unlike other retroviruses, MLV does not harbor a unique RNA signal for export. Indeed, multiple sequences throughout the MLV genome appear to promote export of the unspliced MLV RNA. We review here the current understanding of the export mechanism and highlight the determinants that influence MLV export. As the molecular mechanism of MLV export is elucidated, we will gain insight into the contribution of the export pathway to the cytoplasmic fate of the viral RNA
ISSN: 1547-6286

hal-01217990
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01217990
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01217990/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01217990/file/Insights%20into%20the%20nuclear%20export%20of%20murine%20leukemia%20virus%20intron-containing%20RNA.pdf
DOI : 10.1080/15476286.2015.1065375

Éditeur(s) : HAL CCSD Taylor & Francis
Résumé : International audience
The origin of replication complex subunit ORC1 is important for DNA replication. The gene is known to encode a meiotic transcript isoform (mORC1) with an extended 5′-untranslated region (5′-UTR), which was predicted to inhibit protein translation. However, the regulatory mechanism that controls the mORC1 transcript isoform is unknown and no molecular biological evidence for a role of mORC1 in negatively regulating Orc1 protein during gametogenesis is available. By interpreting RNA profiling data obtained with growing and sporulating diploid cells, mitotic haploid cells, and a starving diploid control strain, we determined that mORC1 is a middle meiotic transcript isoform. Regulatory motif predictions and genetic experiments reveal that the activator Ndt80 and its middle sporulation element (MSE) target motif are required for the full induction of mORC1 and the divergently transcribed meiotic SMA2 locus. Furthermore, we find that the MSE-binding negative regulator Sum1 represses both mORC1 and SMA2 during mitotic growth. Finally, we demonstrate that an MSE deletion strain, which cannot induce mORC1, contains abnormally high Orc1 levels during post-meiotic stages of gametogenesis. Our results reveal the regulatory mechanism that controls mORC1, highlighting a novel developmental stage-specific role for the MSE element in bi-directional mORC1/SMA2 gene activation, and correlating mORC1 induction with declining Orc1 protein levels. Because eukaryotic genes frequently encode multiple transcripts possessing 5′-UTRs of variable length, our results are likely relevant for gene expression during development and disease in higher eukaryotes. © 2016 Taylor & Francis Group, LLC.
ISSN: 1547-6286

hal-01367153
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01367153
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01367153/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01367153/file/Ndt80%20activates%20the%20meiotic%20ORC1%20transcript.pdf
PUBMEDCENTRAL : PMC5013992

Éditeur(s) : HAL CCSD Oxford University Press
Résumé : International audience
It was recently reported that the sizes of many mRNAs change when budding yeast cells exit mitosis and enter the meiotic differentiation pathway. These differences were attributed to length variations of their untranslated regions. The function of UTRs in protein translation is well established. However, the mechanism controlling the expression of distinct transcript isoforms during mitotic growth and meiotic development is unknown. In this study, we order developmentally regulated transcript isoforms according to their expression at specific stages during meiosis and gametogenesis, as compared to vegetative growth and starvation. We employ regulatory motif prediction, in vivo protein-DNA binding assays, genetic analyses and monitoring of epigenetic amino acid modification patterns to identify a novel role for Rpd3 and Ume6, two components of a histone deacetylase complex already known to repress early meiosis-specific genes in dividing cells, in mitotic repression of meiosis-specific transcript isoforms. Our findings classify developmental stage-specific early, middle and late meiotic transcript isoforms, and they point to a novel HDAC-dependent control mechanism for flexible transcript architecture during cell growth and differentiation. Since Rpd3 is highly conserved and ubiquitously expressed in many tissues, our results are likely relevant for development and disease in higher eukaryotes.
ISSN: 0305-1048

Droits : http://creativecommons.org/licenses/by/
hal-01122128
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01122128/file/The%20conserved%20histone%20deacetylase.pdf
DOI : 10.1093/nar/gku1185

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Although many studies reported mechanisms involved in the positive regulation of estrogens (E2) target genes, very little is known concerning the repressive effect of E2. In this study, we explored the molecular mechanisms by which E2 regulates CXCR7 expression in breast cancer cells. Our results show that E2-mediated down-regulation of CXCR7 occurs at the transcriptional level as demonstrated using actinomycin D and requires estrogen receptor alpha (ERα). In addition, CXCR7 is a primary ERα-target gene because the effect of E2 does not require the synthesis of an intermediary protein as revealed by the translational inhibitor cycloheximide treatment. Using an inhibitor of the NFκB pathway and chromatin immunoprecipitation assays, we demonstrated that NFκB is necessary for the high expression of CXCR7 gene and is recruited to the proximal promoter of the CXCR7 gene. Interestingly, the chromatin immunoprecipitation analyses also showed that E2-treatment significantly prevented the recruitment of NFκB to the promoter. Altogether, our results demonstrate that E2, through ERα, directly down-regulates CXCR7 expression by interfering with NFκB transcription factor at the promoter level.
ISSN: 0006-291X

inserm-00808966
http://www.hal.inserm.fr/inserm-00808966
DOI : 10.1016/j.bbrc.2013.01.050
PUBMED : 23352615

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Thermal acclimation drastically alters thermotolerance of ectotherms, but the mechanisms determining this plastic response are not fully understood. The present study investigates the proteomic response (2D-DIGE) of adult Drosophila melanogaster acclimated at 11, 25 or 31 C. As expected 11 C-acclimation improved cold tolerance and 31 C-acclimation improved heat tolerance. We hypothesized that the marked organismal responses to acclimation could be detected at the proteomic level assuming that changes in the abundance of specific proteins are linked to the physiological changes underlying the phenotypic response. The 31 C-acclimated flies displayed a particular divergent proteomic profile where molecular chaperones made up a large number of the proteins that were modulated during heat acclimation. Many other proteins showed significant modulation during acclimation including proteins involved in iron ion and cell redox homeostasis, carbohydrate and energy metabolism, chromatin remodeling and translation, and contractile machinery. Interestingly the changes in protein abundance were often unrelated to transcriptional activity of the genes coding for the proteins, except for the most strongly expressed proteins (e.g. Hsp70). The 11 C-acclimation evoked weak proteomic response despite the marked effect on the organismal phenotype. Thus the acquired cold tolerance observed here may involve regulatory process such as posttranslational regulation rather than de novo protein synthesis.
ISSN: 0965-1748

hal-00826939
https://hal.archives-ouvertes.fr/hal-00826939
DOI : 10.1016/j.ibmb.2013.01.006
PUBMED : 23416132

Éditeur(s) : HAL CCSD
Résumé : International audience
In addition to soluble factors, mechanical constraints and extracellular matrix stiffness are important regulators of cell fate that are mediated by cytoskeletal modifications. The EMT (epithelial-mesenchymal transition) that occurs during normal development and malignant progression is a typical example of the phenotypic switch associated with profound actin remodelling and changes in gene expression. For instance, actin dynamics control motile cell functions in EMT, in part, through regulating the subcellular localization of the myocardin-related transcription factor MKL1 (megakaryoblastic leukaemia translocation 1), a co-activator of SRF (serum-responsive factor). In the present paper, we show that MKL1 participates also to the control of the cellular switch between growth and quiescence. Experimental disconnection between MKL1 and G-actin (globular actin), by using an MKL1 mutant or enhancing the F (filamentous)-/G-actin ratio, generates a widely open chromatin state and a global increase in biosynthetic activity, classically associated with cell growth. Conversely, G-actin accumulation favours nuclear condensation and cell quiescence. These large-scale chromatin changes rely upon extensive histone modifications, exemplified by that of H3K9 (H3 Lys9) shifting from trimethylation, a heterochromatin mark, to acetylation, a mark of euchromatin. The present study provides the first evidence for a global reversible hetero/euchromatinization phenomenon triggered by the actin/MKL1 signalling pathway.
The Biochemical Journal

hal-01063933
https://hal.archives-ouvertes.fr/hal-01063933
DOI : 10.1042/BJ20131240
PUBMED : 24762104

Éditeur(s) : HAL CCSD Sidestone Press
Résumé : International audience
In 2006, an INRAP team led by T. Romon proceeded to search the Amerindian dump of the Gare Maritime in Basse-Terre. An important collection of ceramics there was discovered and then examined by Mr. Hildebrand. The results made possible to assign the occupation to subseries of old huecan and Cedrosan Saladoid.As part of a master’s degree research in archaeology, a study of sets of this pottery was considered a new approach. The latter, inspired by an analysis ofJ. Van Berg on the Rubanné ceramics, can be called structural. Indeed, the search for elementary motifs in this type of decoration, said abstract, can reconstruct it by studying how the motifs fit together. We can compare the motifs to a panel of vocabulary, which combine according to rules of "grammar" defined.This method thus relies on a precise statistical analysis that highlights thecombinatorial rules by inserting an additional factor: that of the various decorating techniques (etching, engraving, painting, modeling).These rules can be translated simply by notions of "presence / absence" or by incorporating a notion of frequency depending on the level of complexity of the decoration. This is the number of motifs creating the set. We call this the set of one or two motifs for simple associations or of four or five motifs for complex sets.The objective of this study is to express an early hypothesis, which would tend to reveal the existence or not of a specific hierarchy of elementary motifs depending on various factors such as complexity of the set or the technique used in both huecan and Cedrosan subseries.
En 2006, un equipo del INRAP dirigido por T. Romon procedió a la excavación del vertedero amerindio de la Estación Marítima en Bsse-terre. Una importante colección de cerámica fue puesta allí al día y a continuación estudiada por el Sr. Hildebrand. Los resultados obtenidos permitieron de asignar esta ocupación a las subseries del Saladoïde huecan y cedrosan antiguos.En el marco de un curso de posgrado en arqueologia, se previo un estudio de los decorados de este conjunto de cerámica según un nuevo enfoque. Esta última, inspirada en un análisis realizado por J. Van Berg, en la cerámica Rubannée,se puede llamar estructural. En efecto, la búsqueda de los motivos elementales en este tipo de decorado, dicho abstracto, permiten reconstruirlo estudiando la forma en que los motivos se arreglan. Podemos comparar los motivos a un cuadro de vocabulario que se combina según normas “gramaticales” definidas.Este método se basa, pues en un análisis de estadística precisa que pone de relieve las reglas combinatorias mediante la inserción de un factor adicional: la delas diferentes técnicas de decoración (aguafuerte, grabado, pintura, modelado).Estas normas pueden traducirse simplemente en conceptos de “presencia/ausencia” o incorporando un concepto de frecuencia según el nivel de complejidad del decorado. Este último corresponde entre motivos que crean el decorado. Hablamos entonces de decorado a unos o dos motivos para las asociaciones simples o a cuatro o cinco motivos para los decorados complejos.El objetivo de este estudio es de emitir un principio de hipótesis que tendería a revelar la existencia, o no, de una jerarquía específica de los motivos elementales en función de los distintos factores, como la complejidad del decorado o la técnica utilizada, en las dos subseries huecan y cedrosan
En 2006, une équipe de l'INRAP dirigée par T. Romon procéda à la fouille du dépotoir amérindien de la Gare Maritime à Basse-Terre. Une importante collection de céramique y fut mise au jour et ensuite étudiée par M. Hildebrand. Les résultats obtenus permirent d'attribuer cette occupation aux sous-séries du Saladoïde huecan et cedrosan ancien. Dans le cadre d'un master en archéologie, une étude des décors de cet ensemble céramique fut envisagée selon une nouvelle approche. Cette dernière, inspirée d'une analyse effectuée par J. Van Berg sur la céramique du Rubané, peut être qualifiée de structurale. En effet, la recherche des motifs élémentaires dans ce type de décor, dit abstrait, permet de le reconstruire en étudiant la façon dont les motifs s'agencent. Nous pouvons comparer les motifs à un panel de vocabulaire qui se combine selon des règles « grammaticales » définies.Cette méthode s'appuie ainsi sur une analyse statistique précise qui met en exergue les règles combinatoires en insérant un facteur supplémentaire : celui des différentes techniques de décoration (gravure, incision, peinture, modelage). Ces règles peuvent se traduire simplement par des notions de « présence / absence » ou bien en incorporant une notion de fréquence selon le niveau de complexité du décor. Ce dernier correspond au nombre de motifs créant le décor. Nous parlons alors de décor à un ou deux motifs pour les associations simples ou bien à quatre ou cinq motifs pour les décors complexes. L'objectif de cette étude est d'émettre un début d’hypothèse qui tendrait à révéler l'existence, ou non, d'une hiérarchie spécifique des motifs élémentaires en fonction des différents facteurs, comme la complexité du décor ou la technique utilisée, chez les deux sous-séries huecanes et cedrosanes.
Archéologie Caraïbe

Droits : info:eu-repo/semantics/OpenAccess
ISBN : 978-90-8890-291-8
halshs-01140826
https://halshs.archives-ouvertes.fr/halshs-01140826
https://halshs.archives-ouvertes.fr/halshs-01140826/document
https://halshs.archives-ouvertes.fr/halshs-01140826/file/Honore%20%26%20Berard%202014%20-%20Etude%20analytique%20des%20decors%20ceramiques%20du%20site%20de%20la%20Gare%20Maritime.pdf

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
The regulatory mechanisms involved in the acquisition of thermal tolerance are unknown in insects. Reversible phosphorylation is a widespread post-translational modification that can rapidly alter proteins function(s). Here, we conducted a large-scale comparative screening of phosphorylation networks in adult Drosophila flies that were cold-acclimated versus control. Using a modified SIMAC method followed by a multiple MS analysis strategy, we identified a large collection of phosphopeptides (about 1600) and phosphoproteins (about 500) in both groups, with good enrichment efficacy (80%). The saturation curves from the four biological replicates revealed that the phosphoproteome was rather well covered under our experimental conditions. Acclimation evoked a strong phosphoproteomic signal characterized by large sets of unique and differential phosphoproteins. These were involved in several major GO superclusters of which cytoskeleton organization, positive regulation of transport, cell cycle, and RNA processing were particularly enriched. Data suggest that phosphoproteomic changes in response to acclimation were mainly localized within cytoskeletal network, and particularly within microtubule associated complexes. This study opens up novel research avenues for exploring the complex regulatory networks that lead to acquired thermal tolerance.
ISSN: 2045-2322

hal-01532256
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01532256
DOI : 10.1038/s41598-017-01974-z
PUBMED : 28490779

Éditeur(s) : HAL CCSD
Résumé : International audience
Spermatogenesis is a highly sophisticated process involved in the transmission of genetic heritage. It includes halving ploidy, repackaging of the chromatin for transport, and the equipment of developing spermatids and eventually spermatozoa with the advanced apparatus (e.g., tightly packed mitochondrial sheat in the mid piece, elongating of the tail, reduction of cytoplasmic volume) to elicit motility once they reach the epididymis. Mammalian spermatogenesis is divided into three phases. In the first the primitive germ cells or spermatogonia undergo a series of mitotic divisions. In the second the spermatocytes undergo two consecutive divisions in meiosis to produce haploid spermatids. In the third the spermatids differentiate into spermatozoa in a process called spermiogenesis. Paracrine, autocrine, juxtacrine, and endocrine pathways all contribute to the regulation of the process. The array of structural elements and chemical factors modulating somatic and germ cell activity is such that the network linking the various cellular activities during spermatogenesis is unimaginably complex. Over the past two decades, advances in genomics have greatly improved our knowledge of spermatogenesis, by identifying numerous genes essential for the development of functional male gametes. Large-scale analyses of testicular function have deepened our insight into normal and pathological spermatogenesis. Progress in genome sequencing and microarray technology have been exploited for genome-wide expression studies, leading to the identification of hundreds of genes differentially expressed within the testis. However, although proteomics has now come of age, the proteomics-based investigation of spermatogenesis remains in its infancy. Here, we review the state-of-the-art of large-scale proteomic analyses of spermatogenesis, from germ cell development during sex determination to spermatogenesis in the adult. Indeed, a few laboratories have undertaken differential protein profiling expression studies and/or systematic analyses of testicular proteomes in entire organs or isolated cells from various species. We consider the pros and cons of proteomics for studying the testicular germ cell gene expression program. Finally, we address the use of protein datasets, through integrative genomics (i.e., combining genomics, transcriptomics, and proteomics), bioinformatics, and modelling.
Systems Biology in Reproductive Medicine

hal-00877749
https://hal.archives-ouvertes.fr/hal-00877749
DOI : 10.3109/19396368.2012.691943
PUBMED : 22788530

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BackgroundTo date, all studies conducted on breast cancer diagnosis have focused on the expression of the full-length 66-kDa estrogen receptor alpha (ERα66). However, much less attention has been paid to a shorter 46-kDa isoform (ERα46), devoid of the N-terminal region containing the transactivation function AF-1. Here, we investigated the expression levels of ERα46 in breast tumors in relation to tumor grade and size, and examined the mechanism of its generation and its specificities of coregulatory binding and its functional activities.MethodsUsing approaches combining immunohistochemistry, Western blotting, and proteomics, antibodies allowing ERα46 detection were identified and the expression levels of ERα46 were quantified in 116 ERα-positive human breast tumors. ERα46 expression upon cellular stress was studied, and coregulator bindings, transcriptional, and proliferative response were determined to both ERα isoforms.ResultsERα46 was expressed in over 70% of breast tumors at variable levels which sometimes were more abundant than ERα66, especially in differentiated, lower-grade, and smaller-sized tumors. We also found that ERα46 can be generated via internal ribosome entry site-mediated translation in the context of endoplasmic reticulum stress. The binding affinities of both unliganded and fully-activated receptors towards co-regulator peptides revealed that the respective potencies of ERα46 and ERα66 differ significantly, contributing to the differential transcriptional activity of target genes to 17β estradiol (E2). Finally, increasing amounts of ERα46 decrease the proliferation rate of MCF7 tumor cells in response to E2.ConclusionsWe found that, besides the full-length ERα66, the overlooked ERα46 isoform is also expressed in a majority of breast tumors. This finding highlights the importance of the choice of antibodies used for the diagnosis of breast cancer, which are able or not to detect the ERα46 isoform. In addition, since the function of both ERα isoforms differs, this work underlines the need to develop new technologies in order to discriminate ERα66 and ERα46 expression in breast cancer diagnosis which could have potential clinical relevance.
ISSN: 1465-5411

inserm-01412032
http://www.hal.inserm.fr/inserm-01412032
http://www.hal.inserm.fr/inserm-01412032/document
http://www.hal.inserm.fr/inserm-01412032/file/13058_2016_Article_780.pdf
DOI : 10.1186/s13058-016-0780-7

Éditeur(s) : HAL CCSD BioScientifica
Résumé : International audience
Spermatogenesis is a complex and tightly regulated process leading to the continuous production of male gametes, the spermatozoa. This developmental process requires the sequential and coordinated expression of thousands of genes, including many that are testis-specific. The molecular networks underlying normal and pathological spermatogenesis have been widely investigated in recent decades, and many high-throughput expression studies have studied genes and proteins involved in male fertility. In this review, we focus on studies that have attempted to correlate transcription and translation during spermatogenesis by comparing the testicular transcriptome and proteome. We also discuss the recent development and use of new transcriptomic approaches that provide a better proxy for the proteome, from both qualitative and quantitative perspectives. Finally, we provide illustrations of how testis-derived transcriptomic and proteomic data can be integrated to address new questions and how the 'proteomics informed by transcriptomics' technique, by combining RNA-seq and MS-based proteomics, can contribute significantly to the discovery of new protein-coding genes or new protein isoforms expressed during spermatogenesis.
ISSN: 1470-1626

hal-01214005
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01214005
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01214005/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01214005/file/Linking%20transcriptomics%20and%20proteomics%20in%20spermatogenesis.pdf
DOI : 10.1530/REP-15-0073

Éditeur(s) : EDP Sciences
Résumé : The cost of ecosystem services degradation is a major topic as underlined by the TEEB program (The Economics of Ecosystems and Biodiversity), which proposed an assessment of the costs of policy inaction in the field of biodiversity conservation. In the same vein, the report of the French Centre for Strategic Analysis on the Economic Approach to Biodiversity and Ecosystem Services turns its attention to the value of ecosystem services, suggesting some elements that could help measure the cost of biodiversity degradation. There is however some confusion regarding the notion of cost. Thus, in the case of TEEB the proposed cost assessment translates into monetary terms the loss of potential profits from ecological services. Yet, another way of assessing these costs could be to estimate the investment required to maintain the ecological potential of ecosystems to deliver these services. This latter approach may be considered better suited to the concept of “inaction” proposed by the TEEB report. In addressing this point, the paper attempts to identify the operational implications of these two assessment methods and their links with decision-making. One of our findings is that the economic approach to biodiversity tends to focus systematically on the question of the monetary value of ecosystem services while regulatory texts increasingly consider the cost assessment of maintaining ecosystem services.
La question des coûts de l’érosion des services écologiques est un sujet très important, comme l’a souligné le programme TEEB (The Economics of Ecosystems and Biodiversity), qui a proposé une évaluation des coûts de l’inaction politique dans le domaine de la conservation de la biodiversité. Dans la même veine, le rapport du Centre d’analyse stratégique, intitulé Approche économique de la biodiversité et des services liés aux écosystèmes, s’est intéressé à la question de la valeur des services écosystémiques et a proposé quelques éléments qui permettraient d’évaluer le coût de leur érosion. Il existe cependant une certaine confusion autour de cette notion de coût. Ainsi, dans le cas du TEEB, l’évaluation proposée des coûts traduit en termes monétaires la perte de bénéfices potentiels que les services écologiques perdus auraient pu délivrer à l’horizon 2050. Mais une autre manière d’évaluer ces coûts aurait pu être d’estimer les investissements à réaliser pour maintenir les capacités écologiques des écosystèmes à délivrer ces services. En approfondissant ce point, le présent article permet de souligner les différences entre les implications opérationnelles de ces deux approches, mais aussi leurs connexions avec des processus décisionnels précis. Une de nos conclusions est que l’approche économique de la biodiversité a tendance à se focaliser systématiquement sur la question de la valeur monétaire des services écologiques, alors que l’évaluation des coûts de maintien des potentialités écologiques dont dispose la biodiversité pour délivrer des services écosystémiques semble être aujourd’hui privilégiée dans les textes réglementaires.
Natures Sciences et Sociétés (1240-1307) (EDP Sciences), 2012 , Vol. 20 , P. 16-29

Droits : NSS-Dialogues, EDP Sciences 2012
http://archimer.ifremer.fr/doc/00120/23115/20960.pdf
DOI:10.1051/nss/2012003
http://archimer.ifremer.fr/doc/00120/23115/

Résumé : Selon les théories classiques du pouvoir, les relations asymétriques favorisent généralement l’acteur le plus puissant en termes de ressources. Toutefois, la partie la plus puissante au niveau de la force et des ressources ne gagne pas toujours dans les négociations. Cela dépend de plusieurs facteurs et notamment des tactiques de négociation de la partie la plus faible. Notre thèse vise justement à analyser un certain nombre de stratégies de négociations que peuvent mener les parties les plus faibles pour obtenir des gains. Afin d’illustrer nos propos, nous avons choisi l’exemple donné par un certain nombre de pays en voie de développement (PVD) pour contester le brevet sur le vivant contenu dans l’Accord sur les aspects des droits de la propriété intellectuelle (ADPIC). Notre objectif a été de comprendre les principales stratégies qu’ils ont employées pour remettre en question cette norme et la rééquilibrer. Afin de réaliser ce travail, nous nous sommes servis du concept d’hégémonie de Gramsci et de cadre emprunté à la littérature des mouvements sociaux. Cela nous a permis de poser l’hypothèse selon laquelle l’Accord sur les ADPIC constitue une norme hégémonique qui avantage essentiellement quelques pays développés et des entreprises internationales. Cependant, cette domination se cache derrière un discours universel et positif visant à susciter une forte adhésion. Ainsi, dans un tel cas de figure, les PVD ne peuvent pas espérer la remettre en question sans un changement de perception. Il faut donc que les règles perçues comme justes et immuables soient cadrées comme injustes et mutables, pour que les pays décident de les contester. Nous avons alors testé cette hypothèse à travers une analyse de contenu du discours officiel des PVD à l’Organisation mondiale du commerce. Ce travail nous a permis d’observer que le cadrage est un instrument important pour lutter contre l’hégémonie d’une norme. En effet, il offre la faculté de montrer que le brevet sur le vivant, loin de présenter que des avantages, est aussi une source de problèmes auxquels il faut apporter des solutions. Le cadre constitue aussi un bon moyen pour élaborer des propositions normatives alternatives. Toutefois, nous avons constaté que cette stratégie est insuffisante pour traduire les propositions des PVD en normes contraignantes. Afin d’obtenir certains changements normatifs, l’élaboration de coalitions s’avère particulièrement pertinente pour les PVD. De même, nous avons noté que les PVD qui demandent des changements normatifs quand la structure des opportunités politiques est ouverte ont plus de chance d’obtenir satisfaction de leurs revendications. La présente thèse nous offre ainsi un portrait général de stratégies de négociation et démontre que sous certaines conditions les parties les plus faibles peuvent obtenir certains gains dans une négociation asymétrique.
According to the classical theories of power, asymmetrical relations generally favor the most powerful actor in terms of resources. However, the most powerful in terms of strength and resources part does not always win in negotiations. This depends on several factors, including negotiation tactics of the weaker party. Our thesis aims to analyze different type of negotiation strategies that weaker parties can use to obtain some benefit. To illustrate this point, we chose the example set by a number of developing countries (DV) to challenge the patenting of life contained in the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS). Our goal was to understand the key strategies they have used to question this norm and rebalance it. To make this work, we used the concept of hegemony conceptualized by Gramsci and the concept of framework borrowed from the literature of social movements. This tool has allowed us to make the assumption that TRIPS is a hegemonic norm that mainly benefit to few developed countries and international companies. However, this domination is hidden by the norms thanks to universal and positive discourse which help to generate strong adhesion. Thus, in such a case, developing countries can’t expect to challenge this norm without a change of perception. It is therefore necessary that the rules perceived as fair and immutable are framed as unjust and mutable, so that countries decide to challenge it. We then tested this hypothesis through a content analysis of the DC’s official discourse at the World Trade Organization. This work has allowed us to observe that the framing is an important tool in the fight against the norm’s hegemony. Indeed, it offers the possibility to show that the patenting of life, far from presenting just a source of benefits, is also a source of problems that need solutions. The frame is also a good way to develop alternative normative propositions. However, we found that this strategy is insufficient to translate DC’s proposals into binding norms. In order to obtain changes in the agreement, building coalitions is particularly relevant for DC. Furthermore, we noted that DC which require regulatory changes when the structure of political opportunities is opened are more likely to obtain what they want. This thesis offers us a general picture of negotiations strategies and reveal that under certain conditions the weaker parties can get some gains in an asymmetrical negotiation.

http://www.theses.fr/2013AGUY0642/document