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See detailThe functional anatomy of inhibition processes investigated with the Hayling task
Collette, Fabienne ULg; Van der Linden, Martial ULg; Delfiore, Guy et al

in Neuroimage (2001), 14(2), 258-267

The cortical areas involved in inhibition processes were examined with positron emission tomography (PET). The tasks administered to subjects were an adaptation of the Hayling test. In the first condition ... [more ▼]

The cortical areas involved in inhibition processes were examined with positron emission tomography (PET). The tasks administered to subjects were an adaptation of the Hayling test. In the first condition (response initiation), subjects had to complete sentences with a word clearly suggested by the context, whereas in the second condition (response inhibition), subjects had to produce a word that made no sense in the context of the sentence. Results indicated that the response initiation processes were associated to increases of activity in the left inferior frontal gyrus (BA 45/47), whereas response inhibition processes led to increases in a network of left prefrontal areas, including the middle (BA 9 and BA 10) and inferior (BA 45) frontal areas. [less ▲]

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See detailFunctional anatomy of verbal and visuospatial span tasks in Alzheimer's disease
Collette, Fabienne ULg; Salmon, Eric ULg; Van der Linden, Martial ULg et al

in Human Brain Mapping (1997), 5(2), 110-118

The aim of the study was to emphasize cerebral regions which subserve the performance of short-term memory tasks in patients with Alzheimer's disease. We correlated scores obtained on span tasks with ... [more ▼]

The aim of the study was to emphasize cerebral regions which subserve the performance of short-term memory tasks in patients with Alzheimer's disease. We correlated scores obtained on span tasks with cerebral metabolism measured at rest with positron emission tomography. Scores obtained on the digit span task correlated with glucose metabolism in a brain area centered on the premotor cortex and extending to the adjacent motor and parietal gyri. There exists some evidence suggesting that this area may subserve the sequential organization of material stored in short-term memory. In a secondary analysis, we also observed significant interregional correlations between left-sided brain areas which are part of the neural network subserving verbal working memory processes in healthy controls. These data suggest that individual performance on verbal span tasks in AD patients may essentially depend on the preservation of their ordination processing capacity. The absence of correlation with prefrontal regions suggests that AD patients might not spontaneously engage central executive resources to reach their maximal span score. For simultaneous visuospatial span task, the performance of patients correlated with posterior brain regions, and not with prefrontal cortices. Hum. Brain Mapping 5:110-118, 1997. © 1997 Wiley-Liss Inc. [less ▲]

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See detailFunctional and cooperative interactions between the homeodomain PDX1, Pbx, and Prep1 factors on the somatostatin promoter
Goudet, Ghylène; Delhalle, Sylvie; Biemar, Frédéric et al

in Journal of Biological Chemistry (1999), 274(7), 4067-73

Expression of the somatostatin gene in endocrine pancreatic cells is controlled by several regulatory cis-elements located in the promoter region. Among these, the adjacent UE-A and TSEI elements, located ... [more ▼]

Expression of the somatostatin gene in endocrine pancreatic cells is controlled by several regulatory cis-elements located in the promoter region. Among these, the adjacent UE-A and TSEI elements, located from -113 to -85 relative to the transcription initiation site, function in combination and act as a pancreas-specific mini-enhancer. The TSEI element is recognized by the pancreatic homeodomain factor PDX1. In the present study, we show that the UE-A element binds a heterodimeric complex composed of a Pbx factor and the Prep1 protein, both belonging to the atypical three-amino acid loop extension homeodomain family. Recombinant Pbx1 and Prep1 proteins bind cooperatively to the UE-A site, whereas neither protein can bind this site alone. Transient transfection experiments reveal that both Pbx1 and Prep1 are required to generate a strong transcriptional activation from the UE-A element when this element is inserted close to the TATA box. In contrast, in the context of the intact somatostatin promoter or mini-enhancer, Pbx1 and Prep1 alone have no effect, but they produce a drastic activation when the pancreatic homeodomain factor PDX1 is also coexpressed. Thus, the activity of the somatostatin mini-enhancer is mediated by a cooperative interaction between the Pbx-Prep1 heterodimeric complex and the pancreatic factor PDX1. [less ▲]

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See detailFunctional and Evolutionary Analysis of Flatfish Gonadotropin Receptors Reveals Cladal- and Lineage-Level Divergence of the Teleost Glycoprotein Receptor Family
Chauvigné, Francois; Tingaud-Sequeira, Angele; Agulleiro, Maria J et al

in Biology of Reproduction (2010), 82

Pituitary gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) act via their cognate glycoprotein hormone receptors (GpHRs), FSH receptor (FSHR), and LH/ choriogonadotropin ... [more ▼]

Pituitary gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) act via their cognate glycoprotein hormone receptors (GpHRs), FSH receptor (FSHR), and LH/ choriogonadotropin receptor (LHCGR) to regulate gonad physiology. Here, we show that the flatfish Senegalese sole (Solea senegalensis) expresses functional isoforms of fshr and lhcgr, but the genomic origin, ligand activation, and tissue distribution of the receptor transcripts are more complex than expected. By integrating the molecular phylogeny of GpHRs with the syntenic loci of vertebrate orthologs, and by subsequently characterizing the physical maps with the phylogeny of flanking genes, we found that vertebrate GpHRs have undergone a divergent evolution. In Teleostei, fshr genes have a common descent and can be classified as fshra, whereas lhcgrb genes exist as alternatively coded genes even in closely related species. Structural analyses of the receptors revealed that Fshra has an elongated ligand-binding domain, containing an extra leucinerich repeat that specifically arose in the Acanthomorpha because of exon duplication. Ectopic expression in Xenopus laevis oocytes demonstrated that sole Fshra responded to piscine Fsh and Lh, whereas Lhcgrba was preferentially activated by its cognate hormone. The expression pattern of sole fshra and lhcgrba in gonads during the reproductive cycle was consistent with earlier observations wherein Fshra regulates ovarian growth and spermatogenesis and Lhcgrb triggers gamete maturation, respectively. However, contrary to observations in other teleosts, fshra was localized exclusively in Sertoli cells of the testis, whereas lhcgrba was expressed in Leydig cells as well as in spermatids. These results demonstrate the presence of alternatively coded lhcgr isoforms (lhcgrba and lhcgrbb) in teleosts and suggest a role of the lhcgrba receptor in the differentiation of spermatids into spermatozoa in Senegalese sole. [less ▲]

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See detailFunctional and profiling studies prove that prostate cancer upregulated neuroblastoma thymosin beta is the true human homologue of rat thymosin beta 15
Dhaese, S.; Jonckheere, V.; Goethals, M. et al

in FEBS Letters (2007), 581(25), 4809-4815

A peptide with a sequence identical to rat thymosin beta(Tb)15 was reported to be upregulated in human prostate cancer. However, in this report we provide evidence that TbNB, initially identified in human ... [more ▼]

A peptide with a sequence identical to rat thymosin beta(Tb)15 was reported to be upregulated in human prostate cancer. However, in this report we provide evidence that TbNB, initially identified in human neuroblastoma, is the only Tb isoform upregulated in human prostate cancer and that the Tb15 sequence is not present herein. In addition, we demonstrate that human TbNB has a higher affinity for actin in comparison to Tb4 and promotes cell migration. In combination, this experimentally validates TbNB as functional homologue of rat Tb15 in the human organism and clarifies the current composition of the human Tb family. (c) 2007 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved. [less ▲]

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See detailFunctional and Psychological Characteristics of Belgian Men with Premature Ejaculation and Their Partners
Kempeneers, Philippe ULg; ANDRIANNE, Robert ULg; Bauwens, Sabrina et al

in Archives of Sexual Behavior (2013), 42

Physiological, behavioral, cognitive, and emotional factors are generally acknowledged to play a role in premature ejaculation (PE). However, the nature and the extent of their etiological impact remain ... [more ▼]

Physiological, behavioral, cognitive, and emotional factors are generally acknowledged to play a role in premature ejaculation (PE). However, the nature and the extent of their etiological impact remain largely imprecise. The present study examined functional and psychometric dynamics at work in a PE population. A total of 461 men with PE and 80 partners completed an online questionnaire. The main outcome measures were self-reported ejaculatory latency time, the feeling of control upon ejaculation, sexual satisfaction, distress related to PE, trait anxiety (STAI-B), sexual cognitions (SIQ), social anxiety (LSAS and SISST), and personality traits (TCI-R). In our sample, the median latency time to ejaculation was between 1 and 2 minutes. Sexual satisfaction and distress correlated more strongly with the feeling of control than with the self-reported latency time. Men experienced more distress and dissatisfaction related to PE than did their partners while overestimating their partners’ distress and dissatisfaction. PE participants’ scores differed significantly, albeit slightly, from STAI-B, SIQ, LSAS, and SISST norms. The differences were negligible on TCI-R. Some differences became stronger when subtypes were considered. Participants combining generalized and lifelong PE with self-reported latency times of < 30 sec reported lower sexual satisfaction and control, higher distress, higher social anxiety, and harm avoidance (TCI-R/HA) scores. By contrast, the situational subtype of PE was found to be characterized by a higher level of satisfaction, a greater feeling of control, less distress, and higher trait anxiety scores. However, the trends remained statistically discrete. [less ▲]

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See detailFunctional ANOVA with random functional effects: an application to event-related potentials modelling for electroencephalograms analysis
Bugli, Céline; Lambert, Philippe ULg

in Statistics in Medicine (2006), 25

The di erential e ects of basic visual or auditory stimuli on electroencephalograms (EEG), named event related potentials (ERPs), are often used to evaluate the impact of treatments on brain performances ... [more ▼]

The di erential e ects of basic visual or auditory stimuli on electroencephalograms (EEG), named event related potentials (ERPs), are often used to evaluate the impact of treatments on brain performances. In the present paper, we propose a P-splines based model that can be used to evaluate treatment e ect on the timing and the amplitude of some peaks of the ERPs curves. Functional ANOVA is an adaptation of linear model or analysis of variance to analyse functional observations. The changes in the functional of interest e ects are generally described using smoothing splines. Eilers and Marx proposed to work with P-splines, a combination of B-splines and di erence penalties on coe cients. We de ne a Psplines model for ERPs curves combined with random e ects. In particular, we show that it is a useful alternative to classical strategies requiring the visual and usually imprecise localization of speci c ERP peaks from curves with a low signal-to-noise ratio. [less ▲]

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See detailFunctional brain imaging applications to differential diagnosis in the dementias
Salmon, Eric ULg

in Current Opinion in Neurology (2002), 15(4), 439-444

Purpose of review The diagnosis of dementia rests on an improved knowledge and a better detection of early impairments, to which functional imaging can certainly contribute. Recent findings Progress has ... [more ▼]

Purpose of review The diagnosis of dementia rests on an improved knowledge and a better detection of early impairments, to which functional imaging can certainly contribute. Recent findings Progress has been observed at different levels. First, the understanding of different dementias has benefited from explorations of the neural substrate of dementia symptoms and from research into new markers. Second, diverse variables (clinical, anatomical, biochemical) have been related to impaired cerebral activity in Alzheimer's disease and other dementias, and progress in image analysis and in multimodal data acquisition has allowed a better understanding of the significance of brain activity disturbances. Third, functional imaging has been applied in well-designed clinical studies, and has provided important arguments for the diagnosis of characteristic clinical syndromes in the dementias. Summary The functioning of neural networks responsible for clinical symptoms in dementia remains an important research topic for functional imaging. The development of new tracers and new techniques for image processing should also improve the usefulness of brain imaging as a diagnostic tool. [less ▲]

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See detailFunctional brain imaging of human sleep
Maquet, Pierre ULg; Phillips, Christophe ULg

in Journal of Sleep Research (1998), 7(Suppl. 1), 42-47

This paper presents an overview of the contribution of functional brain mapping to the study of human sleep. Early studies were essentially successful in describing the variations of the global level of ... [more ▼]

This paper presents an overview of the contribution of functional brain mapping to the study of human sleep. Early studies were essentially successful in describing the variations of the global level of cerebral metabolism. More recently, regional distribution of cerebral blood flow was reported. The results suggest that the permissive and executive processes of slow wave sleep and REM sleep are similar in humans and in animals. They also show cortical blood flow distributions specific to each sleep stage. The cellular mechanisms underlying the involvement of these cortical areas in sleep are not yet precisely known. They should be looked for by further investigations in animals. Future research in functional neuroimaging will attempt to explore functional and, hopefully, effective connectivity between cerebral areas involved in sleep processes. This final goal will probably require the co-registration of two or more brain imaging techniques to precisely describe the spatio-temporal course of neuronal interactions occurring during sleep. [less ▲]

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See detailFunctional Changes Induced by Necrotic Laryngitis in Double Muscled Calves
Lekeux, Pierre ULg; Art, Tatiana ULg

in Veterinary Record : Journal of the British Veterinary Association (1987), 121(15), 353-355

The effects of necrotic laryngitis on the mechanics of breathing and gas exchange were investigated in five Belgian blue double muscled calves two to three months old. All the animals showed the typical ... [more ▼]

The effects of necrotic laryngitis on the mechanics of breathing and gas exchange were investigated in five Belgian blue double muscled calves two to three months old. All the animals showed the typical clinical picture of the respiratory syndrome associated with naturally occurring necrotic laryngitis. Highly significant increases in total pulmonary resistance, minute viscous work of breathing and alveolar-arterial oxygen gradient, and highly significant decreases in dynamic lung compliance and arterial oxygen tension were recorded in the infected animals, when compared to reference values for healthy cattle. The ratio of inspiratory to expiratory viscous work of breathing was also significantly increased probably because of a partial collapse of the extrathoracic trachea during inspiration. It was concluded that necrotic laryngitis disturbs pulmonary function to such an extent that it impedes the growing process and predisposes the infected animals to secondary bronchopneumonia and ventilatory failure due to respiratory muscle fatigue. [less ▲]

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See detailFunctional characteristics of TauA binding protein from TauABC Escherichia coli system
Javaux, C.; Joris, Bernard ULg; De Witte, P.

in Protein Journal (2007), 26(4), 231-238

Although TauA shares few common characteristics with other known periplasmic binding protein, TauA is a putative periplasmic binding protein, part of tauABCD gene cluster involved in sulfonate transport ... [more ▼]

Although TauA shares few common characteristics with other known periplasmic binding protein, TauA is a putative periplasmic binding protein, part of tauABCD gene cluster involved in sulfonate transport in sulphate starvation condition. This protein was expressed in E. coli BL 21 and purified before to assess its binding functionalities. Measurement of K (d) value (mean 11.3 nM) by binding/dialysis studies revealed high affinity and specificity with taurine and also indicated that TauA possessed a unique binding site for its ligand. Comparisons with other periplasmic binding proteins suggests TauA plays a major role in ABC transport system and could be ideal candidate to serve as taurine catcher in biological fluids. [less ▲]

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See detailFunctional characterization of new allelic polymorphisms identified in the promoter region of the human MxA gene.
Tran Thi Duc, Tam; Desmecht, Daniel ULg; Cornet, Anne

in International Journal of Immunogenetics (2013), 40

The Mx proteins are high-molecular-weight dynamin-like proteins whose expression depends strictly on type-I and -III interferons (IFN). Some isoforms are able to inhibit the life cycle of one or several ... [more ▼]

The Mx proteins are high-molecular-weight dynamin-like proteins whose expression depends strictly on type-I and -III interferons (IFN). Some isoforms are able to inhibit the life cycle of one or several viruses and are thus components of innate immune response. The human MxA protein displays the broadest antiviral spectrum which makes it appear as a key antiviral effector of innate immunity. Allelic polymorphisms located in the MxA gene promoter can be expected to affect the magnitude of MxA mRNA transcription in response to IFNs and therefore to alter the severity of viral diseases in humans. Here, three single nucleotide polymorphism sites (-309, -101 and +20) were examined for their ability to alter MxA gene promoter-driven reporter expression. We show that, besides the previously reported role of 123A and -88T, the presence of -101G is equally important. Moreover, when a promoter construct carries these three critical nucleotides, a first additional positive effect is conferred by a C at position -309 and, in this latter case, a second additional effect is produced by a A at position +20. This finding is clinically useful to improve prediction of IFN-responsiveness in patients not only with viral diseases for which type-I IFN therapy is used. [less ▲]

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See detailFunctional connectivity and dynamic causal modeling
Phillips, Christophe ULg

Scientific conference (2010, May 03)

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See detailFunctional connectivity and recognition of familiar faces in Alzheimer’s disease
Kurth, Sophie ULg; Bahri, Mohamed Ali ULg; Moyse, Evelyne ULg et al

in Frontiers in Human Neuroscience (2014)

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See detailFunctional connectivity in the default network during resting state is preserved in a vegetative but not in a brain dead patient.
Boly, Mélanie ULg; Tshibanda, Luaba ULg; Vanhaudenhuyse, Audrey ULg et al

in Human Brain Mapping (2009), 30(8), 2393-400

Recent studies on spontaneous fluctuations in the functional MRI blood oxygen level-dependent (BOLD) signal in awake healthy subjects showed the presence of coherent fluctuations among functionally ... [more ▼]

Recent studies on spontaneous fluctuations in the functional MRI blood oxygen level-dependent (BOLD) signal in awake healthy subjects showed the presence of coherent fluctuations among functionally defined neuroanatomical networks. However, the functional significance of these spontaneous BOLD fluctuations remains poorly understood. By means of 3 T functional MRI, we demonstrate absent cortico-thalamic BOLD functional connectivity (i.e. between posterior cingulate/precuneal cortex and medial thalamus), but preserved cortico-cortical connectivity within the default network in a case of vegetative state (VS) studied 2.5 years following cardio-respiratory arrest, as documented by extensive behavioral and paraclinical assessments. In the VS patient, as in age-matched controls, anticorrelations could also be observed between posterior cingulate/precuneus and a previously identified task-positive cortical network. Both correlations and anticorrelations were significantly reduced in VS as compared to controls. A similar approach in a brain dead patient did not show any such long-distance functional connectivity. We conclude that some slow coherent BOLD fluctuations previously identified in healthy awake human brain can be found in alive but unaware patients, and are thus unlikely to be uniquely due to ongoing modifications of conscious thoughts. Future studies are needed to give a full characterization of default network connectivity in the VS patients population. [less ▲]

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See detailFunctional Development of Advanced Driver Assistance Systems by means of Driving Simulators
Christen, Fréderic ULg; Benmimoun, A.; Deutschle, S.

Poster (2008, April 16)

Der Beitrag beschreibt die Funktionsentwicklung von Fahrerassistenzsystemen an der Forschungsgesellschaft Kraftfahrwesen mbH Aachen (fka) und am Institut für Kraftfahrwesen (ika) der RWTH Aachen mittels ... [more ▼]

Der Beitrag beschreibt die Funktionsentwicklung von Fahrerassistenzsystemen an der Forschungsgesellschaft Kraftfahrwesen mbH Aachen (fka) und am Institut für Kraftfahrwesen (ika) der RWTH Aachen mittels Fahrsimulatoren. Dabei wird konkret auf die Entwicklung eines Kreuzungsassistenten sowie eines sogenannten KONVOI-Systems eingegangen. Beide Systeme wurden u.a. unter Verwendung des statischen Fahrsimulators InDriveS entwickelt. Der in diesem Beitrag vorgestellte Ansatz eines Kreuzungsassistenten basiert auf Kommunikation: Fahrzeug-Fahrzeug-Kommunikation (C2C) und Infrastruktur-Fahrzeug- Kommunikation (I2C). Hierfür wurden in der Verkehrsfluss- und Fahrsimulation verschiedene Systemvarianten betrachtet, um unterschiedliche Stufen der Systemkomplexität und unter- schiedliche Zeitrahmen für die Realisierung eines solchen Assistenten zu berücksichtigen. Jede dieser Systemvarianten wurde hinsichtlich deren Wirkung auf die Verkehrssicherheit bewertet. Daneben wurde auch die Benutzerakzeptanz unter Berücksichtigung verschiedener Mensch-Maschine-Schnittstellen betrachtet. Die Ergebnisse zeigen, dass die Kommunikationsreichweite der wichtigste Parameter für die Systemauslegung und -spezifikation darstellt. Für die Wirkung des Kreuzungsassistenten auf die Verkehrssicherheit ist in erster Linie der Ausrüstungsgrad entscheidend. Für die Benutzerakzeptanz ist die Detektionsrate von möglichen Konfliktsituationen und die Vermeidung von kritischen Situationen entscheidend. Das dargestellte KONVOI-System ermöglicht die Automatisierung von Nutzfahrzeugkolonnen auf Autobahnen. Neben der Funktionsentwicklung zur automatischen Abstandsregelung und Querführung werden in dem Projekt die Auswirkungen von KONVOIs auf den übrigen Verkehr analysiert und die bei den Fahrern auftretenden Belastungen und die Akzeptanz des Systems untersucht. Begleitend werden rechtliche Aspekte der kommerziellen Nutzung von Lkw-KONVOIs in Deutschland weiterentwickelt. Um die Komplexität der zu entwickelnden Lösungen zur Funktionserweiterung der Fahrzeuge zu bewältigen und eine hohe Zuverlässigkeit der Systeme zu gewährleisten, erfolgt die Systementwicklung mit Hilfe von Simulationswerkzeugen (MATLAB/Simulink, Stateflow, Verkehrsflusssimulation PELOPS und Lkw- Fahrsimulator InDriveS). Abschließend geht der Beitrag auf den neuen dynamischen Fahrsimulator der RWTH Aachen ein. [less ▲]

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See detailA Functional Diachronic Approach to Prolepsis: The Complementation of PCU Verbs in Ancient Egyptian
Grossman, Eitan; Polis, Stéphane ULg

Conference (2010, June 01)

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See detailFunctional distribution and dynamics of Arabidopsis SR splicing factors in living plant cells
Tillemans, Vinciane ULg; Dispa, Laurence ULg; Remacle, Claire ULg et al

in Plant Journal (The) (2005), 41(4), 567-582

Serine/arginine-rich (SR) proteins constitute an important class of splicing regulators in higher eukaryotes that share a modular structure consisting of one or two N-terminal RNA recognition motif (RRM ... [more ▼]

Serine/arginine-rich (SR) proteins constitute an important class of splicing regulators in higher eukaryotes that share a modular structure consisting of one or two N-terminal RNA recognition motif (RRM) domains and a C-terminal RS-rich domain. Herein, we have investigated the in vivo functional distribution of Arabidopsis SR factors. Agrobacterium-mediated transient transformation revealed nuclear speckled distribution and the overall colocalization of fluorescent protein (FP)-tagged SR factors in both tobacco and Arabidopsis cells. Their overall colocalization in larger nucleoplasmic domains was further observed after transcriptional and phosphorylation/dephosphorylation inhibition, indicating a close functional association between SR factors, independent of their phosphorylation state. Furthermore, we demonstrated in vivo the conserved role of the RS and RRM domains in the efficient targeting of Arabidopsis SR proteins to nuclear speckles by using a series of structural domain-deleted mutants of atRSp31 and atRSZp22. We suggest additional roles of RS domain such as the shuttling of atRSZp22 between nucleoplasm and nucleolus through its phosphorylation level. The coexpression of deletion mutants with wild-type SR proteins revealed potential complex associations between them. Fluorescence recovery after photobleaching demonstrated similar dynamic properties of SR factors in both tobacco transiently expressing cells and Arabidopsis transgenics. Cell cycle phase-dependent organization of FP-tagged SR proteins was observed in living tobacco BY-2 cells. We showed that atRSp31 is degraded at metaphase by fluorescence quantification. SR proteins also localized within small foci at anaphase. These results demonstrate interesting related features as well as potentially important differences between plant and animal SR proteins. [less ▲]

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See detailFunctional diversity of microbial communities associated to the mucus of scleractinians around Moorea (French Polynesia)
Ladrière, Ophélie ULg; Theunis, Laetitia; Wilmotte, Annick et al

Poster (2008, July 07)

Mucus production by scleractinians appears as an antifouling mechanism which prevents settlement of other organisms and accumulation of sediments on their surface. This Surface Muccopolysaccharide Layer ... [more ▼]

Mucus production by scleractinians appears as an antifouling mechanism which prevents settlement of other organisms and accumulation of sediments on their surface. This Surface Muccopolysaccharide Layer (SML) harbours dense populations of bacteria which play a paramount role in scleractinians nutrition, metabolism and good health maintenance. However, environmental disturbances can alter these microbiocenoses. Characterization of bacterial communities was carried out using a set of simple techniques that enable us to describe the state and functions of whole microbial communities associated with different hard coral species. Multi-comparisons have been performed on bacterial communities from open water, interstitial water, sedimentary interface and macro algae as well as between healthy and bleached colonies, and patches associated or not with Pomacentridae fishes. The functional study included measurements of bacterial biomass, respiration, oxydative and hydrolytic metabolisms. Non-Fungiidae corals and sedimentary interface have a quite similar bacterial biomass but open water, interstitial water and macro-algae are characterized by higher bacterial biomass. Bacterial respiration potential is similar on corals and at the sedimentary interface, but it is higher in interstitial water and lower in open water and for bacterial community associated with macro-algae. Hydrolytic activities are highest in SML. Bleached corals and patches associated with Pomacentridae fishes show more abundant bacteria, with higher respiration rate and higher hydrolytic activity than corals without fishes and healthy ones. In addition, bacteria of bleached corals display a higher division percentage, a higher growth rate and a lower turn-over time We confirmed that bleaching events or the presence of sedentary fishes modify the bacterial communities structure and affect relationships between coral, endosymbiotic algae, SML-associated microbial community and associated organisms. Such results highlight that SML-bacterial communities are modified by bleaching and raise the question of a potential protection of fishes against pathogens. [less ▲]

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