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991.
Johanne Saint-Charles Jena Webb Andres Sanchez Hein Mallee Berna van Wendel de Joode Hung Nguyen-Viet 《EcoHealth》2014,11(3):300-307
This forum paper proposes a reflection on the “field of ecohealth” and on how best to sustain a supportive environment that enables the evolution of diverse partnerships and forms of collaboration in the field. It is based on the results of a preconference workshop held in October 2012, in Kunming, China at the fourth biennial conference of the International Association for Ecology and Health. Attended by 105 persons from 38 countries, this workshop aimed to have a large-group and encompassing discussion about ecohealth as an emerging field, touching on subjects such as actors, processes, structures, standards, and resources. Notes taken were used to conduct a qualitative thematic analysis combined with a semantic network analysis. Commonalities highlighted by these discussions draw a portrait of a field in which human health, complex systems thinking, action, and ecosystem health are considered central issues. The need to reach outside of academia to government and the general public was identified as a shared goal. A disconnect between participants’ main concerns and what they perceived as the main concerns of funding agencies emerged as a primary roadblock for the future. 相似文献
992.
Virginie Licker Natacha Turck Enikö Kövari Karim Burkhardt Mélanie Côte Maria Surini‐Demiri Johannes A. Lobrinus Jean‐Charles Sanchez Pierre R. Burkhard 《Proteomics》2014,14(6):784-794
Parkinson's disease (PD) pathology spreads throughout the brain following a region‐specific process predominantly affecting the substantia nigra (SN) pars compacta. SN exhibits a progressive loss of dopaminergic neurons responsible for the major cardinal motor symptoms, along with the occurrence of Lewy bodies in the surviving neurons. To gain new insights into the underlying pathogenic mechanisms in PD, we studied postmortem nigral tissues dissected from pathologically confirmed PD cases (n = 5) and neurologically intact controls (n = 8). Using a high‐throughput shotgun proteomic strategy, we simultaneously identified 1795 proteins with concomitant quantitative data. To date, this represents the most extensive catalog of nigral proteins. Of them, 204 proteins displayed significant expression level changes in PD patients versus controls. These were involved in novel or known pathogenic processes including mitochondrial dysfunction, oxidative stress, or cytoskeleton impairment. We further characterized four candidates that might be relevant to PD pathogenesis. We confirmed the differential expression of ferritin‐L and seipin by Western blot and demonstrated the neuronal localization of gamma glutamyl hydrolase and nebulette by immunohistochemistry. Our preliminary findings suggest a role for nebulette overexpression in PD neurodegeneration, through mechanisms that may involve cytoskeleton dynamics disruption. All MS data have been deposited in the ProteomeXchange with identifier PXD000427 ( http://proteomecentral.proteomexchange.org/dataset/PXD000427 ). 相似文献
993.
Maria S. Jaureguiberry M. Alejandra Tricerri Susana A. Sanchez Gabriela S. Finarelli Mauro A. Montanaro Eduardo D. Prieto Omar J. Rimoldi 《Acta biochimica et biophysica Sinica》2014,(4):273-282
Experimental evidence has suggested that plasma membrane (PM)-associated signaling and hence cell metabolism and viability depend on lipid composition and organization. The aim of the present work is to develop a cell model to study the endogenous polyunsaturated fatty acids (PUFAs) effect on PM properties and analyze its influence on cholesterol (Chol) homeostasis. We have previously shown that by using a cell line overexpressing stearoyl-CoA-desaturase, membrane composition and organization coordinate cellular pathways involved in Chol efflux and ceil viability by different mechanisms. Now, we expanded our studies to a cell model overexpressing both A5 and A6 desaturases, which resulted in a permanently higher PUFA content in PM. Furthermore, this cell line showed increased PM fluidity, Chol storage, and mitochondrial activity. In addition, human apolipoprotein AI-mediated Chol removal was less efficient in these cells than in the corresponding control. Taken together, our results suggested that the ceil functionality is preserved by regulating PM organization and Chol exportation and homeostasis. 相似文献
994.
Ana Peiro Ana Cristina Izquierdo‐Garcia Jesus Angel Sanchez‐Navarro Vicente Pallas Jose Miguel Mulet Frederic Aparicio 《Molecular Plant Pathology》2014,15(9):881-891
Movement proteins (MPs) encoded by plant viruses interact with host proteins to facilitate or interfere with intra‐ and/or intercellular viral movement. Using yeast two‐hybrid and bimolecular fluorescence complementation assays, we herein present in vivo evidence for the interaction between Alfalfa mosaic virus (AMV) MP and Arabidopsis Patellin 3 (atPATL3) and Patellin 6 (atPATL6), two proteins containing a Sec14 domain. Proteins with Sec14 domains are implicated in membrane trafficking, cytoskeleton dynamics, lipid metabolism and lipid‐mediated regulatory functions. Interestingly, the overexpression of atPATL3 and/or atPATL6 interfered with the plasmodesmata targeting of AMV MP and correlated with reduced infection foci size. Consistently, the viral RNA levels increased in the single and double Arabidopsis knockout mutants for atPATL3 and atPATL6. Our results indicate that, in general, MP–PATL interactions interfere with the correct subcellular targeting of MP, thus rendering the intracellular transport of viral MP‐containing complexes less efficient and diminishing cell‐to‐cell movement. 相似文献
995.
Catalina Arenas-Huertero Beatriz Pérez Fernando Rabanal Daniel Blanco-Melo Carlos De la Rosa Georgina Estrada-Navarrete Federico Sanchez Alejandra Alicia Covarrubias José Luis Reyes 《Plant molecular biology》2009,70(4):385-401
MicroRNAs (miRNAs) are small RNA molecules recognized as important regulators of gene expression. Although plant miRNAs have
been extensively studied in model systems, less is known in other plants with limited genome sequence data. We are interested
in the identification of miRNAs in Phaseolus vulgaris (common bean) to uncover different plant strategies to cope with adverse conditions and because of its relevance as a crop
in developing countries. Here we present the identification of conserved and candidate novel miRNAs in P. vulgaris present in different organs and growth conditions, including drought, abscisic acid treatment, and Rhizobium infection. We also identified cDNA sequences in public databases that represent the corresponding miRNA precursors. In addition,
we predicted and validated target mRNAs amongst reported EST and cDNAs for P. vulgaris. We propose that the novel miRNAs present in common bean and other legumes, are involved in regulation of legume-specific
processes including adaptation to diverse external cues.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
996.
Goudreault M D'Ambrosio LM Kean MJ Mullin MJ Larsen BG Sanchez A Chaudhry S Chen GI Sicheri F Nesvizhskii AI Aebersold R Raught B Gingras AC 《Molecular & cellular proteomics : MCP》2009,8(1):157-171
The serine/threonine protein phosphatases are targeted to specific subcellular locations and substrates in part via interactions with a wide variety of regulatory proteins. Understanding these interactions is thus critical to understanding phosphatase function. Using an iterative affinity purification/mass spectrometry approach, we generated a high density interaction map surrounding the protein phosphatase 2A catalytic subunit. This approach recapitulated the assembly of the PP2A catalytic subunit into many different trimeric complexes but also revealed several new protein-protein interactions. Here we define a novel large multiprotein assembly, referred to as the striatin-interacting phosphatase and kinase (STRIPAK) complex. STRIPAK contains the PP2A catalytic (PP2Ac) and scaffolding (PP2A A) subunits, the striatins (PP2A regulatory B' subunits), the striatin-associated protein Mob3, the novel proteins STRIP1 and STRIP2 (formerly FAM40A and FAM40B), the cerebral cavernous malformation 3 (CCM3) protein, and members of the germinal center kinase III family of Ste20 kinases. Although the function of the CCM3 protein is unknown, the CCM3 gene is mutated in familial cerebral cavernous malformations, a condition associated with seizures and strokes. Our proteomics survey indicates that a large portion of the CCM3 protein resides within the STRIPAK complex, opening the way for further studies of CCM3 biology. The STRIPAK assembly establishes mutually exclusive interactions with either the CTTNBP2 proteins (which interact with the cytoskeletal protein cortactin) or a second subcomplex consisting of the sarcolemmal membrane-associated protein (SLMAP) and the related coiled-coil proteins suppressor of IKKepsilon (SIKE) and FGFR1OP2. We have thus identified several novel PP2A-containing protein complexes, including a large assembly linking kinases and phosphatases to a gene mutated in human disease. 相似文献
997.
The Schizosaccharomyces pombe exchange factor Rgf1p specifically regulates Rho1p during polarized growth. Rgf1p activates the β-glucan synthase (GS) complex containing the catalytic subunit Bgs4p and is involved in the activation of growth at the second end, a transition that requires actin reorganization. In this work, we investigated Rgf1p signaling and observed that Rgf1p acted upstream from the Pck2p-Pmk1p MAPK signaling pathway. We noted that Rgf1p and calcineurin play antagonistic roles in Cl− homeostasis; rgf1Δ cells showed the vic phenotype (viable in the presence of immunosuppressant and chlorine ion) and were unable to grow in the presence of high salt concentrations, both phenotypes being characteristic of knockouts of the MAPK components. In addition, mutations that perturb signaling through the MAPK pathway resulted in defective cell integrity (hypersensitivity to caspofungin and β-glucanase). Rgf1p acts by positively regulating a subset of stimuli toward the Pmk1p-cell integrity pathway. After osmotic shock and cell wall damage HA-tagged Pmk1p was phosphorylated in wild-type cells but not in rgf1Δ cells. Finally, we provide evidence to show that Rgf1p regulates Pmk1p activation in a process that involves the activation of Rho1p and Pck2p, and we demonstrate that Rgf1p is unique in this signaling process, because Pmk1p activation was largely independent of the other two Rho1p-specific GEFs, Rgf2p and Rgf3p. 相似文献
998.
Drug resistance represents a major obstacle in the radical control of malaria. Drug resistance can arise in many different ways, but recent developments highlight the importance of mutations in transporter molecules as being major contributors to drug resistance in the human malaria parasite Plasmodium falciparum. While approximately 2.5% of the P. falciparum genome encodes membrane transporters, this review concentrates on three transporters, namely the chloroquine resistance transporter PfCRT, the multi-drug resistance transporter 1 PfMDR1, and the multi-drug resistance-associated protein PfMRP, which have been strongly associated with resistance to the major antimalarial drugs. The studies that identified these entities as contributors to resistance, and the possible molecular mechanisms that can bring about this phenotype, are discussed. A deep understanding of the underpinning mechanisms, and of the structural specificities of the players themselves, is a necessary basis for the development of the new drugs that will be needed for the future armamentarium against malaria. 相似文献
999.
Sharon Perry Bouke C. de Jong Jay V. Solnick Maria de la Luz Sanchez Shufang Yang Philana Ling Lin Lori M. Hansen Najeeha Talat Philip C. Hill Rabia Hussain Richard A. Adegbola JoAnne Flynn Don Canfield Julie Parsonnet 《PloS one》2010,5(1)
Background
Helicobacter pylori, a lifelong and typically asymptomatic infection of the stomach, profoundly alters gastric immune responses, and may benefit the host in protection against other pathogens. We explored the hypothesis that H. pylori contributes to the control of infection with Mycobacterium tuberculosis.Methodology/Principal Findings
We first examined M. tuberculosis-specific IFN-γ and H. pylori antibody responses in 339 healthy Northern Californians undergoing routine tuberculin skin testing. Of 97 subjects (29%) meeting criteria for latent tuberculosis (TB) infection (LTBI), 45 (46%) were H. pylori seropositive. Subjects with LTBI who were H. pylori-seropositive had 1.5-fold higher TB antigen-induced IFN-γ responses (p = 0.04, ANOVA), and a more Th-1 like cytokine profile in peripheral blood mononuclear cells, compared to those who were H. pylori seronegative. To explore an association between H. pylori infection and clinical outcome of TB exposure, we evaluated H. pylori seroprevalence in baseline samples from two high risk TB case-contact cohorts, and from cynomolgus macaques experimentally challenged with M. tuberculosis. Compared to 513 household contacts who did not progress to active disease during a median 24 months follow-up, 120 prevalent TB cases were significantly less likely to be H. pylori infected (AOR: 0.55, 95% CI 0.0.36–0.83, p = 0.005), though seroprevalence was not significantly different from non-progressors in 37 incident TB cases (AOR: 1.35 [95% CI 0.63–2.9] p = 0.44). Cynomolgus macaques with natural H. pylori infection were significantly less likely to progress to TB 6 to 8 months after M. tuberculosis challenge (RR: 0.31 [95% CI 0.12–0.80], p = 0.04).Conclusions/Significance
H. pylori infection may induce bystander effects that modify the risk of active TB in humans and non-human primates. That immunity to TB may be enhanced by exposure to other microbial agents may have important implications for vaccine development and disease control. 相似文献1000.
Toxic but drank: gustatory aversive compounds induce post-ingestional malaise in harnessed honeybees