Characterization of TseB: A new actor in cell wall elongation in Bacillus subtilis.

Penicillin-binding proteins (PBPs) are crucial enzymes of peptidoglycan assembly and targets of β-lactam antibiotics. However, little is known about their regulation. Recently, membrane proteins were shown to regulate the bifunctional transpeptidases/glycosyltransferases aPBPs in some bacteria.

Epigenetic down-regulation of the HIST1 locus predicts better prognosis in acute myeloid leukemia with NPM1 mutation.

Background: The epigenetic machinery is frequently altered in acute myeloid leukemia. Focusing on cytogenetically normal (CN) AML, we previously described an abnormal H3K27me3 enrichment covering 70 kb on the HIST1 cluster (6.p22) in CN-AML patient blasts.

Differential modification of the C. elegans proteome in response to acute and chronic gamma radiation: Link with reproduction decline.

Emission of ionizing radiation (IR) in the environment is a natural phenomenon which can be enhanced by human activities. Ecosystems are then chronically exposed to IR. But environmental risk assessment of chronic exposure suffers from a lack of knowledge.

Development of parallel reaction monitoring (PRM)-based quantitative proteomics applied to HER2-Positive breast cancer.

Introduction: treatments targeting the Human Epidermal Growth Factor Receptor 2 (HER2/ERBB2) have improved the natural history of HER2-positive breast cancer. However, except HER2 protein expression and gene amplification, there is no predictive biomarker to guide the HER2-targeted therapies. We developed Parallel reaction monitoring (PRM) a powerful approach, to quantify and evaluate key proteins involved in the HER2 pathway and/or anti-HER2 treatment sensitivity.

Oxadiazolone derivatives, new promising multi-target inhibitors against M. tuberculosis.

A set of 19 oxadiazolone (OX) derivatives have been investigated for their antimycobacterial activity against two pathogenic slow-growing mycobacteria, Mycobacterium marinum and Mycobacterium bovis BCG, and the avirulent Mycobacterium tuberculosis (M. tb) mc6230. The encouraging minimal inhibitory concentrations (MIC) values obtained prompted us to test them against virulent M.

Septin 9_i2 is downregulated in tumors, impairs cancer cell migration and alters subnuclear actin filaments.

Functions of septin cytoskeletal polymers in tumorigenesis are still poorly defined. Their role in the regulation of cytokinesis and cell migration were proposed to contribute to cancer associated aneuploidy and metastasis. Overexpression of Septin 9 (Sept9) promotes migration of cancer cell lines.

Responses of the marine diatom Thalassiosira pseudonana to changes in CO concentration: a proteomic approach.

The concentration of CO in many aquatic systems is variable, often lower than the K of the primary carboxylating enzyme Rubisco, and in order to photosynthesize efficiently, many algae operate a facultative CO concentrating mechanism (CCM). Here we measured the responses of a marine diatom, Thalassiosira pseudonana, to high and low concentrations of CO at the level of transcripts, proteins and enzyme activity. Low CO caused many metabolic pathways to be remodeled.

Poly(ADP-ribose) polymerase 1 (PARP1) overexpression in human breast cancer stem cells and resistance to olaparib.

Background: Breast cancer stem cells (BCSCs) have been recognized as playing a major role in various aspects of breast cancer biology. To identify specific biomarkers of BCSCs, we have performed comparative proteomics of BCSC-enriched and mature cancer cell populations from the human breast cancer cell line (BCL), BrCA-MZ-01.

Methods: ALDEFLUOR assay was used to sort BCSC-enriched (ALDH+) and mature cancer (ALDH-) cell populations.

Kinetic analysis of mouse brain proteome alterations following Chikungunya virus infection before and after appearance of clinical symptoms.

Recent outbreaks of Chikungunya virus (CHIKV) infection have been characterized by an increasing number of severe cases with atypical manifestations including neurological complications. In parallel, the risk map of CHIKV outbreaks has expanded because of improved vector competence. These features make CHIKV infection a major public health concern that requires a better understanding of the underlying physiopathological processes for the development of antiviral strategies to protect individuals from severe disease.

Biochemical, transcriptional and translational evidences of the phenol-meta-degradation pathway by the hyperthermophilic Sulfolobus solfataricus 98/2.

Phenol is a widespread pollutant and a model molecule to study the biodegradation of monoaromatic compounds. After a first oxidation step leading to catechol in mesophilic and thermophilic microorganisms, two main routes have been identified depending on the cleavage of the aromatic ring: ortho involving a catechol 1,2 dioxygenase (C12D) and meta involving a catechol 2,3 dioxygenase (C23D). Our work aimed at elucidating the phenol-degradation pathway in the hyperthermophilic archaea Sulfolobus solfataricus 98/2.

The first genomic and proteomic characterization of a deep-sea sulfate reducer: insights into the piezophilic lifestyle of Desulfovibrio piezophilus.

Desulfovibrio piezophilus strain C1TLV30(T) is a piezophilic anaerobe that was isolated from wood falls in the Mediterranean deep-sea. D. piezophilus represents a unique model for studying the adaptation of sulfate-reducing bacteria to hydrostatic pressure.

Anopheles salivary gland proteomes from major malaria vectors.

Background: Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are species-specific is not entirely resolved. Thus, a better knowledge of the diversity among salivary protein repertoires from various malaria vector species is necessary to select relevant genus-, subgenus- and/or species-specific salivary antigens.

Identification of salivary antigenic markers discriminating host exposition between two European ticks: Rhipicephalus sanguineus and Dermacentor reticulatus.

To succeed blood meal, ticks inject salivary proteins to mammalian hosts, eliciting an antibody response against these foreign antigens. Although this immune response has been proposed as a surrogate marker of exposure to tick bites, identification of the corresponding antigens remains elusive. For this aim, a comparison by immunoblots of the kinetic IgG responses to protein salivary gland extracts from two European tick species, Rhipicephalus sanguineus or Dermacentor reticulatus, in rabbits was performed.

A UPR-independent infection-specific role for a BiP/GRP78 protein in the control of antimicrobial peptide expression in C. elegans epidermis.

The nematode C. elegans responds to infection by the fungus Drechmeria coniospora with a rapid increase in the expression of antimicrobial peptide genes. To investigate further the molecular basis of this innate immune response, we took a two-dimensional difference in-gel electrophoresis (2D-DIGE) approach to characterize the changes in host protein that accompany infection.

Proteomic analysis revealed alterations of the metabolism following salicylhydroxamic acid exposure.

Objectives: Although human respiratory metabolism is characterized by the mitochondrial electron transport chain, some organisms present a "branched respiratory chain." This branched pathway includes both a classical and an alternative respiratory chain. The latter involves an alternative oxidase.

Plasmodium falciparum infection-induced changes in erythrocyte membrane proteins.

Over the past decade, advances in proteomic and mass spectrometry techniques and the sequencing of the Plasmodium falciparum genome have led to an increasing number of studies regarding the parasite proteome. However, these studies have focused principally on parasite protein expression, neglecting parasite-induced variations in the host proteome. Here, we investigated P.

Global response of Plasmodium falciparum to hyperoxia: a combined transcriptomic and proteomic approach.

Background: Over its life cycle, the Plasmodium falciparum parasite is exposed to different environmental conditions, particularly to variations in O2 pressure. For example, the parasite circulates in human venous blood at 5% O2 pressure and in arterial blood, particularly in the lungs, at 13% O2 pressure. Moreover, the parasite is exposed to 21% O2 levels in the salivary glands of mosquitoes.

Specific antibody responses against membrane proteins of erythrocytes infected by Plasmodium falciparum of individuals briefly exposed to malaria.

Background: Plasmodium falciparum infections could lead to severe malaria, principally in non-immune individuals as children and travellers from countries exempted of malaria. Severe malaria is often associated with the sequestration of P. falciparum-infected erythrocytes in deep micro-vascular beds via interactions between host endothelial receptors and parasite ligands expressed on the surface of the infected erythrocyte.

The glyceraldehyde-3-phosphate dehydrogenase and the small GTPase Rab 2 are crucial for Brucella replication.

The intracellular pathogen Brucella abortus survives and replicates inside host cells within an endoplasmic reticulum (ER)-derived replicative organelle named the "Brucella-containing vacuole" (BCV). Here, we developed a subcellular fractionation method to isolate BCVs and characterize for the first time the protein composition of its replicative niche. After identification of BCV membrane proteins by 2 dimensional (2D) gel electrophoresis and mass spectrometry, we focused on two eukaryotic proteins: the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the small GTPase Rab 2 recruited to the vacuolar membrane of Brucella.

Antifungal innate immunity in C. elegans: PKCdelta links G protein signaling and a conserved p38 MAPK cascade.

Like other multicellular organisms, the model nematode C. elegans responds to infection by inducing the expression of defense genes. Among the genes upregulated in response to a natural fungal pathogen is nlp-29, encoding an antimicrobial peptide.

Cooperation between engulfment receptors: the case of ABCA1 and MEGF10.

The engulfment of dying cells is a specialized form of phagocytosis that is extremely conserved across evolution. In the worm, it is genetically controlled by two parallel pathways, which are only partially reconstituted in mammals. We focused on the recapitulation of the CED-1 defined pathway in mammalian systems.

ABCA2 is a marker of neural progenitors and neuronal subsets in the adult rodent brain.

The notion that the ATP-binding cassette transporter-A2 (ABCA2) may be involved in brain sterol homeostasis and is associated with early onset Alzheimer's disease led us to explore its neural expression. Our data support and extend the previous reports on ABCA2 expression by oligodendrocytes. They evidence that ABCA2 (i) is located in intracellular vesicles, identified in transfected cells as lysosome-related organelles only partially overlapping with classical endolysosomes; (ii) is a marker of neural progenitors as it is expressed in the subventricular zone of the lateral ventricle and the dentate gyrus of the hippocampal formation, sites of continual neurogenesis in the adult brain, and in nestin(+) cells differentiated in vitro from embryonic stem cells; (iii) persists, in the adult rodent brain, in a subset of GABAergic and glutamatergic neurons.

Involvement of brain endogenous cholecystokinin in stress-induced impairment of spatial recognition memory.

The central fragment of cholecystokinin, CCK8, plays a critical role in stress-related changes in behavior and memory. Therefore, we investigated whether the endogenous cholecystokininergic system is involved in the impairment of attention and/or memory induced by stressful conditions. Plasma corticosterone concentrations increased three-fold and plasma adrenocorticotropin (ACTH); concentrations increased five-fold when rats were maintained in the open arm of an elevated plus maze for 5 min.

A novel reporter strain to follow Cre-mediated recombination in T and NK cells.

The Cre-loxP system permits the generation of mouse models in which the fate of a cell can be followed through time. Such approach is of great value in immunology because it may allow lineage studies and the dissection of the contribution of specific effector T cells to long-term memory responses or autoimmune responses. An essential component of such a strategy is the development of appropriate reporter strains of mice in which the inducible reporter molecule is not immunogenic and is well expressed at the cell surface of T cells.

Deletion of CCK2 receptor in mice results in an upregulation of the endogenous opioid system.

Stimulation of the brain CCK2 receptor by the C-terminal octapeptide CCK8 of cholecystokinin (CCK) negatively modulates opioid responses. This suggests the existence of physiologically relevant interactions between endogenous CCK and opioid peptides, opening new perspectives particularly in the treatment of pain or drug addiction. CCK2 receptor-deficient mice were used to analyze the incidence of this gene invalidation on opioid system.