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2.
Identification of signals for systemic adaption of hormonal regulation would help to understand the crosstalk between cells and environmental cues contributing to growth, metabolic homeostasis and development. Physiological states are controlled by precise pulsatile hormonal release, including endocrine steroids in human and ecdysteroids in insects. We show in Drosophila that regulation of genes that control biosynthesis and signaling of the steroid hormone ecdysone, a central regulator of developmental progress, depends on the extracellular matrix protein Obstructor-A (Obst-A). Ecdysone is produced by the prothoracic gland (PG), where sensory neurons projecting axons from the brain integrate stimuli for endocrine control. By defining the extracellular surface, Obst-A promotes morphogenesis and axonal growth in the PG. This process requires Obst-A-matrix reorganization by Clathrin/Wurst-mediated endocytosis. Our data identifies the extracellular matrix as essential for endocrine ring gland function, which coordinates physiology, axon morphogenesis, and developmental programs. As Obst-A and Wurst homologs are found among all arthropods, we propose that this mechanism is evolutionary conserved. 相似文献
3.
Matías Alejandro Molina Ailén Magalí Díaz Christina Hesse Wiebke Ginter María Virginia Gentilini Guillermo Gabriel Nu?ez Andrea Mercedes Canellada Tim Sparwasser Luciana Berod Marisa Silvia Castro Marcela Alejandra Manghi 《PloS one》2015,10(5)
Probiotics can modulate the immune system, conferring beneficial effects on the host. Understanding how these microorganisms contribute to improve the health status is still a challenge. Previously, we have demonstrated that Enterococcus faecalis CECT7121 implants itself and persists in the murine gastrointestinal tract, and enhances and skews the profile of cytokines towards the Th1 phenotype in several biological models. Given the importance of dendritic cells (DCs) in the orchestration of immunity, the aim of this work was to elucidate the influence of E. faecalis CECT7121 on DCs and the outcome of the immune responses. In this work we show that E. faecalis CECT7121 induces a strong dose-dependent activation of DCs and secretion of high levels of IL-12, IL-6, TNFα, and IL-10. This stimulation is dependent on TLR signaling, and skews the activation of T cells towards the production of IFNγ. The influence of this activation in the establishment of Th responses in vivo shows the accumulation of specific IFNγ-producing cells. Our findings indicate that the activation exerted by E. faecalis CECT7121 on DCs and its consequence on the cellular adaptive immune response may have broad therapeutic implications in immunomodulation. 相似文献
4.
E. Hesse A. Best M. Boots A. R. Hall A. Buckling 《Journal of evolutionary biology》2015,28(9):1682-1690
Abiotic environmental heterogeneity can promote the evolution of diverse resource specialists, which in turn may increase the degree of host–parasite specialization. We coevolved Pseudomonas fluorescens and lytic phage ?2 in spatially structured populations, each consisting of two interconnected subpopulations evolving in the same or different nutrient media (homogeneous and heterogeneous environments, respectively). Counter to the normal expectation, host–parasite specialization was significantly lower in heterogeneous compared with homogeneous environments. This result could not be explained by dispersal homogenizing populations, as this would have resulted in the heterogeneous treatments having levels of specialization equal to or greater than that of the homogeneous environments. We argue that selection for costly generalists is greatest when the coevolving species are exposed to diverse environmental conditions and that this can provide an explanation for our results. A simple coevolutionary model of this process suggests that this can be a general mechanism by which environmental heterogeneity can reduce rather than increase host–parasite specialization. 相似文献
5.
Christoph Ott Henrik Martens Imam Hassouna Bárbara Oliveira Christian Erck Maria-Patapia Zafeiriou Ulla-Kaisa Peteri D?rte Hesse Simone Gerhart Bekir Altas Tekla Kolbow Herbert Stadler Hiroshi Kawabe Wolfram-Hubertus Zimmermann Klaus-Armin Nave Walter Schulz-Schaeffer Olaf Jahn Hannelore Ehrenreich 《Molecular medicine (Cambridge, Mass.)》2015,21(1):803-815
Erythropoietin (EPO) exerts potent neuroprotective, neuroregenerative and procognitive functions. However, unequivocal demonstration of erythropoietin receptor (EPOR) expression in brain cells has remained difficult since previously available anti-EPOR antibodies (EPOR-AB) were unspecific. We report here a new, highly specific, polyclonal rabbit EPOR-AB directed against different epitopes in the cytoplasmic tail of human and murine EPOR and its characterization by mass spectrometric analysis of immuno-precipitated endogenous EPOR, Western blotting, immunostaining and flow cytometry. Among others, we applied genetic strategies including overexpression, Lentivirus-mediated conditional knockout of EpoR and tagged proteins, both on cultured cells and tissue sections, as well as intracortical implantation of EPOR-transduced cells to verify specificity. We show examples of EPOR expression in neurons, oligodendroglia, astrocytes and microglia. Employing this new EPOR-AB with double-labeling strategies, we demonstrate membrane expression of EPOR as well as its localization in intracellular compartments such as the Golgi apparatus. Moreover, we show injury-induced expression of EPOR. In mice, a stereotactically applied stab wound to the motor cortex leads to distinct EpoR expression by reactive GFAP-expressing cells in the lesion vicinity. In a patient suffering from epilepsy, neurons and oligodendrocytes of the hippocampus strongly express EPOR. To conclude, this new analytical tool will allow neuroscientists to pinpoint EPOR expression in cells of the nervous system and to better understand its role in healthy conditions, including brain development, as well as under pathological circumstances, such as upregulation upon distress and injury. 相似文献
6.
Ohne Zusammenfassung 相似文献
7.
P. R. Hesse 《Plant and Soil》1976,44(1):241-247
Summary An investigation has been made of the effects upon soil dispersion of different sized particles of gypsum and of methods of counteracting this effect. A final, recommended procedure for particle size determination in gypsic soils has been formulated and which depends upon the fact that treatment of gypsum crystals with barium chloride solution forms a protective coating of barium sulphate which isolates the gypsum from all further reaction in an alkaline medium. Satisfactory results have been obtained for soils containing up to over 90 percent gypsum, even if present in very fine particles of less than 0.05 mm.Food & Agriculture Organization of the United Nations 相似文献
8.
Soledad Galli Olaf Jahn Reiner Hitt Doerte Hesse Lennart Opitz Uwe Plessmann Henning Urlaub Juan Jose Poderoso Elizabeth A. Jares-Erijman Thomas M. Jovin 《PloS one》2009,4(10)
Extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) are members of the MAPK family and participate in the transduction of stimuli in cellular responses. Their long-term actions are accomplished by promoting the expression of specific genes whereas faster responses are achieved by direct phosphorylation of downstream effectors located throughout the cell. In this study we determined that hERK1 translocates to the mitochondria of HeLa cells upon a proliferative stimulus. In the mitochondrial environment, hERK1 physically associates with (i) at least 5 mitochondrial proteins with functions related to transport (i.e. VDAC1), signalling, and metabolism; (ii) histones H2A and H4; and (iii) other cytosolic proteins. This work indicates for the first time the presence of diverse ERK-complexes in mitochondria and thus provides a new perspective for assessing the functions of ERK1 in the regulation of cellular signalling and trafficking in HeLa cells. 相似文献
9.
Bernd Heimrich Daniel-Alexander Hesse Yuan-Ju Wu Sonja Schmid Martin Schwemmle 《Cell and tissue research》2009,338(2):179-190
Granule cells are major targets of entorhinal afferents terminating in a laminar fashion in the outer molecular layer of the
dentate gyrus. Since Borna disease virus (BDV) infection of newborn rats causes a progressive loss of granule cells in the
dentate gyrus, entorhinal fibres become disjoined from their main targets. We have investigated the extent to which entorhinal
axons react to this loss of granule cells. Unexpectedly, anterograde DiI tracing has shown a prominent layered termination
of the entorhinal projection, despite an almost complete loss of granule cells at 9 weeks after infection. Combined light-
and electron-microscopic analysis of dendrites at the outer molecular layer of the dentate gyrus at 6 and 9 weeks post-infection
has revealed a transient increase in the synaptic density of calbindin-positive granule cells and parvalbuminergic neurons
after 6 weeks. In contrast, synaptic density reaches values similar to those of uninfected controls 9 weeks post-infection.
These findings indicate that, after BDV infection, synaptic reorganization processes occur at peripheral dendrites of the
remaining granule cells and parvalbuminergic neurons, including the unexpected persistence of entorhinal axons in the absence
of their main targets. 相似文献
10.
Dmitri Demidov Susann Hesse Annegret Tewes Twan Rutten Jörg Fuchs Raheleh Karimi Ashtiyani Sandro Lein reas Fischer Gunter Reuter Andreas Houben 《The Plant journal : for cell and molecular biology》2009,59(2):221-230
The enzymological properties of AtAurora1, a kinase responsible for the cell cycle-dependent phosphorylation of histone H3 at S10, and its cross-talk with other post-translational histone modifications, were determined. In vitro phosphorylation of H3S10 by AtAurora1 is strongly increased by K9 acetylation, and decreased by K14 acetylation and T11 phosphorylation. However, S10 phosphorylation activity is unaltered by mono-, di- or trimethylation of K9. An interference of H3K9 dimethylation by SUVR4 occurs by a pre-existing phosphorylation at S10. Hence, cross-talk in plants exists between phosphorylation of H3S10 and methylation, acetylation or phosphorylation of neighbouring amino acid residues. AtAurora1 undergoes autophosphorylation in vivo regardless of the presence of substrate, and forms dimers in planta . Of the three ATP-competitive Aurora inhibitors tested, Hesperadin was most effective in reducing the in vivo kinase activity of AtAurora1. Hesperadin consistently inhibited histone H3S10 phosphorylation during mitosis in Arabidopsis cells, but did not affect other H3 post-translational modifications, suggesting a specific inhibition of AtAurora in vivo . Inactivation of AtAurora also caused lagging chromosomes in a number of anaphase cells, but, unlike the situation in mammalian cells, Hesperadin did not influence the microtubule dynamics in dividing cells. 相似文献