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1.
I. J. Pickering Graham N. George Verena Van Fleet-Stalder Thomas G. Chasteen Roger C. Prince 《Journal of biological inorganic chemistry》1999,4(6):791-794
Received: 2 April 1999 / Accepted: 17 September 1999 相似文献
2.
Jake V Bailey Verena Salman Gregory W Rouse Heide N Schulz-Vogt Lisa A Levin Victoria J Orphan 《The ISME journal》2011,5(12):1926-1935
We present evidence for a dimorphic life cycle in the vacuolate sulfide-oxidizing bacteria that appears to involve the attachment of a spherical Thiomargarita-like cell to the exteriors of invertebrate integuments and other benthic substrates at methane seeps. The attached cell elongates to produce a stalk-like form before budding off spherical daughter cells resembling free-living Thiomargarita that are abundant in surrounding sulfidic seep sediments. The relationship between the attached parent cell and free-living daughter cell is reminiscent of the dimorphic life modes of the prosthecate Alphaproteobacteria, but on a grand scale, with individual elongate cells reaching nearly a millimeter in length. Abundant growth of attached Thiomargarita-like bacteria on the integuments of gastropods and other seep fauna provides not only a novel ecological niche for these giant bacteria, but also for animals that may benefit from epibiont colonization. 相似文献
3.
Matthias Kirsch Mun-Yong Lee Verena Meyer Annette Wiese Hans-Dieter Hofmann 《Journal of neurochemistry》1997,68(3):979-990
Abstract: There is increasing, although largely indirect, evidence that neurotrophic factors not only function as target-derived survival factors for projection neurons, but also act locally to regulate developmental processes. We studied the expression of ciliary neurotrophic factor (CNTF) and the CNTF-specific ligand-binding α-subunit of the CNTF receptor complex (CNTFRα) in the rat retina, a well-defined CNS model system, and CNTF effects on cultured retinal neurons. Both CNTF and CNTFRα (mRNA and protein) are expressed during phases of retinal neurogenesis and differentiation. Retina-specific Müller glia are immunocytochemically identified as the site of CNTF production and CNTFRα-expressing, distinct neuronal cell types as potential CNTF targets. Biological effects on corresponding neurons in culture further support the conclusion that locally supplied CNTF plays a regulatory role in the development of various retinal cell types including ganglion cells and interneurons. 相似文献
4.
James E. Jumblatt Tien-Wen Tao Verena Schlup Jukka Finne Max M. Burger 《Biochemical and biophysical research communications》1980,95(1):111-117
Variants of B 16-F 1 mouse melanoma cells selected for resistance to wheat germ agglutinin (WGA) toxicity were found to have undergone a stable surface change correlated both to lectin resistance and reduced metastasizing potential. The surface alteration, as indicated by the increased electrophoretic mobilities of several lactoperoxidase-iodinated cell surface proteins in SDS-PAGE, was restricted to polypeptides able to interact with WGA. The availability of lectin-resistant melanoma cell variants having altered metastasizing behavior provides a promising approach to studies of the role of specific cell surface components in the metastasizing process. 相似文献
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6.
Receptor for advanced glycation end products is subjected to protein ectodomain shedding by metalloproteinases 总被引:1,自引:0,他引:1
Zhang L Bukulin M Kojro E Roth A Metz VV Fahrenholz F Nawroth PP Bierhaus A Postina R 《The Journal of biological chemistry》2008,283(51):35507-35516
The receptor for advanced glycation end products (RAGE) is a 55-kDa type I membrane glycoprotein of the immunoglobulin superfamily. Ligand-induced up-regulation of RAGE is involved in various pathophysiological processes, including late diabetic complications and Alzheimer disease. Application of recombinant soluble RAGE has been shown to block RAGE-mediated pathophysiological conditions. After expression of full-length RAGE in HEK cells we identified a 48-kDa soluble RAGE form (sRAGE) in the culture medium. This variant of RAGE is smaller than a 51-kDa soluble version derived from alternative splicing. The release of sRAGE can be induced by the phorbol ester PMA and the calcium ionophore calcimycin via calcium-dependent protein kinase C subtypes. Hydroxamic acid-based metalloproteinase inhibitors block the release of sRAGE, and by RNA interference experiments we identified ADAM10 and MMP9 to be involved in RAGE shedding. In protein biotinylation experiments we show that membrane-anchored full-length RAGE is the precursor of sRAGE and that sRAGE is efficiently released from the cell surface. We identified cleavage of RAGE to occur close to the cell membrane. Ectodomain shedding of RAGE simultaneously generates sRAGE and a membrane-anchored C-terminal RAGE fragment (RAGE-CTF). The amount of RAGE-CTF increases when RAGE-expressing cells are treated with a gamma-secretase inhibitor, suggesting that RAGE-CTF is normally further processed by gamma-secretase. Identification of these novel mechanisms involved in regulating the availability of cell surface-located RAGE and its soluble ectodomain may influence further research in RAGE-mediated processes in cell biology and pathophysiology. 相似文献
7.
Elmar Porten Beate Seliger Verena A. Schneider Stefan W?ll Daniela Stangel Rene Ramseger Stephan Kr?ger 《The Journal of biological chemistry》2010,285(5):3114-3125
Clustering or overexpression of the transmembrane form of the extracellular matrix proteoglycan agrin in neurons results in the formation of numerous highly motile filopodia-like processes extending from axons and dendrites. Here we show that similar processes can be induced by overexpression of transmembrane-agrin in several non-neuronal cell lines. Mapping of the process-inducing activity in neurons and non-neuronal cells demonstrates that the cytoplasmic part of transmembrane agrin is dispensable and that the extracellular region is necessary for process formation. Site-directed mutagenesis reveals an essential role for the loop between β-sheets 3 and 4 within the Kazal subdomain of the seventh follistatin-like domain of TM-agrin. An aspartic acid residue within this loop is critical for process formation. The seventh follistatin-like domain could be functionally replaced by the first and sixth but not by the eighth follistatin-like domain, demonstrating a functional redundancy among some follistatin-like domains of agrin. Moreover, a critical distance of the seventh follistatin-like domain to the plasma membrane appears to be required for process formation. These results demonstrate that different regions within the agrin protein are responsible for synapse formation at the neuromuscular junction and for process formation in central nervous system neurons and suggest a role for agrin''s follistatin-like domains in the developing central nervous system. 相似文献
8.
9.
Sarah K. Oettl Jana Gerstmeier Shafaat Y. Khan Katja Wiechmann Julia Bauer Atanas G. Atanasov Clemens Malainer Ezzat M. Awad Pavel Uhrin Elke H. Heiss Birgit Waltenberger Daniel Remias Johannes M. Breuss Joel Boustie Verena M. Dirsch Hermann Stuppner Oliver Werz Judith M. Rollinger 《PloS one》2013,8(10)
In vitro screening of 17 Alpine lichen species for their inhibitory activity against 5-lipoxygenase, microsomal prostaglandin E2 synthase-1 and nuclear factor kappa B revealed Cetrelia monachorum (Zahlbr.) W.L. Culb. & C.F. Culb. As conceivable source for novel anti-inflammatory compounds. Phytochemical investigation of the ethanolic crude extract resulted in the isolation and identification of 11 constituents, belonging to depsides and derivatives of orsellinic acid, olivetolic acid and olivetol. The two depsides imbricaric acid (4) and perlatolic acid (5) approved dual inhibitory activities on microsomal prostaglandin E2 synthase-1 (IC50 = 1.9 and 0.4 µM, resp.) and on 5-lipoxygenase tested in a cell-based assay (IC50 = 5.3 and 1.8 µM, resp.) and on purified enzyme (IC50 = 3.5 and 0.4 µM, resp.). Additionally, these two main constituents quantified in the extract with 15.22% (4) and 9.10% (5) showed significant inhibition of tumor necrosis factor alpha-induced nuclear factor kappa B activation in luciferase reporter cells with IC50 values of 2.0 and 7.0 µM, respectively. In a murine in vivo model of inflammation, 5 impaired the inflammatory, thioglycollate-induced recruitment of leukocytes to the peritoneum. The potent inhibitory effects on the three identified targets attest 4 and 5 a pronounced multi-target anti-inflammatory profile which warrants further investigation on their pharmacokinetics and in vivo efficacy. 相似文献
10.
Verena I. Carrara Khin Maung Lwin Aung Pyae Phyo Elizabeth Ashley Jacher Wiladphaingern Kanlaya Sriprawat Marcus Rijken Machteld Boel Rose McGready Stephane Proux Cindy Chu Pratap Singhasivanon Nicholas White Fran?ois Nosten 《PLoS medicine》2013,10(3)