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991.
Ryon Graf Simone Barbero Nadine Keller Lauren Chen Sean Uryu David Schlaepfer Dwayne Stupack 《Cell Adhesion & Migration》2013,7(4):362-369
Procaspase-8, the zymogen form of the apoptosis-initiator caspase-8, undergoes phosphorylation following integrin-mediated cell attachment to an extracellular matrix substrate. Concordant with cell attachment to fibronectin, a population of procaspase-8 becomes associated with a peripheral insoluble compartment that includes focal complexes and lamellar microfilaments. Phosphorylation of procaspase-8 both impairs its maturation to the proapoptotic form and can promote cell migration. Here we show that the cytoskeletal adaptor protein CrkL promotes caspase-8 recruitment to the peripheral spreading edge of cells, and that the catalytic domain of caspase-8 directly interacts with the SH2 domain of CrkL. We show that the interaction is abolished by shRNA-mediated silencing of Src, in Src-deficient MEFs, and by pharmacologic inhibitors of the kinase. The results provide insight into how tyrosine kinases may act to coordinate the suppression caspase-8 mediated apoptosis, while promoting cell invasion. 相似文献
992.
Daniele De Simone Lorella D’Amico Daniela Bressanin Emma Motta Tiziana Annesi 《Mycological Progress》2011,10(3):301-306
Thirteen isolates of Inonotus rickii/Ptychogaster cubensis, from different geographic provenances, were analyzed by sequencing ITS1, ITS 2 and 5,8S ribosomal RNA region. A phylogenetic
tree, also including sequences available in Genbank database, showed that the strains enclosed in this study fall into two
well-separated groups, one formed by isolates from Florida (USA) and the other one by isolates from Europe, Argentina and
China. Differences were also highlighted on the growth rate of mycelial cultures at different temperatures. In fact, although
the tested isolates generally attained the best growth at 30°C, isolates from Europe seem well adapted to higher temperatures
and went on growing at 40°C whilst the growth of isolates from Florida significantly decreased at 35°C. Since the teleomorph
I. rickii was never detected in Florida, and in this study noticeable differences were detected by analysis of ITS region, the existence
of two possible distinct species, not discriminated solely on the basis of morphological characters, could be suggested. 相似文献
993.
Simone Mohren Ralf Weiskirchen 《Biochemical and biophysical research communications》2009,379(4):1015-1020
We have demonstrated that gene polymorphisms within the N-terminal leader sequence of TGF-β1 contribute to the outcome of hepatic fibrogenesis. In addition, the polymorphism at codon 25 affects TGF-β1 production in peripheral blood leukocytes. Therefore, it is general assumed that these polymorphisms influence cellular secretion of this cytokine. In the present study, we analysed if this widespread hypothesis is true. We cloned FLAG-tagged CMV-driven human full-length TGF-β1 expression constructs of the different allelic variations (i.e. 10Leu/25Arg, 10Pro/25Pro and 10Pro/25Arg) and transfected them into the immortal hepatic stellate cell line LX-2 and Chinese Hamster Ovary cells. Surprisingly, the allelic variants carrying a proline either in codon 10 or 25 showed overall reduced expression as assessed by Western blot and quantitative ELISA. We conclude that the allelic variations within the signal sequence influence the expression and not secretion of TGF-β1. Detailed RNA structure prediction analysis further suggests that the individual variants form different secondary structures. 相似文献
994.
Gilgenkrantz S 《Médecine sciences : M/S》2004,20(11):1004-1008
During the evolution, sex determination occurred early. Sex determining factors were progressively isolated from other genes in sexual chromosomes, or gonosomes. Among vertebrates, evolution took two opposite pathways : in mammals, the system of XX:XY sex determination, with Y chromosome, induces male differentiation. In contrast, in birds, the system ZZ:ZW, with the W chromosome, induces female differentiation. But comparative studies show that the two pathways are not so simple. In the chicken as in the lower vertebrates, estrogens play a central role in gonadal sex differentiation. Several genes, show to be critical for mammalian determination, are also expressed in the chicken but their expression pattern differs, indicating functional plasticity. The W-linked female determinants remains still unknown. But comparative studies of the two pathways, with conserved and divergent elements, are broadening our understanding of sex determination. 相似文献
995.
Asmita Banerjee Sylvia Nürnberger Simone Hennerbichler Sabrina Riedl Christina M. A. P. Schuh Ara Hacobian Andreas Teuschl Johann Eibl Heinz Redl Susanne Wolbank 《Cell and tissue banking》2014,15(2):227-239
Human amniotic membrane (hAM) is a tissue containing cells with proven stem cell properties. In its decellularized form it has been successfully applied as nerve conduit biomaterial to improve peripheral nerve regeneration in injury models. We hypothesize that viable hAM without prior cell isolation can be differentiated towards the Schwann cell lineage to generate a possible alternative to commonly applied tissue engineering materials for nerve regeneration. For in vitro Schwann cell differentiation, biopsies of hAM of 8 mm diameter were incubated with a sequential order of neuronal induction and growth factors for 21 days and characterized for cellular viability and the typical glial markers glial fibrillary acidic protein (GFAP), S100β, p75 and neurotrophic tyrosine kinase receptor (NTRK) using immunohistology. The secretion of the neurotrophic factors brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) was quantified by ELISA. The hAM maintained high viability, especially under differentiation conditions (90.2 % ± 41.6 day 14; 80.0 % ± 44.5 day 21 compared to day 0). Both, BDNF and GDNF secretion was up-regulated upon differentiation. The fresh membrane stained positive for GFAP and p75 and NTRK, which was strongly increased after culture in differentiation conditions. Especially the epithelial layer within the membrane exhibited a change in morphology upon differentiation forming a multi-layered epithelium with intense accumulations of the marker proteins. However, S100β was expressed at equal levels and equal distribution in fresh and cultured hAM conditions. Viable hAM may be a promising alternative to present formulations used for peripheral nerve regeneration. 相似文献
996.
Species distribution modeling and molecular markers suggest longitudinal range shifts and cryptic northern refugia of the typical calcareous grassland species Hippocrepis comosa (horseshoe vetch)
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Martin Leipold Simone Tausch Peter Poschlod Christoph Reisch 《Ecology and evolution》2017,7(6):1919-1935
Calcareous grasslands belong to the most diverse, endangered habitats in Europe, but there is still insufficient information about the origin of the plant species related to these grasslands. In order to illuminate this question, we chose for our study the representative grassland species Hippocrepis comosa (Horseshoe vetch). Based on species distribution modeling and molecular markers, we identified the glacial refugia and the postglacial migration routes of the species to Central Europe. We clearly demonstrate that H. comosa followed a latitudinal and due to its oceanity also a longitudinal gradient during the last glacial maximum (LGM), restricting the species to southern refugia situated on the Peninsulas of Iberia, the Balkans, and Italy during the last glaciation. However, we also found evidence for cryptic northern refugia in the UK, the Alps, and Central Germany. Both species distribution modeling and molecular markers underline that refugia of temperate, oceanic species such as H. comosa must not be exclusively located in southern but also in western of parts of Europe. The analysis showed a distinct separation of the southern refugia into a western cluster embracing Iberia and an eastern group including the Balkans and Italy, which determined the postglacial recolonization of Central Europe. At the end of the LGM, H. comosa seems to have expanded from the Iberian refugium, to Central and Northern Europe, including the UK, Belgium, and Germany. 相似文献
997.
Marfè G De Martino L Filomeni G Di Stefano C Giganti MG Pagnini U Napolitano F Iovane G Ciriolo MR Salimei PS 《Journal of cellular biochemistry》2006,97(4):813-823
To investigate on the hypothetical presence of an antiapoptotic gene, we utilized the CODEHOP (COnsensus-DEgenerate Hybrid Oligonucleotide Primers) strategy amplifying unknown sequences from a background of genomic (bovine herpesvirus type-1) BHV-1 DNA. An alignment of carboxyl-terminal domains belonging to three proteins encoded by gamma34.5, MyD116 and GADD34 genes, was carried out to design degenerate PCR primers in highly conserved regions. This allowed the amplification of a 110 bp fragment. This fragment was subjected to automatic sequencing and DNA sequence analysis revealed that its position resided between the nt 14363 and the nt 14438 in bovine herpesvirus type-1 (BHV-1) Cooper strain sharing an identity of 86% (UL14). Transient transfections showed that UL14 protein is efficient in protecting MDBK and K562 cells from sorbitol induced apoptosis. The protein's anti-apoptotic function may derive from its heat shock protein-like properties. 相似文献
998.
In a batch cultivation of Pichia pastoris expressing Candida rugosa lipase 1 (CRL1), secretion of 200 microg lipase ml(-1) of culture was achieved in sorbitol-based medium. However, a large amount of recombinant protein was retained intracellularly throughout the fermentation, pointing to the transport step as a major bottleneck. Therefore a translational fusion with the green fluorescent protein (GFP) was constructed that was expressed and transported similarly to the native lipase and retained catalytic activity. This analytical tool enables a rapid monitoring of product localization and amount, based on GFP-associated fluorescence. 相似文献
999.
Cilia‐localized LKB1 regulates chemokine signaling,macrophage recruitment,and tissue homeostasis in the kidney
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Kamile Lukas Abhijeet P Todkar Manuel Knoll Toma A Yakulov Alexis Hofherr Oliver Kretz Martin Helmstädter Wilfried Reichardt Simone Braeg Tom Aschman Annette Merkle Dietmar Pfeifer Verónica I Dumit Marie‐Claire Gubler Roland Nitschke Tobias B Huber Fabiola Terzi Jörn Dengjel Florian Grahammer Michael Köttgen Hauke Busch Melanie Boerries Gerd Walz Antigoni Triantafyllopoulou E Wolfgang Kuehn 《The EMBO journal》2018,37(15)
Polycystic kidney disease (PKD) and other renal ciliopathies are characterized by cysts, inflammation, and fibrosis. Cilia function as signaling centers, but a molecular link to inflammation in the kidney has not been established. Here, we show that cilia in renal epithelia activate chemokine signaling to recruit inflammatory cells. We identify a complex of the ciliary kinase LKB1 and several ciliopathy‐related proteins including NPHP1 and PKD1. At homeostasis, this ciliary module suppresses expression of the chemokine CCL2 in tubular epithelial cells. Deletion of LKB1 or PKD1 in mouse renal tubules elevates CCL2 expression in a cell‐autonomous manner and results in peritubular accumulation of CCR2+ mononuclear phagocytes, promoting a ciliopathy phenotype. Our findings establish an epithelial organelle, the cilium, as a gatekeeper of tissue immune cell numbers. This represents an unexpected disease mechanism for renal ciliopathies and establishes a new model for how epithelial cells regulate immune cells to affect tissue homeostasis. 相似文献
1000.
Tinto N Zagari A Capuano M De Simone A Capobianco V Daniele G Giugliano M Spadaro R Franzese A Sacchetti L 《PloS one》2008,3(4):e1870