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131.
Cilia‐localized LKB1 regulates chemokine signaling,macrophage recruitment,and tissue homeostasis in the kidney 下载免费PDF全文
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
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133.
Andrea Bolognesi Letizia Polito Fabiola Olivieri Paola Valbonesi Luigi Barbieri M. Giulia Battelli M. Vittoria Carusi Eugenio Benvenuto Francesca Del Vecchio Blanco Antimo Di Maro Augusto Parente Mario Di Loreto Fiorenzo Stirpe 《Planta》1997,203(4):422-429
New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10−10 M range, and by various cell lines, with IC50s in the 10−8–10−6 M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine
glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237–282) with
an LD50 (concentration that is 50% lethal) ≤ 8 mg · kg−1 body weight, whilst the RIP from Bougainvillea spectabilis had an LD50 >32 mg · kg−1. The N-terminal sequence of the two RIPs from Basella rubra had 80–93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst
the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.
Received: 5 March 1997 / Accepted: 27 May 1997 相似文献
134.
Radioimmunoassays capable of detecting pseudouridine, N2-dimethylguanosine, and 7-methylguanosine at picomole levels were developed. The antibodies to the nucleoside-human serum albumin conjugates recognize the modified ribose linked to the ?-amino group of lysine. The relative serological activities of the different nucleosides in the pseudouridine anti-pseudouridine-human serum albumin reaction depend upon the presence of the ribose ?-aminocaproate moiety in the radiolabeled antigen and/or the competing unlabeled nucleoside. 相似文献
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136.
Two new species of Phyllonema (Rivulariaceae,Cyanobacteria) with an emendation of the genus 下载免费PDF全文
Laura González‐Resendiz Jeffrey R. Johansen Viviana Escobar‐Sánchez Claudia Segal‐Kischinevzky Luis F. Jiménez‐García Hilda León‐Tejera 《Journal of phycology》2018,54(5):638-652
Two untapered, heterocytous species were observed and collected from the intertidal and supratidal zones of the Mexican coastline of the Pacific Ocean near Oaxaca and from the Gulf of Mexico. These populations were highly similar in morphology to the freshwater taxon Petalonema incrustans in the Scytonemataceae. However, 16S rRNA sequence data and phylogenetic analysis indicated that they were sister taxa to the epiphyllic, Brazilian species Phyllonema aveceniicola in the Rivulariaceae, described from culture material. While genetic identity between the two new species was high, they differed significantly in morphology, 16S rRNA gene sequence identity, and sequence and structure of the 16S–23S ITS region. Their morphology differed markedly from the generitype of the previously monotypic Phyllonema, which has tapered, heteropolar, single‐false branched trichomes with very thin or absent sheath. The two new species, Phyllonema ansata and Phyllonema tangolundensis, described from both culture and environmental material, have untapered, isopolar, geminately false branched trichomes with thick, lamellated sheaths, differences so significant that the species would not be placed in Phyllonema without molecular corroboration. The morphological differences are so significant that a formal emendation of the genus is required. These taxa provide a challenge to algal taxonomy because the morphological differences are such that one would logically conclude that they represent different genera, but the phylogenetic evidence for including them all in the same genus is conclusive. This conclusion is counter to the current trend in algal taxonomy in which taxa with minor morphological differences have been repeatedly placed in separate genera based primarily upon DNA sequence evidence. 相似文献
137.
Hilda Amiripour Babak Delnavaz Hashemloian Azra Ataei Azimi 《Acta Physiologiae Plantarum》2016,38(10):246
Rocket (Eruca sativa L.) is a medicinal plant that belongs to the Brassicaceae family and was reported to be a tolerant plant under soil salinity as well as high genetic diversity among its varieties. Since morphological and physiological changes to sodium sulfate stress toward this plant have not been investigated yet, the present study was implemented to assess the response of rocket (Eruca sativa L.) varieties to sodium sulfate (Na2SO4) stress as well as the relationship among these traits. Two varieties of rocket plants, the Iranian and Italian ones, were subjected to four salinity (Na2SO4) treatments [0 (control), 15, 30 and 60 mM of Na2SO4 solution] and three growth stages (49, 65, and 74 days) in factorial experiment with completely randomized design and three replications were considered. Some morphologic traits such as grain yield were measured during the growth period. The results of the analysis of variances between the mentioned variables indicated a significant difference between the varieties in terms of K+, Na+, Na+/K+, leaf length, grain yield, organic and mineral matter. The results of correlation and regression of the amounts of K+ showed a linear relationship with the grain yield and its variations were not independent from the variations of grain yield. Eventually, it seems that the Italian variety was more tolerant and having better performance in comparison with the Iranian variety, in response to salt stress. 相似文献
138.
Jochen Baßler Yasar Luqman Ahmed Martina Kallas Markus Kornprobst Fabiola R. Calviño Marén Gnädig Matthias Thoms Gunter Stier Sherif Ismail Satyavati Kharde Nestor Castillo Sabine Griesel Sonja Bastuck Bettina Bradatsch Emma Thomson Dirk Flemming Irmgard Sinning Ed Hurt 《Protein science : a publication of the Protein Society》2017,26(2):327-342
Ribosome biogenesis in eukaryotic cells is a highly dynamic and complex process innately linked to cell proliferation. The assembly of ribosomes is driven by a myriad of biogenesis factors that shape pre‐ribosomal particles by processing and folding the ribosomal RNA and incorporating ribosomal proteins. Biochemical approaches allowed the isolation and characterization of pre‐ribosomal particles from Saccharomyces cerevisiae, which lead to a spatiotemporal map of biogenesis intermediates along the path from the nucleolus to the cytoplasm. Here, we cloned almost the entire set (~180) of ribosome biogenesis factors from the thermophilic fungus Chaetomium thermophilum in order to perform an in‐depth analysis of their protein–protein interaction network as well as exploring the suitability of these thermostable proteins for structural studies. First, we performed a systematic screen, testing about 80 factors for crystallization and structure determination. Next, we performed a yeast 2‐hybrid analysis and tested about 32,000 binary combinations, which identified more than 1000 protein–protein contacts between the thermophilic ribosome assembly factors. To exemplary verify several of these interactions, we performed biochemical reconstitution with the focus on the interaction network between 90S pre‐ribosome factors forming the ctUTP‐A and ctUTP‐B modules, and the Brix‐domain containing assembly factors of the pre‐60S subunit. Our work provides a rich resource for biochemical reconstitution and structural analyses of the conserved ribosome assembly machinery from a eukaryotic thermophile. 相似文献
139.
Expansion strategies for human mesenchymal stromal cells culture under xeno‐free conditions 下载免费PDF全文
Patrícia Aparecida Tozetti Samia Rigotto Caruso Amanda Mizukami Taisa Risque Fernandes Fernanda Borges da Silva Fabiola Traina Dimas Tadeu Covas Maristela Delgado Orellana Kamilla Swiech 《Biotechnology progress》2017,33(5):1358-1367
Choosing the culture system and culture medium used to produce cells are key steps toward a safe, scalable, and cost‐effective expansion bioprocess for cell therapy purposes. The use of AB human serum (AB HS) as an alternative xeno‐free supplement for mesenchymal stromal cells (MSC) cultivation has increasingly gained relevance due to safety and efficiency aspects. Here we have evaluated different scalable culture systems to produce a meaningful number of umbilical cord matrix‐derived MSC (UCM MSC) using AB HS for culture medium supplementation during expansion and cryopreservation to enable a xeno‐free bioprocess. UCM MSC were cultured in a scalable planar (compact 10‐layer flasks and roller bottles) and 3‐D microcarrier‐based culture systems (spinner flasks and stirred tank bioreactor). Ten layer flasks and roller bottles enabled the production of 2.6 ± 0.6 × 104 and 1.4 ± 0.3 × 104 cells/cm2. UCM MSC‐based microcarrier expansion in the stirred conditions has enabled the production of higher cell densities (5.5–23.0 × 104 cells/cm2) when compared to planar systems. Nevertheless, due to the moderate harvesting efficiency attained, (80% for spinner flasks and 46.6% for bioreactor) the total cell number recovered was lower than expected. Cells maintained the functional properties after expansion in all the culture systems evaluated. The cryopreservation of cells (using AB HS) was also successfully carried out. Establishing scalable xeno‐free expansion processes represents an important step toward a GMP compliant large‐scale production platform for MSC‐based clinical applications. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1358–1367, 2017 相似文献
140.
Hilleringmann M Giusti F Baudner BC Masignani V Covacci A Rappuoli R Barocchi MA Ferlenghi I 《PLoS pathogens》2008,4(3):e1000026
Pili have been identified on the cell surface of Streptococcus pneumoniae, a major cause of morbidity and mortality worldwide. In contrast to Gram-negative bacteria, little is known about the structure of native pili in Gram-positive species and their role in pathogenicity. Triple immunoelectron microscopy of the elongated structure showed that purified pili contained RrgB as the major compound, followed by clustered RrgA and individual RrgC molecules on the pilus surface. The arrangement of gold particles displayed a uniform distribution of anti-RrgB antibodies along the whole pilus, forming a backbone structure. Antibodies against RrgA were found along the filament as particulate aggregates of 2-3 units, often co-localised with single RrgC subunits. Structural analysis using cryo electron microscopy and data obtained from freeze drying/metal shadowing technique showed that pili are oligomeric appendages formed by at least two protofilaments arranged in a coiled-coil, compact superstructure of various diameters. Using extracellular matrix proteins in an enzyme-linked immunosorbent assay, ancillary RrgA was identified as the major adhesin of the pilus. Combining the structural and functional data, a model emerges where the pilus RrgB backbone serves as a carrier for surface located adhesive clusters of RrgA that facilitates the interaction with the host. 相似文献