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141.
Silke Hauer 《Acta theriologica》2002,47(3):339-362
A sample of 1037 skulls of ottersLutra lutra (Linnaeus, 1758) from eastern Germany was analysed for inherent dental abnormalities. Deviations from the normal dental pattern
were found in 107 individuals. A total of 150 cases were classified in 5 categories of abnormality. In considering variations
from the normal number of teeth, supernumerary (polydonty, 1.7%) was more frequent than missing teeth (oligodonty, 0.9%).
In most cases, numerical variations were not connected with phylogenetic background. The most frequent variations were displacement
of teeth in the tooth row (6.0%) and deviations of the normal shape of teeth (3.3%). Variations of the local position of teeth
occurred in 2.6% of cases. None of these deviations showed significant sex-dependent differences. Furthermore, no regional
differences in the frequencies of these anomalies were noticed. Another 459 otters (822 cases) had accessory roots at P2,
P3, or P4. These characters were considered as non-metrical traits and used to study epigenetic regional differentiation.
The Mean Measure of Divergence segregated the Baltic coast from almost all other regions. Preliminary results of analysis
of Fluctuating Asymmetry are presented, using these traits to demonstrate the utility of dental deviations for estimating
influences on developmental stability. Generally, it can be stated that the dentition of otters is very stable. 相似文献
142.
143.
Here we identify the recruitment of solvent ions to lipid membranes as the dominant regulator of lipid phase behavior. Our data demonstrate that binding of counterions to charged lipids promotes the formation of lamellar membranes, whereas their absence can induce fusion. The mechanism applies to anionic and cationic liposomes, as well as the recently introduced amphoteric liposomes. In the latter, an additional pH-dependent lipid salt formation between anionic and cationic lipids must occur, as indicated by the depletion of membrane-bound ions in a zone around pH 5. Amphoteric liposomes fuse under these conditions but form lamellar structures at both lower and higher pH values. The integration of these observations into the classic lipid shape theory yielded a quantitative link between lipid and solvent composition and the physical state of the lipid assembly. The key parameter of the new model, κ(pH), describes the membrane phase behavior of charged membranes in response to their ion loading in a quantitative way. 相似文献
144.
145.
Minimal sample requirement for highly multiplexed protein quantification in cell lines and tissues by PCT‐SWATH mass spectrometry
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Shiying Shao Tiannan Guo Chiek Ching Koh Silke Gillessen Markus Joerger Wolfram Jochum Ruedi Aebersold 《Proteomics》2015,15(21):3711-3721
The amount of sample available for clinical and biological proteomic research is often limited and thus significantly restricts clinical and translational research. Recently, we have integrated pressure cycling technology (PCT) assisted sample preparation and SWATH‐MS to perform reproducible proteomic quantification of biopsy‐level tissue samples. Here, we further evaluated the minimal sample requirement of the PCT‐SWATH method using various types of samples, including cultured cells (HeLa, K562, and U251, 500 000 to 50 000 cells) and tissue samples (mouse liver, heart, brain, and human kidney, 3–0.2 mg). The data show that as few as 50 000 human cells and 0.2–0.5 mg of wet mouse and human tissues produced peptide samples sufficient for multiple SWATH‐MS analyses at optimal sample load applied to the system. Generally, the reproducibility of the method increased with decreasing tissue sample amounts. The SWATH maps acquired from peptides derived from samples of varying sizes were essentially identical based on the number, type, and quantity of identified peptides. In conclusion, we determined the minimal sample required for optimal PCT‐SWATH analyses, and found smaller sample size achieved higher quantitative accuracy. 相似文献
146.
Juliane Dinter Jessica Mühlhaus Carolin Leonie Wienchol Chun-Xia Yi Daniela Nürnberg Silke Morin Annette Grüters Josef K?hrle Torsten Sch?neberg Matthias Tsch?p Heiko Krude Gunnar Kleinau Heike Biebermann 《PloS one》2015,10(2)
ObjectiveApplication of 3-iodothyronamine (3-T1AM) results in decreased body temperature and body weight in rodents. The trace amine-associated receptor (TAAR) 1, a family A G protein-coupled receptor, is a target of 3-T1AM. However, 3-T1AM effects still persist in mTaar1 knockout mice, which suggest so far unknown further receptor targets that are of physiological relevance. TAAR5 is a highly conserved TAAR subtype among mammals and we here tested TAAR5 as a potential 3-T1AM target. First, we investigated mouse Taar5 (mTaar5) expression in several brain regions of the mouse in comparison to mTaar1. Secondly, to unravel the full spectrum of signaling capacities, we examined the distinct Gs-, Gi/o-, G12/13-, Gq/11- and MAP kinase-mediated signaling pathways of mouse and human TAAR5 under ligand-independent conditions and after application of 3-T1AM. We found overlapping localization of mTaar1 and mTaar5 in the amygdala and ventromedial hypothalamus of the mouse brain. Second, the murine and human TAAR5 (hTAAR5) display significant basal activity in the Gq/11 pathway but show differences in the basal activity in Gs and MAP kinase signaling. In contrast to mTaar5, 3-T1AM application at hTAAR5 resulted in significant reduction in basal IP3 formation and MAP kinase signaling. In conclusion, our data suggest that the human TAAR5 is a target for 3-T1AM, exhibiting inhibitory effects on IP3 formation and MAP kinase signaling pathways, but does not mediate Gs signaling effects as observed for TAAR1. This study also indicates differences between TAAR5 orthologs with respect to their signaling profile. In consequence, 3-T1AM-mediated effects may differ between rodents and humans. 相似文献
147.
William Heard Jan Sklená? Daniel F. A. Tomé Silke Robatzek Alexandra M. E. Jones 《Molecular & cellular proteomics : MCP》2015,14(7):1796-1813
The cell''s endomembranes comprise an intricate, highly dynamic and well-organized system. In plants, the proteins that regulate function of the various endomembrane compartments and their cargo remain largely unknown. Our aim was to dissect subcellular trafficking routes by enriching for partially overlapping subpopulations of endosomal proteomes associated with endomembrane markers. We selected RABD2a/ARA5, RABF2b/ARA7, RABF1/ARA6, and RABG3f as markers for combinations of the Golgi, trans-Golgi network (TGN), early endosomes (EE), secretory vesicles, late endosomes (LE), multivesicular bodies (MVB), and the tonoplast. As comparisons we used Golgi transport 1 (GOT1), which localizes to the Golgi, clathrin light chain 2 (CLC2) labeling clathrin-coated vesicles and pits and the vesicle-associated membrane protein 711 (VAMP711) present at the tonoplast. We developed an easy-to-use method by refining published protocols based on affinity purification of fluorescent fusion constructs to these seven subcellular marker proteins in Arabidopsis thaliana seedlings. We present a total of 433 proteins, only five of which were shared among all enrichments, while many proteins were common between endomembrane compartments of the same trafficking route. Approximately half, 251 proteins, were assigned to one enrichment only. Our dataset contains known regulators of endosome functions including small GTPases, SNAREs, and tethering complexes. We identify known cargo proteins such as PIN3, PEN3, CESA, and the recently defined TPLATE complex. The subcellular localization of two GTPase regulators predicted from our enrichments was validated using live-cell imaging. This is the first proteomic dataset to discriminate between such highly overlapping endomembrane compartments in plants and can be used as a general proteomic resource to predict the localization of proteins and identify the components of regulatory complexes and provides a useful tool for the identification of new protein markers of the endomembrane system.Membrane compartmentalization is an essential mechanism for eukaryotic life, by which cells separate and control biological processes. Plant growth, development, and adaptation to biotic and abiotic stress all rely on the highly dynamic endomembrane system, yet we know comparatively little about the proteins regulating these dynamic trafficking events. The plasma membrane (PM) provides the main interface between the cell and its environment, mediating the transfer of material to and from the cell and is a primary site for perception of external signals. Transmembrane proteins are synthesized in the endoplasmic reticulum (ER) and trafficked to the PM via the Golgi, although there are other secretory routes for soluble cargo (discussed in (1–4)). Post-Golgi trafficking is the main route by which newly synthesized transmembrane proteins and cell wall glycans are delivered to the PM. In plants, secretory and endocytic traffic converge at the trans-Golgi network (TGN), which also functions as an early endosome (EE). Multivesicular bodies (MVBs) are the other main endosomal compartment in plants and serve as prevacuolar compartments (PVCs) or late endosomes (LE) destined for vacuolar degradation (reviewed (1, 5, 6)).Recycling and sorting of plasma membrane proteins is essential for generating the polar localization of auxin efflux transporters (discussed in (7)), formation of the cell plate during cell division (8–11), and in defense such as localized deposition of papilla reviewed in (12, 13). Furthermore, the subcellular localization of transporters and receptors is dynamically regulated. For example, the boron transporter (BOR1) exhibits polar localization and is internalized and degraded under conditions of high boron to reduce toxicity (14, 15). Similarly the receptor-like kinases (RLKs) flagellin-sensing 2 (FLS2) and brassinosteroid insensitive 1 (BRI1), important transmembrane receptors in antibacterial immunity and plant development, respectively, are constitutively endocytosed and recycled to the PM (16–18). Both receptors and transporters are also cargoes of the LE/MVB trafficking route (16) and are probably sorted to the vacuole for degradation (19, 20). Importantly, FLS2 trafficking via the recycling endocytic or the late endocytic route depends on its activation status; inactive receptors are recycled while ligand-activated receptors are sorted to the late endosomal pathway (16). Similarly, the polar sorting of auxin efflux transporters depends on their phosphorylation status (21). These observations illustrate that membrane compartmentalization underpins important aspects of plant cell biology and has initiated a quest toward a better understanding of the endomembrane compartments and the routes and mechanisms by which cargo is trafficked and sorted within the cell.Membrane trafficking within the cell requires complex machinery consisting of a plethora of coat and adaptor proteins, small GTPases, targeting, tethering, and scission factors (reviewed in (22, 23)). Homologues of some animal and yeast and endomembrane regulators have been identified in plants, but the localization and function of many of these remain to be characterized. For example, members of the RAB GTPase family have been shown to have markedly different roles and localizations in plants compared with their animal and yeast homologs (24). Therefore, acquiring localization data for tethering complexes and other regulators in plant systems is essential. In Arabidopsis thaliana, some of these proteins have been developed as useful probes to visualize the different endomembrane compartments by fusion with fluorescent reporters (9, 25–27). These include regulators of trafficking events such as RAB GTPases that are molecular switches responsible for the assembly of tethering and docking complexes and compartment identity. RAB proteins are widely used markers of endomembrane compartments, for example RABD2a/ARA5 labels the Golgi and TGN/EE as well as post-Golgi vesicles (4, 24, 26, 28), RABF2b/ARA7 localizes to TGN/EE and LE (25), RABF1/ARA6 is a marker of the LE/MVB vesicles (25, 29), and RABG3f localizes to MVBs and the tonoplast (26, 30).Fluorescent-tagged marker lines for the live-cell imaging of plant cells have been invaluable in defining the location of proteins within and between organelles and endomembrane compartments (26). However, microscopic investigation of membrane trafficking is limited by throughput, as only few proteins can be studied simultaneously. A powerful approach to large-scale identification of proteins in endomembrane compartments is through subcellular fractionation based on physical properties to directly isolate or enrich for the subcellular compartment of interest. Subcellular fractionation-based proteomics have been successfully used to decipher the steady state and cargo proteomes of, including but not limited to, the ER, the vacuole, PM, mitochondria and chloroplasts, and smaller vesicle-like compartments such as peroxisomes and Golgi (31–41). However, the smaller, transitory vesicles of the secretory and endocytic pathways have proved challenging to purify for reliable proteomic analysis. To overcome this, affinity purification of vesicles was established in animal cells (42, 43) and recently successfully applied in plants in combination with subcellular fractionation. Affinity purification and mass spectrometry (MS) of syntaxin of plants 61 (SYP61)-positive TGN/EE compartments identified 145 proteins specifically enriched in (44), while affinity isolation of VHA-a1-GFP (vacuolar H+ ATPase A1) identified 105 proteins associated with the TGN/EE (45). The VHA-A1 affinity purification data were then further refined using density gradient centrifugation to differentiate cargo and steady-state proteins (45).We have further explored affinity purification of fluorescent-tagged markers localizing to defined compartments to identify proteins associated with trafficking. Our motivation was to dissect the trafficking routes by enriching for partially overlapping subpopulations of endosomal proteomes associated with small GTPases in the RAB family. We selected RABD2a/ARA5, RABF2b/ARA7, RABF1/ARA6, and RABG3f as markers for Golgi/TGN/EE/secretory vesicles, LE/MVB compartments, LE/MVB compartments and LE/MVB/tonoplast, respectively. Additionally, we used Golgi transport 1 (GOT1), which localizes to the Golgi, clathrin light chain 2 (CLC2) labeling clathrin-coated vesicles (CCVs) and pits and the vesicle-associated membrane protein 711 (VAMP711) present at the tonoplast (26, 27, 29, 46, 47) as comparisons. Our objective was to identify transient cargo proteins, tethers, and docking factors associated with dynamic subdomains of the endomembrane system, to supplement better-characterized “steady-state” components, and to identify components of recycling and vacuolar trafficking pathways. 相似文献
148.
Silke Bender Antje Reuter Florian Eberle Evelyne Einhorn Marco Binder Ralf Bartenschlager 《PLoS pathogens》2015,11(11)
Sensing viruses by pattern recognition receptors (PRR) triggers the innate immune system of the host cell and activates immune signaling cascades such as the RIG-I/IRF3 pathway. Mitochondrial antiviral-signaling protein (MAVS, also known as IPS-1, Cardif, and VISA) is the crucial adaptor protein of this pathway localized on mitochondria, peroxisomes and mitochondria-associated membranes of the endoplasmic reticulum. Activation of MAVS leads to the production of type I and type III interferons (IFN) as well as IFN stimulated genes (ISGs). To refine the role of MAVS subcellular localization for the induction of type I and III IFN responses in hepatocytes and its counteraction by the hepatitis C virus (HCV), we generated various functional and genetic knock-out cell systems that were reconstituted to express mitochondrial (mito) or peroxisomal (pex) MAVS, exclusively. Upon infection with diverse RNA viruses we found that cells exclusively expressing pexMAVS mounted sustained expression of type I and III IFNs to levels comparable to cells exclusively expressing mitoMAVS. To determine whether viral counteraction of MAVS is affected by its subcellular localization we employed infection of cells with HCV, a major causative agent of chronic liver disease with a high propensity to establish persistence. This virus efficiently cleaves MAVS via a viral protease residing in its nonstructural protein 3 (NS3) and this strategy is thought to contribute to the high persistence of this virus. We found that both mito- and pexMAVS were efficiently cleaved by NS3 and this cleavage was required to suppress activation of the IFN response. Taken together, our findings indicate comparable activation of the IFN response by pex- and mitoMAVS in hepatocytes and efficient counteraction of both MAVS species by the HCV NS3 protease. 相似文献
149.
Merima Bublin Maria Kostadinova Julian E. Fuchs Daniela Ackerbauer Adolfo H. Moraes Fabio C. L. Almeida Nina Lengger Christine Hafner Christof Ebner Christian Radauer Klaus R. Liedl Ana Paula Valente Heimo Breiteneder 《PloS one》2015,10(11)
Fish allergy is associated with moderate to severe IgE-mediated reactions to the calcium binding parvalbumins present in fish muscle. Allergy to multiple fish species is caused by parvalbumin-specific cross-reactive IgE recognizing conserved epitopes. In this study, we aimed to produce cross-reactive single chain variable fragment (scFv) antibodies for the detection of parvalbumins in fish extracts and the identification of IgE epitopes. Parvalbumin-specific phage clones were isolated from the human ETH-2 phage display library by three rounds of biopanning either against cod parvalbumin or by sequential biopanning against cod (Gad m 1), carp (Cyp c 1) and rainbow trout (Onc m 1) parvalbumins. While biopanning against Gad m 1 resulted in the selection of clones specific exclusively for Gad m 1, the second approach resulted in the selection of clones cross-reacting with all three parvalbumins. Two clones, scFv-gco9 recognizing all three parvalbumins, and scFv-goo8 recognizing only Gad m 1 were expressed in the E. coli non-suppressor strain HB2151 and purified from the periplasm. scFv-gco9 showed highly selective binding to parvalbumins in processed fish products such as breaded cod sticks, fried carp and smoked trout in Western blots. In addition, the scFv-gco9-AP produced as alkaline phosphatase fusion protein, allowed a single-step detection of the parvalbumins. In competitive ELISA, scFv-gco9 was able to inhibit binding of IgE from fish allergic patients’ sera to all three β-parvalbumins by up to 80%, whereas inhibition by scFv-goo8 was up to 20%. 1H/15N HSQC NMR analysis of the rGad m 1:scFv-gco9 complex showed participation of amino acid residues conserved among these three parvalbumins explaining their cross-reactivity on a molecular level. In this study, we have demonstrated an approach for the selection of cross-reactive parvalbumin-specific antibodies that can be used for allergen detection and for mapping of conserved epitopes. 相似文献
150.
Silke Andrich Burkhard Haastert Elke Neuhaus Kathrin Neidert Werner Arend Christian Ohmann Jürgen Grebe Andreas Vogt Pascal Jungbluth Grit R?sler Joachim Windolf Andrea Icks 《PloS one》2015,10(9)
Epidemiological data about pelvic fractures are limited. Until today, most studies only analyzed inpatient data. The purpose of this study was to estimate incidence rates of pelvic fractures in the German population aged 60 years or older, based on outpatient and inpatient data. We conducted a retrospective population-based observational study based on routine data from a large health insurance company in Germany. Age and sex-specific incidence rates of first fractures between 2008 and 2011 were calculated. We also standardized incidence rates with respect to age and sex in the German population. Multiple Poisson regression models were used to evaluate the association between the risk of first pelvic fracture as outcome and sex, age, calendar year and region as independent variables. The total number of patients with a first pelvic fracture corresponded to 8,041 and during the study period 5,978 insured persons needed inpatient treatment. Overall, the standardized incidence rate of all first pelvic fractures was 22.4 [95% CI 22.0–22.9] per 10,000 person-years, and the standardized incidence rate of inpatient treated fractures 16.5 [16.1–16.9]. Our adjusted regression analysis confirmed a significant sex (RR 2.38 [2.23–2.55], p < 0.001, men as reference) and age effect (higher risk with increasing age, p < 0.001) on first fracture risk. We found a slight association between calendar year (higher risk in later years compared to 2008, p = 0.0162) and first fracture risk and a further significant association with region (RR 0.92 [0.87–0.98], p = 0.006, Westfalen-Lippe as reference). The observed incidences are considerably higher than incidences described in the international literature, even if only inpatient treated pelvic fractures are regarded. Besides which, non-inclusion of outpatient data means that a relevant proportion of pelvic fractures are not taken into account. Prevention of low energy trauma among older people remains an important issue. 相似文献