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991.
N von Neuhoff T Oumeraci T Wolf K Kollewe P Bewerunge B Neumann B Brors J Bufler U Wurster B Schlegelberger R Dengler M Zapatka S Petri 《PloS one》2012,7(9):e44401
Background
Amyotrophic lateral sclerosis (ALS) is a fatal disorder of the motor neuron system with poor prognosis and marginal therapeutic options. Current clinical diagnostic criteria are based on electrophysiological examination and exclusion of other ALS-mimicking conditions. Neuroprotective treatments are, however, most promising in early disease stages. Identification of disease-specific CSF biomarkers and associated biochemical pathways is therefore most relevant to monitor disease progression, response to neuroprotective agents and to enable early inclusion of patients into clinical trials.Methods and Findings
CSF from 35 patients with ALS diagnosed according to the revised El Escorial criteria and 23 age-matched controls was processed using paramagnetic bead chromatography for protein isolation and subsequently analyzed by MALDI-TOF mass spectrometry. CSF protein profiles were integrated into a Random Forest model constructed from 153 mass peaks. After reducing this peak set to the top 25%, a classifier was built which enabled prediction of ALS with high accuracy, sensitivity and specificity. Further analysis of the identified peptides resulted in a panel of five highly sensitive ALS biomarkers. Upregulation of secreted phosphoprotein 1 in ALS-CSF samples was confirmed by univariate analysis of ELISA and mass spectrometry data. Further quantitative validation of the five biomarkers was achieved in an 80-plex Multiple Reaction Monitoring mass spectrometry assay.Conclusions
ALS classification based on the CSF biomarker panel proposed in this study could become a valuable predictive tool for early clinical risk stratification. Of the numerous CSF proteins identified, many have putative roles in ALS-related metabolic processes, particularly in chromogranin-mediated secretion signaling pathways. While a stand-alone clinical application of this classifier will only be possible after further validation and a multicenter trial, it could be readily used to complement current ALS diagnostics and might also provide new insights into the pathomechanisms of this disease in the future. 相似文献992.
James Cockram Thomas Thiel Burkhard Steuernagel Nils Stein Stefan Taudien Paul C. Bailey Donal M. O'Sullivan 《PloS one》2012,7(9)
Numerous CCT domain genes are known to control flowering in plants. They belong to the CONSTANS-like (COL) and PREUDORESPONSE REGULATOR (PRR) gene families, which in addition to a CCT domain possess B-box or response-regulator domains, respectively. Ghd7 is the most recently identified COL gene to have a proven role in the control of flowering time in the Poaceae. However, as it lacks B-box domains, its inclusion within the COL gene family, technically, is incorrect. Here, we show Ghd7 belongs to a larger family of previously uncharacterized Poaceae genes which possess just a single CCT domain, termed here CCT MOTIF FAMILY (CMF) genes. We molecularly describe the CMF (and related COL and PRR) gene families in four sequenced Poaceae species, as well as in the draft genome assembly of barley (Hordeum vulgare). Genetic mapping of the ten barley CMF genes identified, as well as twelve previously unmapped HvCOL and HvPRR genes, finds the majority map to colinear positions relative to their Poaceae orthologues. Combined inter-/intra-species comparative and phylogenetic analysis of CMF, COL and PRR gene families indicates they evolved prior to the monocot/dicot divergence ∼200 mya, with Poaceae CMF evolution described as the interplay between whole genome duplication in the ancestral cereal, and subsequent clade-specific mutation, deletion and duplication events. Given the proven role of CMF genes in the modulation of cereals flowering, the molecular, phylogenetic and comparative analysis of the Poaceae CMF, COL and PRR gene families presented here provides the foundation from which functional investigation can be undertaken. 相似文献
993.
994.
Burgalossi A Jung S Man KN Nair R Jockusch WJ Wojcik SM Brose N Rhee JS 《Nature protocols》2012,7(7):1351-1365
Neurotransmitter release is triggered by membrane depolarization, Ca(2+) influx and Ca(2+) sensing by the release machinery, causing synaptic vesicle (SV) fusion with the plasma membrane. Interlinked is a complex membrane cycle in which vesicles are tethered to the release site, primed, fused and recycled. As many of these processes are Ca(2+) dependent and simultaneously occurring, it is difficult to dissect them experimentally. This problem can be partially circumvented by controlling synaptic Ca(2+) concentrations via UV photolysis of caged Ca(2+). We developed a culture protocol for Ca(2+) uncaging in small synapses on the basis of the generation of small glia cell islands with single neurons on top, which are sufficiently small to be covered with a UV-light flash. Neurons are loaded with the photolabile Ca(2+)-chelator nitrophenyl-EGTA and Ca(2+) indicators, and a UV flash is used to trigger Ca(2+)-uncaging and SV fusion. The protocol takes three weeks to complete and provides unprecedented insights into the mechanisms of transmitter release. 相似文献
995.
996.
A Gross N Hüsken J Schur L Raszeja I Ott N Metzler-Nolte 《Bioconjugate chemistry》2012,23(9):1764-1774
Labeling of peptide nucleic acids (PNA) with metallocene complexes is explored herein for the modulation of the analytical characteristics, as well as biological properties of PNA. The synthesis of the first ruthenocene-PNA conjugate with a dodecamer, mixed-sequence PNA is described, and its properties are compared to a ferrocene-labeled analogue as well as an acetylated, metal-free derivative. The synthetic characteristics, chemical stability, analytical and thermodynamic properties, and the interaction with cDNA were investigated. Furthermore, the cytotoxicity of the PNA conjugates is determined on HeLa, HepG2, and PT45 cell lines. Finally, the cellular uptake of the metal-containing PNAs was quantified by high-resolution continuum source atomic absorption spectrometry (HR-CS AAS). An unexpectedly high cellular uptake to final concentrations of 4.2 mM was observed upon incubation with 50 μM solutions of the ruthenocene-PNA conjugate. The ruthenocene label was shown to be an excellent label in all respects, which is also more stable than its ferrocene analogue. Because of its high stability, low toxicity, and the lack of a natural background of ruthenium, it is an ideal choice for bioanalytical purposes and possible medicinal and biological applications like, e.g., the development of gene-targeted drugs. 相似文献
997.
998.
Shahinnia F Druka A Franckowiak J Morgante M Waugh R Stein N 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(2):373-384
Spike density in barley is under the control of several major genes, as documented previously by genetic analysis of a number
of morphological mutants. One such class of mutants affects the rachis internode length leading to dense or compact spikes
and the underlying genes were designated dense spike (dsp). We previously delimited two introgressed genomic segments on chromosome 3H (21 SNP loci, 35.5 cM) and 7H (17 SNP loci,
20.34 cM) in BW265, a BC7F3 nearly isogenic line (NIL) of cv. Bowman as potentially containing the dense spike mutant locus dsp.ar, by genotyping 1,536 single nucleotide polymorphism (SNP) markers in both BW265 and its recurrent parent. Here, the gene
was allocated by high-resolution bi-parental mapping to a 0.37 cM interval between markers SC57808 (Hv_SPL14)–CAPSK06413 residing on the short and long arm at the genetic centromere of chromosome 7H, respectively. This region putatively
contains more than 800 genes as deduced by comparison with the collinear regions of barley, rice, sorghum and Brachypodium, Classical map-based isolation of the gene dsp.ar thus will be complicated due to the infavorable relationship of genetic to physical distances at the target locus. 相似文献
999.
Riccomagno MM Hurtado A Wang H Macopson JG Griner EM Betz A Brose N Kazanietz MG Kolodkin AL 《Cell》2012,149(7):1594-1606
Axon pruning and synapse elimination promote neural connectivity and synaptic plasticity. Stereotyped pruning of axons that originate in the hippocampal dentate gyrus (DG) and extend along the infrapyramidal tract (IPT) occurs during postnatal murine development by neurite retraction and resembles axon repulsion. The chemorepellent Sema3F is required for IPT axon pruning, dendritic spine remodeling, and repulsion of DG axons. The signaling events that regulate IPT axon pruning are not known. We find that inhibition of the small G protein Rac1 by the Rac GTPase-activating protein (GAP) β2-Chimaerin (β2Chn) mediates Sema3F-dependent pruning. The Sema3F receptor neuropilin-2 selectively binds β2Chn, and ligand engagement activates this GAP to ultimately restrain Rac1-dependent effects on cytoskeletal reorganization. β2Chn is necessary for axon pruning both in vitro and in vivo, but it is dispensable for axon repulsion and spine remodeling. Therefore, a Npn2/β2Chn/Rac1 signaling axis distinguishes DG axon pruning from the effects of Sema3F on repulsion and dendritic spine remodeling. 相似文献
1000.
Halt AR Dallapiazza RF Zhou Y Stein IS Qian H Juntti S Wojcik S Brose N Silva AJ Hell JW 《The EMBO journal》2012,31(5):1203-1216
Memory is essential for our normal daily lives and our sense of self. Ca(2+) influx through the NMDA-type glutamate receptor (NMDAR) and the ensuing activation of the Ca(2+) and calmodulin-dependent protein kinase (CaMKII) are required for memory formation and its physiological correlate, long-term potentiation (LTP). The Ca(2+) influx induces CaMKII binding to the NMDAR to strategically recruit CaMKII to synapses that are undergoing potentiation. We generated mice with two point mutations that impair CaMKII binding to the NMDAR GluN2B subunit. Ca(2+)-triggered postsynaptic accumulation is largely abrogated for CaMKII and destabilized for TARPs, which anchor AMPA-type glutamate receptors (AMPAR). LTP is reduced by 50% and phosphorylation of the AMPAR GluA1 subunit by CaMKII, which enhances AMPAR conductance, impaired. The mutant mice learn the Morris water maze (MWM) as well as WT but show deficiency in recall during the period of early memory consolidation. Accordingly, the activity-driven interaction of CaMKII with the NMDAR is important for recall of MWM memory as early as 24 h, but not 1-2 h, after training potentially due to impaired consolidation. 相似文献