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101.
102.
Jackson Oyindamola Quilliam Richard S. Stott Andy Grant Helen Subke Jens-Arne 《Plant and Soil》2019,437(1-2):473-485
Plant and Soil - Root exudation is an important carbon (C) and energy source for soil microorganisms but quantifying its spatial distribution is challenging. We tested whether 14C imaging (analogue... 相似文献
103.
dm Lovas‐Kiss Marta I. Snchez David M. Wilkinson Neil E. Coughlan Jos A. Alves Andy J. Green 《Ecography》2019,42(5):956-967
Shorebirds (Charadriiformes) undergo rapid migrations with potential for long‐distance dispersal (LDD) of plants. We studied the frequency of endozoochory by shorebirds in different parts of Europe covering a broad latitudinal range and different seasons. We assessed whether plants dispersed conformed to morphological dispersal syndromes. A total of 409 excreta samples (271 faeces and 138 pellets) were collected from redshank Tringa totanus, black‐winged stilt Himantopus himantopus, pied avocet Recurvirostra avosetta, northern lapwing Vanellus vanellus, Eurasian curlew Numenius arquata and black‐tailed godwit Limosa limosa in south‐west Spain, north‐west England, southern Ireland and Iceland in 2005 and 2016, and intact seeds were extracted and identified. Godwits were sampled just before or after migratory movements between England and Iceland. The germinability of seeds was tested. Intact diaspores were recovered from all bird species and study areas, and were present in 13% of samples overall. Thirteen plant families were represented, including Charophyceae and 26 angiosperm taxa. Only four species had an ‘endozoochory syndrome’. Four alien species were recorded. Ellenberg values classified three species as aquatic and 20 as terrestrial. Overall, 89% of seeds were from terrestrial plants, and 11% from aquatic plants. Average seed length was higher in redshank pellets than in their faeces. Six species were germinated, none of which had an endozoochory syndrome. Seeds were recorded during spring and autumn migration. Plant species recorded have broad latitudinal ranges consistent with LDD via shorebirds. Crucially, morphological syndromes do not adequately predict LDD potential, and more empirical work is required to identify which plants are dispersed by shorebirds. Incorporating endozoochory by shorebirds and other migratory waterbirds into plant distribution models would allow us to better understand the natural processes that facilitated colonization of oceanic islands, or to improve predictions of how plants will respond to climate change, or how alien species spread. 相似文献
104.
Tom Z. Yuan Pankaj Garg Linya Wang Jordan R. Willis Eric Kwan Ana G Lujan Hernandez Emily Tuscano Emily N. Sever Erica Keane Cinque Soto Eric M. Mucker Mallorie E. Fouch Edgar Davidson Benjamin J. Doranz Shweta Kailasan M. Javad Aman Haoyang Li Jay W. Hooper Erica Ollmann Saphire James E. Crowe Qiang Liu Fumiko Axelrod Aaron K. Sato 《MABS-AUSTIN》2022,14(1)
105.
Nan Bai Kristin M. Riching Aman Makaju Hao Wu Timothy M. Acker Shu-Ching Ou Yaru Zhang Xiaomeng Shen Daryl N. Bulloch Huan Rui Bradford W. Gibson Danette L. Daniels Marjeta Urh Brooke M. Rock Sara C. Humphreys 《The Journal of biological chemistry》2022,298(4)
PROteolysis TArgeting Chimeras (PROTACs) are hetero-bifunctional small molecules that can simultaneously recruit target proteins and E3 ligases to form a ternary complex, promoting target protein ubiquitination and degradation via the Ubiquitin-Proteasome System (UPS). PROTACs have gained increasing attention in recent years due to certain advantages over traditional therapeutic modalities and enabling targeting of previously “undruggable” proteins. To better understand the mechanism of PROTAC-induced Target Protein Degradation (TPD), several computational approaches have recently been developed to study and predict ternary complex formation. However, mounting evidence suggests that ubiquitination can also be a rate-limiting step in PROTAC-induced TPD. Here, we propose a structure-based computational approach to predict target protein ubiquitination induced by cereblon (CRBN)-based PROTACs by leveraging available structural information of the CRL4A ligase complex (CRBN/DDB1/CUL4A/Rbx1/NEDD8/E2/Ub). We generated ternary complex ensembles with Rosetta, modeled multiple CRL4A ligase complex conformations, and predicted ubiquitination efficiency by separating the ternary ensemble into productive and unproductive complexes based on the proximity of the ubiquitin to accessible lysines on the target protein. We validated our CRL4A ligase complex models with published ternary complex structures and additionally employed our modeling workflow to predict ubiquitination efficiencies and sites of a series of cyclin-dependent kinases (CDKs) after treatment with TL12–186, a pan-kinase PROTAC. Our predictions are consistent with CDK ubiquitination and site-directed mutagenesis of specific CDK lysine residues as measured using a NanoBRET ubiquitination assay in HEK293 cells. This work structurally links PROTAC-induced ternary formation and ubiquitination, representing an important step toward prediction of target “degradability.” 相似文献
106.
Ian P. Holmes Richard J. Blunt Olivier E. Lorthioir Stephen M. Blowers Andy Gribble Andrew H. Payne Ian G. Stansfield Martyn Wood Patrick M. Woollard Charlie Reavill Claire M. Howes Fabrizio Micheli Romano Di Fabio Daniele Donati Silvia Terreni Dieter Hamprecht Luca Arista Angela Worby Steve P. Watson 《Bioorganic & medicinal chemistry letters》2010,20(6):2013-2016
The identification of a highly selective D2 partial agonist, D3 antagonist tool molecule which demonstrates high levels of brain exposure and selectivity against an extensive range of dopamine, serotonin, adrenergic, histamine, and muscarinic receptors is described. 相似文献
107.
Aman MJ Tosello-Trampont AC Ravichandran K 《The Journal of biological chemistry》2001,276(49):46371-46378
One type of membrane microdomain, enriched in glycosphingolipids and cholesterol and referred to as lipid rafts, has been implicated in the generation of activating signals triggered by a variety of stimuli. Several laboratories, including ours, have recently demonstrated that the B cell receptor (BCR) inducibly localizes to the rafts upon activation and that functional lipid rafts are important for BCR-mediated "positive" signaling. In the later phases of the immune response, coligation of the BCR and the inhibitory receptor Fc gamma RIIB1 leads to potent inhibition of BCR-induced positive signaling through the recruitment of the inositol phosphatase SHIP to Fc gamma RIIB1. One potential model is that the Fc gamma RIIB1 itself might be excluded from the rafts basally and that destabilization of raft-dependent BCR signaling might be part of the mechanism for the Fc gamma RIIB1-mediated negative regulation. We tested this hypothesis and observed that preventing BCR raft localization is not the mechanism for this inhibition. Surprisingly, a fraction of Fc gamma RIIB1 is constitutively localized in the rafts and increases further after BCR + FcR coligation. SHIP is actively recruited to lipid rafts under negative stimulation conditions, and the majority of Fc gamma RIIB1-SHIP complexes localize to lipid rafts compared with non-raft regions of the plasma membrane. This suggested that this negative feedback loop is also initiated in the lipid rafts. Despite its basal localization to the rafts, Fc gamma RIIB1 did not become phosphorylated after BCR alone cross-linking and did not colocalize with the BCR that moves to rafts upon BCR engagement alone (positive signaling conditions), perhaps suggesting the existence of different subsets of rafts. Taken together, these data suggest that lipid rafts play a role in both the positive signaling via the BCR as well as the inhibitory signaling through Fc gamma RIIB1/SHIP. 相似文献
108.
Staron RS Kraemer WJ Hikida RS Fry AC Murray JD Campos GE 《Histochemistry and cell biology》1999,111(2):117-123
The limb and trunk muscles of adult rats express four myosin heavy chain (MHC) isoforms, one slow (MHCI) and three fast (MHCIIa,
MHCIId, and MHCIIb). The distribution of these isoforms correlates with fiber types delineated using myofibrillar actomyosin
adenosine triphosphatase (mATPase) histochemistry. For example, type I fibers express MHCI and fiber types IIA, IID, and IIB
express MHCIIa, MHCIId, and MHCIIb, respectively. Fibers containing only one MHC isoform have been termed ”pure” fibers. Recent
evidence suggests that a population of ”hybrid” fibers exist in rat skeletal muscle which contain two MHC isoforms. The purpose
of the present investigation was to document the entire range of histochemically defined ”pure” and ”hybrid” fiber types in
untreated muscles of the young adult Fisher 344 rat hindlimb. The selected hindlimb muscles (soleus, tibialis anterior, extensor
digitorum longus, and gastrocnemius muscles) were removed from 12 male rats and analyzed for muscle fiber type distribution,
cross-sectional area, and MHC content. Care was taken to delineate eight fiber types (I, IC, IIC, IIA, IIAD, IID, IIDB, and
IIB) using refined histochemical techniques. Hybrid fibers were found to make up a considerable portion of the muscles examined
(a range of 8.8–17.8% of the total). The deep red portion of the gastrocnemius muscle contained the largest number of hybrid
fibers, most of which were the fast types IIAD (8.5±2.8%) and IIDB (5.2±2.3%). In conclusion, hybrid fibers make up a considerable
portion of normal rat limb musculature and are an important population that should not be ignored.
Accepted: 15 October 1998 相似文献
109.
Swenson DL Warfield KL Kuehl K Larsen T Hevey MC Schmaljohn A Bavari S Aman MJ 《FEMS immunology and medical microbiology》2004,40(1):27-31
Marburg virus (MARV), the causative agent of a severe hemorrhagic fever, has a characteristic filamentous morphology. Here we report that co-expression of MARV glycoprotein and matrix protein (VP40) in mammalian cells leads to spontaneous budding of filamentous particles strikingly similar to wild-type MARV. In addition, these particles elicit an immune response in BALB/c mice. The generation of non-replicating Marburg virus-like particles (VLPs) should significantly facilitate the research on molecular mechanisms of MARV assembly and release. Furthermore, VLPs may be an excellent vaccine candidate against Marburg infection. 相似文献
110.
Identification of a specific isoform of tomato lipoxygenase (TomloxC) involved in the generation of fatty acid-derived flavor compounds 总被引:14,自引:0,他引:14 下载免费PDF全文
There are at least five lipoxygenases (TomloxA, TomloxB, TomloxC, TomloxD, and TomloxE) present in tomato (Lycopersicon esculentum Mill.) fruit, but their role in generation of fruit flavor volatiles has been unclear. To assess the physiological role of TomloxC in the generation of volatile C6 aldehyde and alcohol flavor compounds, we produced transgenic tomato plants with greatly reduced TomloxC using sense and antisense constructs under control of the cauliflower mosaic virus 35S promoter. The expression level of the TomloxC mRNA in some transgenic plants was selectively reduced by gene silencing or antisense inhibition to between 1% and 5% of the wild-type controls, but the expression levels of mRNAs for the four other isoforms were unaffected. The specific depletion of TomloxC in transgenic tomatoes led to a marked reduction in the levels of known flavor volatiles, including hexanal, hexenal, and hexenol, to as little as 1.5% of those of wild-type controls following maceration of ripening fruit. Addition of linoleic or linolenic acid to fruit homogenates significantly increased the levels of flavor volatiles, but the increase with the TomloxC-depleted transgenic fruit extracts was much lower than with the wild-type control. Confocal imaging of tobacco (Nicotiana tabacum) leaf cells expressing a TomloxC-GFP fusion confirmed a chloroplast localization of the protein. Together, these results suggest that TomloxC is a chloroplast-targeted lipoxygenase isoform that can use both linoleic and linolenic acids as substrates to generate volatile C6 flavor compounds. The roles of the other lipoxygenase isoforms are discussed. 相似文献