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41.
N‐glycan maturation mutants in Lotus japonicus for basic and applied glycoprotein research 下载免费PDF全文
Carina T. Pedersen Ian Loke Andrea Lorentzen Sara Wolf Manoj Kamble Sebastian K. Kristensen David Munch Simona Radutoiu Edzard Spillner Peter Roepstorff Morten Thaysen‐Andersen Jens Stougaard Svend Dam 《The Plant journal : for cell and molecular biology》2017,91(3):394-407
Studies of protein N‐glycosylation are important for answering fundamental questions on the diverse functions of glycoproteins in plant growth and development. Here we generated and characterised a comprehensive collection of Lotus japonicusLORE1 insertion mutants, each lacking the activity of one of the 12 enzymes required for normal N‐glycan maturation in the glycosylation machinery. The inactivation of the individual genes resulted in altered N‐glycan patterns as documented using mass spectrometry and glycan‐recognising antibodies, indicating successful identification of null mutations in the target glyco‐genes. For example, both mass spectrometry and immunoblotting experiments suggest that proteins derived from the α1,3‐fucosyltransferase (Lj3fuct) mutant completely lacked α1,3‐core fucosylation. Mass spectrometry also suggested that the Lotus japonicus convicilin 2 was one of the main glycoproteins undergoing differential expression/N‐glycosylation in the mutants. Demonstrating the functional importance of glycosylation, reduced growth and seed production phenotypes were observed for the mutant plants lacking functional mannosidase I, N‐acetylglucosaminyltransferase I, and α1,3‐fucosyltransferase, even though the relative protein composition and abundance appeared unaffected. The strength of our N‐glycosylation mutant platform is the broad spectrum of resulting glycoprotein profiles and altered physiological phenotypes that can be produced from single, double, triple and quadruple mutants. This platform will serve as a valuable tool for elucidating the functional role of protein N‐glycosylation in plants. Furthermore, this technology can be used to generate stable plant mutant lines for biopharmaceutical production of glycoproteins displaying relative homogeneous and mammalian‐like N‐glycosylation features. 相似文献
42.
TomExpress,a unified tomato RNA‐Seq platform for visualization of expression data,clustering and correlation networks 下载免费PDF全文
43.
Mikael Calner 《Facies》2005,51(1-4):584-591
Recent and ancient carbonate platforms are major marine ecosystems, built by various carbonate-secreting organisms with different sensitivity for environmental change. For this reason, carbonate platforms are excellent sensors for changes in contemporaneous marine environments. A variety of ecosystem changes in carbonate platforms have previously been recognised in the aftermath of mass extinction events. This paper addresses how two Silurian extinction events among graptolites, conodonts, and pentamerid brachiopods can be related to changes in the style of carbonate production and general evolution of low latitude carbonate platforms in a similar way as previously reported from the major five mass extinctions of the Phanerozoic. Strata formed on Gotland during the Mulde and Lau events share remarkably many similarities but are strikingly different in composition compared to other strata on the island. The event-related strata is characterised by the sudden appearance of widespread oolites, deviating reef composition, flat-pebble conglomerates, abundant micro- and macro-oncoids, stromatolites, and other microbial facies suggesting decreased bioturbation levels in contemporaneous shelf seas. Importantly, these changes can be tied to high-resolution biostratigraphic frameworks and global stable isotope excursions. The anomalous intervals may therefore be searched for elsewhere in order to test their regional or global significance. 相似文献
44.
Luca Basilone 《Facies》2009,55(1):115-135
The Rocca Busambra ridge in western Sicily is a shallow to pelagic Meso-Cenozoic carbonate structural unit of the Sicilian
Chain with a variety of tectono-sedimentary features. Palaeofaults, unconformities (buttress unconformity, onlap, downlap),
a network of neptunian dykes with several infilling generations, several large hiatuses, different facies and lateral facies
changes, and erosional submarine and subaerial surfaces are observed. Detailed fieldwork and structural analyses have indicated
the occurrence of fault planes with different orientations. These data, combined with facies studies and physical-stratigraphy
analyses, allow for the distinction of different depositional regions. A lateral change from an open-marine carbonate platform
with a stepped fault margin (located in the westernmost sector) to a deeper basinal depositional setting in the east, in the
context of an upper slope scalloped margin and base-of-slope systems with talus breccias, is envisaged here. Extensional to
transtensional tectonic pulses punctuated the sedimentary evolution during Early Toarcian, Late Jurassic, Early Cretaceous,
Late Cretaceous, and Early Miocene times. The collected data show that most fault planes have preserved their original orientations
throughout the reactivation processes. The reconstructed Meso-Cenozoic tectono-sedimentary evolution is closely related to
the late syn-rift and post-rift tectonic evolution of the Tethyan continental margin. 相似文献
45.
Yang Zhang 《生物化学与生物物理学报:生物膜》2009,1788(1):178-149
Membrane lipids seem to be organized and not randomly distributed in the cell membrane. In particular, sphingolipids seem to interact with cholesterol in the outer leaflet of the cell membrane resulting in the formation of distinct membrane domains, i.e. rafts. The generation of ceramide within rafts alters their biophysical properties and results in the formation of large ceramide-enriched membrane platforms. These platforms serve to cluster receptor molecules and to organize intracellular signalling molecules to facilitate signal transduction via a receptor upon stimulation. Thus, ceramide-enriched membrane domains amplify not only receptor-, but also stress-mediated signalling events. Although many receptors cluster, the molecular mechanisms mediating this important and general event in signal transduction need to be identified. 相似文献
46.
Guangyong Zheng ;Hong Li ;Chuan Wang ;Quanhu Sheng ;Haiwei Fan ;Shaoyou Yang ;Boshu Liu ;Jianliang Dai ;Rong Zeng ;Lu Xie 《Acta biochimica et biophysica Sinica》2009,(4):273-279
With the development of functional genomics research, large-scale proteomics studies are now widespread, presenting significant challenges for data storage, exchange, and analysis. Here we present the Integrated Proteomics Exploring Database (IPED) as a platform for managing proteomics experimental data (both process and result data). IPED is based on the schema of the Proteome Experimental Data Repository (PEDRo), and complies with the General Proteomics Standard (GPS) drafted by the Proteomics Standards Committee of the Human Proteome Organization. In our work, we developed three components for the IPED platform: the IPED client editor, IPED server software, and IPED web interface. The client editor collects experimental data and generates an extensible markup language (XML) data file compliant with PEDRo and GPS; the server software parses the XML data file and loads information into a core database; and the web interface displays experimental results, to provide a convenient graphic representation of data. Given software convenience and data abundance, IPED is a powerful platform for data exchange and presents an important resource for the proteomics community. In its current release, IPED is available at http://www. biosino.org/iped2. 相似文献
47.
Yu Gao Jingjing Xie Haijun Chen Songen Gu Rongli Zhao Jingwei Shao Lee Jia 《Biotechnology advances》2014
Traditional chemotherapy used today at clinics is mainly inherited from the thinking and designs made four decades ago when the Cancer War was declared. The potency of those chemotherapy drugs on in-vitro cancer cells is clearly demonstrated at even nanomolar levels. However, due to their non-specific effects in the body on normal tissues, these drugs cause toxicity, deteriorate patient's life quality, weaken the host immunosurveillance system, and result in an irreversible damage to human's own recovery power. Owing to their unique physical and biological properties, nanotechnology-based chemotherapies seem to have an ability to specifically and safely reach tumor foci with enhanced efficacy and low toxicity. Herein, we comprehensively examine the current nanotechnology-based pharmaceutical platforms and strategies for intelligent design of new nanomedicines based on targeted drug delivery system (TDDS) for cancer metastasis treatment, analyze the pros and cons of nanomedicines versus traditional chemotherapy, and evaluate the importance that nanomaterials can bring in to significantly improve cancer metastasis treatment. 相似文献
48.
49.
The depth-related patterns in the benthic megafauna of the NE Weddell Sea shelf at the edge of the Fimbul Ice Shelf were investigated
at seven sites using towed camera platform photographs. Megafaunal density decreased with depth from 77,939 ha−1 at 245 m to 8,895 ha−1 at 510 m. While diversity was variable, with H′ ranging between 1.34 and 2.28, there were no depth related patterns. Multivariate analyses revealed two distinct assemblages;
a shallow assemblage with dense patches of suspension feeders in undisturbed areas and a deep assemblage where these were
not present. Disturbance from icebergs explained many observed patterns in faunal distribution. In shallow waters probable
effects of disturbance were observed as changes in successional stages; in deeper waters changes in habitat as a result of
past disturbance explained faunal distributions. In deeper areas ice ploughing created a mosaic landscape of fine and coarse
sediments. Total megafaunal density was highest in areas of coarse sediment (up to 2.9 higher than in finer sediment areas)
but diversity was highest in intermediate areas (H′ = 2.35). 相似文献
50.
生态环境损害鉴定评估业务化技术研究 总被引:1,自引:10,他引:1
随着社会经济的不断发展和人类需求的不断提高,我国生态环境损害事件屡有发生,由于人类活动导致的典型生态系统结构和功能退化、生态系统服务降低等生态环境损害严重威胁到我国的生态安全。系统研究典型生态系统生态环境损害基线、因果关系及损害程度的判定技术方法对保障国家生态安全和实现可持续发展具有重要的理论和实践意义。根据国家"十三五"《典型脆弱生态修复与保护研究专项指南》的要求,中国科学院大学牵头组织6家课题牵头单位联合申报了"生态环境损害鉴定评估业务化技术研究"项目,通过了专业机构组织的评审,获准立项。本文对该项目的研究背景、总体目标、主要内容及预期产出进行了介绍。该项目的开展将对典型生态环境损害评估提供决策支持,为国家在政策层面解决环境损害追责、环境执法与管理提供科学技术和平台支撑。 相似文献