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Sam Kaitaniemi Heli Elovaara Kirsi Grön Heidi Kidron Janne Liukkonen Tiina Salminen Marko Salmi Sirpa Jalkanen Kati Elima 《Cellular and molecular life sciences : CMLS》2009,66(16):2743-2757
Semicarbazide-sensitive amine oxidases (SSAOs) catalyze oxidative deamination of primary amines, but the true physiological
function of these enzymes is still poorly understood. Here, we have studied the functional and structural characteristics
of a human cell-surface SSAO, AOC2, which is homologous to the better characterized family member, AOC3. The preferred in
vitro substrates of AOC2 were found to be 2-phenylethylamine, tryptamine and p-tyramine instead of methylamine and benzylamine, the favored substrates of AOC3. Molecular modeling suggested structural
differences between AOC2 and AOC3, which provide AOC2 with the capability to use the larger monoamines as substrates. Even
though AOC2 mRNA was expressed in many tissues, the only tissues with detectable AOC2-like enzyme activity were found in the
eye. Characterization of AOC2 will help in evaluating the contribution of this enzyme to the pathological processes attributed
to the SSAO activity and in designing specific inhibitors for the individual members of the SSAO family.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Malaria is a major cause of morbidity and mortality in the developing world and cerebral malaria is responsible for the majority
of malaria-associated deaths. There is a strong association between thrombocytopenia and outcome in malaria, suggesting a
role for platelets in the pathogenesis of malaria. This thrombocytopenia is likely due to platelet activation possibly through
an interaction between PfEMP1 on plasmodium and CD36 on platelets. Platelet activation by plasmodium has two potential consequences.
It can lead to the formation of micro-aggregates of infected red blood cells and platelets which can occlude blood vessels
and it also leads to binding to and activation of the endothelium. 相似文献
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Shuzhi Sam GE Beibei REN Tong Heng LEE 《系统科学与复杂性》2007,20(2):215-224
In this paper, control design is investigated for hard disk drives in mobile applications with unknown external arbitrarily fast time-varying disturbances. The disturbances can be estimated with exponential accuracy using the proposed disturbance observer based on a series of integral filters. The position error signal will converge to zero with the proposed control technique for systems subjected to the unknown disturbances. The effectiveness of the proposed method is demonstrated by extensive simulation studies. 相似文献
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Galagan JE Calvo SE Cuomo C Ma LJ Wortman JR Batzoglou S Lee SI Baştürkmen M Spevak CC Clutterbuck J Kapitonov V Jurka J Scazzocchio C Farman M Butler J Purcell S Harris S Braus GH Draht O Busch S D'Enfert C Bouchier C Goldman GH Bell-Pedersen D Griffiths-Jones S Doonan JH Yu J Vienken K Pain A Freitag M Selker EU Archer DB Peñalva MA Oakley BR Momany M Tanaka T Kumagai T Asai K Machida M Nierman WC Denning DW Caddick M Hynes M Paoletti M Fischer R Miller B Dyer P Sachs MS Osmani SA Birren BW 《Nature》2005,438(7071):1105-1115
The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation. 相似文献
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Systemic Practice and Action Research - Community indicators have been of special interest to scholars worldwide, because of their vital role in community development. Nevertheless, the best way to... 相似文献
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Exogenous double-stranded RNA (dsRNA) has been shown to exert homology-dependent effects at the level of both target mRNA stability and chromatin structure. Using C. elegans undergoing RNAi as an animal model, we have investigated the generality, scope and longevity of dsRNA-targeted chromatin effects and their dependence on components of the RNAi machinery. Using high-resolution genome-wide chromatin profiling, we found that a diverse set of genes can be induced to acquire locus-specific enrichment of histone H3 lysine 9 trimethylation (H3K9me3), with modification footprints extending several kilobases from the site of dsRNA homology and with locus specificity sufficient to distinguish the targeted locus from the other 20,000 genes in the C. elegans genome. Genetic analysis of the response indicated that factors responsible for secondary siRNA production during RNAi were required for effective targeting of chromatin. Temporal analysis revealed that H3K9me3, once triggered by dsRNA, can be maintained in the absence of dsRNA for at least two generations before being lost. These results implicate dsRNA-triggered chromatin modification in C. elegans as a programmable and locus-specific response defining a metastable state that can persist through generational boundaries. 相似文献
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McLellan JS Pancera M Carrico C Gorman J Julien JP Khayat R Louder R Pejchal R Sastry M Dai K O'Dell S Patel N Shahzad-ul-Hussan S Yang Y Zhang B Zhou T Zhu J Boyington JC Chuang GY Diwanji D Georgiev I Kwon YD Lee D Louder MK Moquin S Schmidt SD Yang ZY Bonsignori M Crump JA Kapiga SH Sam NE Haynes BF Burton DR Koff WC Walker LM Phogat S Wyatt R Orwenyo J Wang LX Arthos J Bewley CA Mascola JR Nabel GJ Schief WR Ward AB Wilson IA Kwong PD 《Nature》2011,480(7377):336-343
Variable regions 1 and 2 (V1/V2) of human immunodeficiency virus-1 (HIV-1) gp120 envelope glycoprotein are critical for viral evasion of antibody neutralization, and are themselves protected by extraordinary sequence diversity and N-linked glycosylation. Human antibodies such as PG9 nonetheless engage V1/V2 and neutralize 80% of HIV-1 isolates. Here we report the structure of V1/V2 in complex with PG9. V1/V2 forms a four-stranded β-sheet domain, in which sequence diversity and glycosylation are largely segregated to strand-connecting loops. PG9 recognition involves electrostatic, sequence-independent and glycan interactions: the latter account for over half the interactive surface but are of sufficiently weak affinity to avoid autoreactivity. The structures of V1/V2-directed antibodies CH04 and PGT145 indicate that they share a common mode of glycan penetration by extended anionic loops. In addition to structurally defining V1/V2, the results thus identify a paradigm of antibody recognition for highly glycosylated antigens, which-with PG9-involves a site of vulnerability comprising just two glycans and a strand. 相似文献
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Gizzard shad ( Dorosoma cepedianum ) were introduced into the Colorado River Basin circa 1996 via an unintentional contaminated stocking. Gizzard shad were collected throughout much of the Upper Colorado River Basin in 2005, 2006, and 2007. These collections document a rapid range expansion of this introduced species and a threat to intact fisheries. 相似文献