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11.
Filoviruses require endosomal cysteine proteases for entry but exhibit distinct protease preferences
Misasi J Chandran K Yang JY Considine B Filone CM Côté M Sullivan N Fabozzi G Hensley L Cunningham J 《Journal of virology》2012,86(6):3284-3292
Filoviruses are enveloped viruses that cause sporadic outbreaks of severe hemorrhagic fever [CDC, MMWR Morb. Mortal. Wkly. Rep. 50:73-77, 2001; Colebunders and Borchert, J. Infect. 40:16-20, 2000; Colebunders et al., J. Infect. Dis. 196(Suppl. 2):S148-S153, 2007; Geisbert and Jahrling, Nat. Med. 10:S110-S121, 2004]. Previous studies revealed that endosomal cysteine proteases are host factors for ebolavirus Zaire (Chandran et al., Science 308:1643-1645, 2005; Schornberg et al., J. Virol. 80:4174-4178, 2006). In this report, we show that infection mediated by glycoproteins from other phylogenetically diverse filoviruses are also dependent on these proteases and provide additional evidence indicating that they cleave GP1 and expose the binding domain for the critical host factor Niemann-Pick C1. Using selective inhibitors and knockout-derived cell lines, we show that the ebolaviruses Zaire and Cote d'Ivoire are strongly dependent on cathepsin B, while the ebolaviruses Sudan and Reston and Marburg virus are not. Taking advantage of previous studies of cathepsin B inhibitor-resistant viruses (Wong et al., J. Virol. 84:163-175, 2010), we found that virus-specific differences in the requirement for cathepsin B are correlated with sequence polymorphisms at residues 47 in GP1 and 584 in GP2. We applied these findings to the analysis of additional ebolavirus isolates and correctly predicted that the newly identified ebolavirus species Bundibugyo, containing D47 and I584, is cathepsin B dependent and that ebolavirus Zaire-1995, the single known isolate of ebolavirus Zaire that lacks D47, is not. We also obtained evidence for virus-specific differences in the role of cathepsin L, including cooperation with cathepsin B. These studies strongly suggest that the use of endosomal cysteine proteases as host factors for entry is a general property of members of the family Filoviridae. 相似文献
12.
Kaur Jaspreet Kumar Vikas Sharma Kartik Kaur Sawinder Gat Yogesh Goyal Ankit Tanwar Beenu 《International journal of peptide research and therapeutics》2020,26(1):33-41
International Journal of Peptide Research and Therapeutics - Bioactive peptides have been reported to exhibit opioid-like activity and are termed as opioid peptides. Either these are produced... 相似文献
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Eben Goodale Hari Sridhar Kathryn E. Sieving Priti Bangal Gabriel J. Colorado Z. Damien R. Farine Eckhard W. Heymann Harrison H. Jones Indrikis Krams Ari E. Martínez Flavia Montao‐Centellas Jenny Muoz Umesh Srinivasan Anne Theo Kartik Shanker 《Biological reviews of the Cambridge Philosophical Society》2020,95(4):889-910
Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single‐species groups wherein all individuals obtain the same supplementary, group‐size‐related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader–follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities. 相似文献
14.
Baruah Indrani Baruah Geetanjali Sahu Jagajjit Singha Dhanawantari L. Dekaboruah Hariprasanna Velmurugan Natarajan Chikkaputtaiah Channakeshavaiah 《Plant Molecular Biology Reporter》2021,39(2):471-471
Plant Molecular Biology Reporter - The affiliation 2 in the published article was Academy of Scientific and Innovative Research (AcSIR), CSIR-NEIST Campus, Jorhat, Assam 785,006, India. 相似文献
15.
David C. Kombo Terry A. Hauser Vladimir P. Grinevich Matthew S. Melvin Jon-Paul Strachan Serguei S. Sidach Joseph Chewning Nikolai Fedorov Kartik Tallapragada Scott R. Breining Craig H. Miller 《Bioorganic & medicinal chemistry letters》2013,23(5):1450-1455
We have carried out a pharmacological evaluation of arylmethylene quinuclidine derivatives interactions with human α3β4 nAChRs subtype, using cell-based receptor binding, calcium-influx, electrophysiological patch-clamp assays and molecular modeling techniques. We have found that the compounds bind competitively to the α3β4 receptor with micromolar affinities and some of the compounds behave as non-competitive antagonists (compounds 1, 2 and 3), displaying submicromolar IC50 values. These evidences suggest a mixed mode of action for these compounds, having interactions at the orthosteric site and more pronounced interactions at an allosteric site to block agonist effects. One of the compounds, 1-benzyl-3-(diphenylmethylene)-1-azoniabicyclo[2.2.2]octane chloride (compound 3), exhibited poorly reversible use-dependent block of α3β4 channels. We also found that removal of a phenyl group from compound 1 confers a partial agonism to the derived analog (compound 6). Introducing a hydrogen-bond acceptor into the 3-benzylidene quinuclidine derivative (compound 7) increases agonism potency at the α3β4 receptor subtype. Docking into the orthosteric binding site of a α3β4 protein structure derived by comparative modeling accurately predicted the experimentally-observed trend in binding affinity. Results supported the notion that binding requires a hydrogen bond formation between the ligand basic nitrogen and the backbone carbonyl oxygen atom of the conserved Trp-149. 相似文献
16.
Kartik S. Bane Simone Lepper Jessica Kehrer Julia M. Sattler Mirko Singer Miriam Reinig Dennis Klug Kirsten Heiss Jake Baum Ann-Kristin Mueller Friedrich Frischknecht 《PLoS pathogens》2016,12(7)
Parasites causing malaria need to migrate in order to penetrate tissue barriers and enter host cells. Here we show that the actin filament-binding protein coronin regulates gliding motility in Plasmodium berghei sporozoites, the highly motile forms of a rodent malaria-causing parasite transmitted by mosquitoes. Parasites lacking coronin show motility defects that impair colonization of the mosquito salivary glands but not migration in the skin, yet result in decreased transmission efficiency. In non-motile sporozoites low calcium concentrations mediate actin-independent coronin localization to the periphery. Engagement of extracellular ligands triggers an intracellular calcium release followed by the actin-dependent relocalization of coronin to the rear and initiation of motility. Mutational analysis and imaging suggest that coronin organizes actin filaments for productive motility. Using coronin-mCherry as a marker for the presence of actin filaments we found that protein kinase A contributes to actin filament disassembly. We finally speculate that calcium and cAMP-mediated signaling regulate a switch from rapid parasite motility to host cell invasion by differentially influencing actin dynamics. 相似文献
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Prantik Sharma Baruah Kishor Deka Lipika Lahkar Bhaskar Sarma S.K. Borthakur Bhaben Tanti 《农业工程》2019,39(1):42-49
Elaeocarpus serratus L., commonly known as ‘rudraksh’ referred in the Ayurveda as a wonderful plant for strengthening body constitutions, has been recognized as a threatened plant of Assam, India. Traditionally, rudraksh beads, its bark and leaves are used to cure various ailments like stress, anxiety, depression, nerve pain, epilepsy, migraine, lack of concentration, asthma, hypertension, arthritis and liver diseases. The population stock of the species has been depleting very fast in its natural habitat due to rapid habitat fragmentation and changing climate altering the structural and functional integrity of the plant. Hence, conservation of E. serratus L. with proper scientific investigation to prevent from extinction in its wild habitat is urgently needed. The present study was emphasized with the specific objectives to study the distribution and population status, predication of suitable sites through ENM, standardization of macropropagation methods and reinforcement/reintroduction into the suitable wild habitat to improve conservation status. In the present investigation E. serratus L. was reported in few locations of Assam and Arunachal Pradesh with population sizes of mean density, frequency of occurrence and abundance in relation to other associated species as 0.333, 13.922 and 2.215 respectively. For improving the conservation status, potential area and habitat for reinforcement was predicted using Maximum Entropy (MaxEnt) distribution modelling algorithm. Subsequently, macropropagation protocol was standardized through seed germination and air-layering; saplings were raised and 1050 saplings were reintroduced to the wild habitats selected on the basis of ecological niche modelling. Survival rate was found significantly high as 68%, suggesting that our approach is effective for changing population status and to conserve the plant. 相似文献
20.
Ferdinand Bohlmann Christa Zdero Jasmin Jakupovic Laxmi N. Misra Shanta Banerjee Pahup Singh Robindra N. Baruah Mohamed A. Metwally Guillermo Schmeda-Hirschmann Leszek P.D. Vincent Robert M. King Harold Robinson 《Phytochemistry》1985,24(6):1249-1261
The investigation and reinvestigation respectively of 23 Senecio species afforded 11 further cacalol derivatives, a furoeremophilone, 17 eremophilanes, 4 bisabolene derivatives, a shikimic acid derivative, a bis-prenylated p-hydroxybenzaldehyde, menth-2-en- 1,7-diol and a cumol derivative. The configuration of some eremophilanes have been revised. Structures were elucidated by spectroscopic methods. The results are summarized in a table. The chemotaxonomic aspects agree with those of previous investigations. 相似文献