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921.
Dong-chuan Guo Ellen S. Regalado Amelie Pinard Jiyuan Chen Kwanghyuk Lee Christina Rigelsky Lior Zilberberg Ellen M. Hostetler Micheala Aldred Stephanie E. Wallace Siddharth K. Prakash Suzanne M. Leal Michael J. Bamshad Deborah A. Nickerson Marvin Natowicz Daniel B. Rifkin Dianna M. Milewicz 《American journal of human genetics》2018,102(4):706-712
922.
923.
Suppression of oxidative phosphorylation confers resistance against bevacizumab in experimental glioma
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![点击此处可从《Journal of neurochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jule A. Eriksson Christina Wanka Michael C. Burger Hans Urban Ines Hartel Janusz von Renesse Patrick N. Harter Michel Mittelbronn Joachim P. Steinbach Johannes Rieger 《Journal of neurochemistry》2018,144(4):421-430
924.
Nimodipine confers clinical improvement in two models of experimental autoimmune encephalomyelitis
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![点击此处可从《Journal of neurochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jens Ingwersen Lorenzo De Santi Britta Wingerath Jonas Graf Barbara Koop Reiner Schneider Christina Hecker Friederike Schröter Mary Bayer Anna Dorothee Engelke Michael Dietrich Philipp Albrecht Hans‐Peter Hartung Pasquale Annunziata Orhan Aktas Tim Prozorovski 《Journal of neurochemistry》2018,146(1):86-98
925.
Non‐breeding range size predicts the magnitude of population trends in trans‐Saharan migratory passerine birds
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![点击此处可从《Oikos》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jaroslav Koleček Petr Procházka Christina Ieronymidou Ian J. Burfield Jiří Reif 《Oikos》2018,127(4):599-606
Understanding why populations of some migratory species show a directional change over time, i.e. increase or decrease, while others do not, remains a challenge for ecological research. One possible explanation is that species with smaller non‐breeding ranges may have more pronounced directional population trends, and their populations are thus more sensitive to the variation in environmental conditions in their non‐breeding quarters. According to the serial residency hypothesis, this sensitivity should lead to higher magnitudes (i.e. absolute values) of population trends for species with smaller non‐breeding ranges, with the direction of trend being either positive or negative depending on the nature of the environmental change. We tested this hypothesis using population trends over 2001–2012 for 36 sub‐Saharan migratory passerine birds breeding in Europe. Namely, we related the magnitude of the species' population trends to the size of their sub‐Saharan non‐breeding grounds, whilst controlling for factors including number of migration routes, non‐breeding habitat niche and wetness, breeding habitat type and life‐history strategy. The magnitude of species' population trends grew with decreasing absolute size of sub‐Saharan non‐breeding ranges, and this result remained significant when non‐breeding range size was expressed relative to the size of the breeding range. After repeating the analysis with the trend direction, the relationship with the non‐breeding range size disappeared, indicating that both population decreases and increases are frequent amongst species with small non‐breeding range sizes. Therefore, species with small non‐breeding ranges are at a higher risk of population decline due to adverse factors such as habitat loss or climatic extremes, but their populations are also more likely to increase when suitable conditions appear. As non‐breeding ranges may originate from stochasticity of non‐breeding site selection in naive birds (‘serial‐residency’ hypothesis), it is crucial to maintain a network of stable and resilient habitats over large areas of birds’ non‐breeding quarters. 相似文献
926.
Structure of a putative ClpS N‐end rule adaptor protein from the malaria pathogen Plasmodium falciparum
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Christina L. Vizcarra Duilio Cascio Pascal F. Egea 《Protein science : a publication of the Protein Society》2016,25(3):689-701
The N‐end rule pathway uses an evolutionarily conserved mechanism in bacteria and eukaryotes that marks proteins for degradation by ATP‐dependent chaperones and proteases such as the Clp chaperones and proteases. Specific N‐terminal amino acids (N‐degrons) are sufficient to target substrates for degradation. In bacteria, the ClpS adaptor binds and delivers N‐end rule substrates for their degradation upon association with the ClpA/P chaperone/protease. Here, we report the first crystal structure, solved at 2.7 Å resolution, of a eukaryotic homolog of bacterial ClpS from the malaria apicomplexan parasite Plasmodium falciparum (Pfal). Despite limited sequence identity, Plasmodium ClpS is very similar to bacterial ClpS. Akin to its bacterial orthologs, plasmodial ClpS harbors a preformed hydrophobic pocket whose geometry and chemical properties are compatible with the binding of N‐degrons. However, while the N‐degron binding pocket in bacterial ClpS structures is open and accessible, the corresponding pocket in Plasmodium ClpS is occluded by a conserved surface loop that acts as a latch. Despite the closed conformation observed in the crystal, we show that, in solution, Pfal‐ClpS binds and discriminates peptides mimicking bona fide N‐end rule substrates. The presence of an apicoplast targeting peptide suggests that Pfal‐ClpS localizes to this plastid‐like organelle characteristic of all Apicomplexa and hosting most of its Clp machinery. By analogy with the related ClpS1 from plant chloroplasts and cyanobacteria, Plasmodium ClpS likely functions in association with ClpC in the apicoplast. Our findings open new venues for the design of novel anti‐malarial drugs aimed at disrupting parasite‐specific protein quality control pathways. 相似文献
927.
Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis)
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![点击此处可从《Molecular ecology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
W. Chris Funk Robert E. Lovich Paul A. Hohenlohe Courtney A. Hofman Scott A. Morrison T. Scott Sillett Cameron K. Ghalambor Jesus E. Maldonado Torben C. Rick Mitch D. Day Nicholas R. Polato Sarah W. Fitzpatrick Timothy J. Coonan Kevin R. Crooks Adam Dillon David K. Garcelon Julie L. King Christina L. Boser Nicholas Gould William F. Andelt 《Molecular ecology》2016,25(10):2176-2194
The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction‐site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome‐wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential. 相似文献
928.
929.
Infanticide and within‐clutch competition select for reproductive synchrony in a cooperative bird
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Christina Riehl 《Evolution; international journal of organic evolution》2016,70(8):1760-1769
Reproduction among members of social animal groups is often highly synchronized, but neither the selective advantages nor the proximate causes of synchrony are fully understood. Here I investigate the evolution of hatching synchrony in the Greater Ani (Crotophaga major), a communally nesting bird in which several unrelated females contribute eggs to a large, shared clutch. Hatching synchrony is variable, ranging from complete synchrony to moderate asynchrony, and is determined by the onset of incubation of the communal clutch. Data from a 10‐year field study indicate that individual reproductive success is highest in synchronous groups, and that nestlings that hatch in the middle of the hatching sequence are most likely to survive. Nestling mortality is high in asynchronous clutches because early‐hatching nestlings are more likely to be killed by adult group members, whereas late‐hatching nestlings are more likely to starve due competition with their older nest‐mates. Therefore, the timing of hatching appears to be under stabilizing selection from infanticide and resource competition acting in concert. These results provide empirical support for models predicting that synchrony may evolve as an adaptive counter‐strategy to infanticide, and they highlight the importance of competition in shaping the timing of reproduction in social groups. 相似文献