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991.
Respiration in Saccharomyces cerevisiae is regulated by small proteins such as the respiratory supercomplex factors (Rcf). One of these factors (Rcf1) has been shown to interact with complexes III (cyt. bc1) and IV (cytochrome c oxidase, CytcO) of the respiratory chain and to modulate the activity of the latter. Here, we investigated the effect of deleting Rcf1 on the functionality of CytcO, purified using a protein C-tag on core subunit 1 (Cox1). Specifically, we measured the kinetics of ligand binding to the CytcO catalytic site, the O2-reduction activity and changes in light absorption spectra. We found that upon removal of Rcf1 a fraction of the CytcO is incorrectly assembled with structural changes at the catalytic site. The data indicate that Rcf1 modulates the assembly and activity of CytcO by shifting the equilibrium of structural sub-states toward the fully active, intact form. 相似文献
992.
Anthony Drecourt Joël Babdor Michael Dussiot Floriane Petit Nicolas Goudin Meriem Garfa-Traoré Florence Habarou Christine Bole-Feysot Patrick Nitschké Chris Ottolenghi Metodi D. Metodiev Valérie Serre Isabelle Desguerre Nathalie Boddaert Olivier Hermine Arnold Munnich Agnès Rötig 《American journal of human genetics》2018,102(2):266-277
993.
Pia Gruber Filipe Carvalho Marco P. C. Marques Brian O'Sullivan Fabiana Subrizi Dragana Dobrijevic John Ward Helen C. Hailes Pedro Fernandes Roland Wohlgemuth Frank Baganz Nicolas Szita 《Biotechnology and bioengineering》2018,115(3):586-596
994.
Bezerra Luis Artur Valões Angelini Ronaldo Vitule Jean Ricardo Simões Coll Marta Sánchez-Botero Jorge Iván 《Hydrobiologia》2018,817(1):475-489
Hydrobiologia - Fish and invertebrates are introduced in freshwaters around the world for commercial purposes, despite widely known impacts on food webs and biological invasions. As a proxy for... 相似文献
995.
Ubirajara Dutra Capaverde Jr Lucas Gabriel do Amaral Pereira Valéria da Cunha Tavares William E. Magnusson Fabricio Beggiato Baccaro Paulo Estefano D. Bobrowiec 《Biotropica》2018,50(4):674-683
The distribution patterns of animal species at local scales have been explained by direct influences of vegetation structure, topography, food distribution, and availability. However, these variables can also interact and operate indirectly on the distribution of species. Here, we examined the direct and indirect effects of food availability (fruits and insects), vegetation clutter, and elevation in structuring phyllostomid bat assemblages in a continuous terra firme forest in Central Amazonia. Bats were captured in 49 plots over 25‐km² of continuous forest. We captured 1138 bats belonging to 52 species with 7056 net*hours of effort. Terrain elevation was the strongest predictor of species and guild compositions, and of bat abundance. However, changes in elevation were associated with changes in vegetation clutter, and availability of fruits and insects consumed by bats, which are likely to have had direct effects on bat assemblages. Frugivorous bat composition was more influenced by availability of food‐providing plants, while gleaning‐animalivore composition was more influenced by the structural complexity of the vegetation. Although probably not causal, terrain elevation may be a reliable predictor of bat‐assemblage structure at local scales in other regions. In situations where it is not possible to collect local variables, terrain elevation can substitute other variables, such as vegetation structure, and availability of fruits and insects. 相似文献
996.
M. Ben Hassen T. V. Cao J. Bartholomé G. Orasen C. Colombi J. Rakotomalala L. Razafinimpiasa C. Bertone C. Biselli A. Volante F. Desiderio L. Jacquin G. Valè N. Ahmadi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(2):417-435
Key message
Rice breeding programs based on pedigree schemes can use a genomic model trained with data from their working collection to predict performances of progenies produced through rapid generation advancement.Abstract
So far, most potential applications of genomic prediction in plant improvement have been explored using cross validation approaches. This is the first empirical study to evaluate the accuracy of genomic prediction of the performances of progenies in a typical rice breeding program. Using a cross validation approach, we first analyzed the effects of marker selection and statistical methods on the accuracy of prediction of three different heritability traits in a reference population (RP) of 284 inbred accessions. Next, we investigated the size and the degree of relatedness with the progeny population (PP) of sub-sets of the RP that maximize the accuracy of prediction of phenotype across generations, i.e., for 97 F5–F7 lines derived from biparental crosses between 31 accessions of the RP. The extent of linkage disequilibrium was high (r 2 = 0.2 at 0.80 Mb in RP and at 1.1 Mb in PP). Consequently, average marker density above one per 22 kb did not improve the accuracy of predictions in the RP. The accuracy of progeny prediction varied greatly depending on the composition of the training set, the trait, LD and minor allele frequency. The highest accuracy achieved for each trait exceeded 0.50 and was only slightly below the accuracy achieved by cross validation in the RP. Our results thus show that relatively high accuracy (0.41–0.54) can be achieved using only a rather small share of the RP, most related to the PP, as the training set. The practical implications of these results for rice breeding programs are discussed.997.
Valérie Ducret Arnaud Gaigher Céline Simon Alexandre Roulin 《Molecular ecology》2016,25(18):4551-4563
Sexual conflict arises when selection in one sex causes the displacement of the other sex from its phenotypic optimum, leading to an inevitable tension within the genome – called intralocus sexual conflict. Although the autosomal melanocortin‐1‐receptor gene (MC1R) can generate colour variation in sexually dichromatic species, most previous studies have not considered the possibility that MC1R may be subject to sexual conflict. In the barn owl (Tyto alba), the allele MC1RWHITE is associated with whitish plumage coloration, typical of males, and the allele MC1RRUFOUS is associated with dark rufous coloration, typical of females, although each sex can express any phenotype. Because each colour variant is adapted to specific environmental conditions, the allele MC1RWHITE may be more strongly selected in males and the allele MC1RRUFOUS in females. We therefore investigated whether MC1R genotypes are in excess or deficit in male and female fledglings compared with the expected Hardy–Weinberg proportions. Our results show an overall deficit of 7.5% in the proportion of heterozygotes in males and of 12.9% in females. In males, interannual variation in assortative pairing with respect to MC1R explained the year‐specific deviations from Hardy–Weinberg proportions, whereas in females, the deficit was better explained by the interannual variation in the probability of inheriting the MC1RWHITE or MC1RRUFOUS allele. Additionally, we observed that sons inherit the MC1RRUFOUS allele from their fathers on average slightly less often than expected under the first Mendelian law. Transmission ratio distortion may be adaptive in this sexually dichromatic species if males and females are, respectively, selected to display white and rufous plumages. 相似文献
998.
Cindy Aubernon Julien Boulay Valéry Hédouin Damien Charabidzé 《Entomologia Experimentalis et Applicata》2016,160(2):101-108
Due to the ephemeral nature of carcasses they grow on, necrophagous blowfly larvae should minimize the time spent on the cadaver. This could be achieved by moving to high‐temperature areas. On that basis, we theorized that larvae placed in a heterogeneous thermal environment would move to the higher temperature that speed up their development. This study was designed to (1) test the ability of necrophagous larvae to orientate in a heterogeneous thermal environment, and (2) compare the temperatures selected by the larvae of three common blowfly species: Lucilia sericata (Meigen), Calliphora vomitoria (L.) and Calliphora vicina (Robineau‐Desvoidy). For this purpose, we designed a setup we named Thermograde. It consists of a food‐supplied linear thermal gradient that allows larvae to move, feed, and grow in close‐to‐real conditions, and to choose to stay at a given temperature. For each species and replication, 80 young third instars were placed on the thermal gradient. The location of larvae was observed after 19 h, with fifteen replications per species. The larvae of each species formed aggregations that were always located at the same temperatures, which were highly species‐specific: 33.3 ± 1.52 °C for L. sericata, 29.6 ± 1.63 °C for C. vomitoria, and 22.4 ± 1.55 °C for C. vicina. According to the literature, these value allows a fast development of the larvae, but not to reach the maximum development rate. As control experiments clearly demonstrate that larval distribution was not due to differences in food quality, we hypothesized that the local temperature selection by larvae may result from a trade‐off between development quality and duration. Indeed, temperature controls not only the development rate of the larvae, but also the quality of their growth and survival rate. Finally, results raise questions regarding the way larvae moved on the gradient and located their preferential temperature. 相似文献
999.
Spatiotemporal variation in local adaptation of a specialist insect herbivore to its long‐lived host plant 下载免费PDF全文
Aino Kalske Roosa Leimu J. F. Scheepens Pia Mutikainen 《Evolution; international journal of organic evolution》2016,70(9):2110-2122
Local adaptation of interacting species to one another indicates geographically variable reciprocal selection. This process of adaptation is central in the organization and maintenance of genetic variation across populations. Given that the strength of selection and responses to it often vary in time and space, the strength of local adaptation should in theory vary between generations and among populations. However, such spatiotemporal variation has rarely been explicitly demonstrated in nature and local adaptation is commonly considered to be relatively static. We report persistent local adaptation of the short‐lived herbivore Abrostola asclepiadis to its long‐lived host plant Vincetoxicum hirundinaria over three successive generations in two studied populations and considerable temporal variation in local adaptation in six populations supporting the geographic mosaic theory. The observed variation in local adaptation among populations was best explained by geographic distance and population isolation, suggesting that gene flow reduces local adaptation. Changes in herbivore population size did not conclusively explain temporal variation in local adaptation. Our results also imply that short‐term studies are likely to capture only a part of the existing variation in local adaptation. 相似文献
1000.
Ingrid C. A. Boucaud Pénélope A. Valère Mélissa L. N. Aguirre Smith Blandine Doligez Laure Cauchard Fanny Rybak Clémentine Vignal 《Ibis》2016,158(3):630-644
Although most bird species show monogamous pair bonds and bi‐parental care, little is known of how mated birds coordinate their activities. Whether or not partners communicate with each other to adjust their behaviour remains an open question. During incubation and the first days after hatching, one parent – generally the female – stays in the nest for extended periods, and might depend on acoustic communication to exchange information with its mate outside. The Great Tit Parus major is an interesting study system to investigate intra‐pair communication at the nest because males address songs to their mate while she is in the nest cavity, and females answer the male from the cavity with calls. However, the function of this communication remains unknown. In this study, we recorded the vocalizations and observed the resulting behaviour of Great Tit pairs around the nest at different breeding stages (laying, incubation and chick‐rearing). We observed vocal exchanges (vocalization bouts, alternated on the same tempo, between the female inside the nest and her male outside) in three contexts with different outcomes: (1) the female left the nest, (2) the male entered the box with food, and the female then used specific call types, (3) mates stopped calling but did not leave or enter the nest. The structure of vocal exchanges was globally stable between contexts, but females used calls with an up‐shifted spectrum during exchanges, at the end of which they left the nest or the male entered the nest. Birds vocalized more and at higher tempo during exchanges that ended up in feeding inside the nest. Birds also vocalized more during exchanges taking place during laying – a period of active mate guarding – than during incubation. We conclude that vocal exchanges could signal the females’ need for food and the males’ mate guarding behaviour, and discuss other possible functions of this communication. 相似文献