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1.
Front Genet ; 12: 674783, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34306019

RESUMO

Amaryllidaceae is a large family with more than 1,600 species, belonging to 75 genera. The largest genus-Allium-is vast, comprising about a thousand species. Allium species (as well as other members of the Amaryllidaceae) are widespread and diversified, they are adapted to a wide range of habitats from shady forests to open habitats like meadows, steppes, and deserts. The genes present in chloroplast genomes (plastomes) play fundamental roles for the photosynthetic plants. Plastome traits could thus be associated with geophysical abiotic characteristics of habitats. Most chloroplast genes are highly conserved and are used as phylogenetic markers for many families of vascular plants. Nevertheless, some studies revealed signatures of positive selection in chloroplast genes of many plant families including Amaryllidaceae. We have sequenced plastomes of the following nine Allium (tribe Allieae of Allioideae) species: A. zebdanense, A. moly, A. victorialis, A. macleanii, A. nutans, A. obliquum, A. schoenoprasum, A. pskemense, A. platyspathum, A. fistulosum, A. semenovii, and Nothoscordum bivalve (tribe Leucocoryneae of Allioideae). We compared our data with previously published plastomes and provided our interpretation of Allium plastome genes' annotations because we found some noteworthy inconsistencies with annotations previously reported. For Allium species we estimated the integral evolutionary rate, counted SNPs and indels per nucleotide position as well as compared pseudogenization events in species of three main phylogenetic lines of genus Allium to estimate whether they are potentially important for plant physiology or just follow the phylogenetic pattern. During examination of the 38 species of Allium and the 11 of other Amaryllidaceae species we found that rps16, rps2, infA, ccsA genes have lost their functionality multiple times in different species (regularly evolutionary events), while the pseudogenization of other genes was stochastic events. We found that the "normal" or "pseudo" state of rps16, rps2, infA, ccsA genes correlates well with the evolutionary line of genus the species belongs to. The positive selection in various NADH dehydrogenase (ndh) genes as well as in matK, accD, and some others were found. Taking into account known mechanisms of coping with excessive light by cyclic electron transport, we can hypothesize that adaptive evolution in genes, coding subunits of NADH-plastoquinone oxidoreductase could be driven by abiotic factors of alpine habitats, especially by intensive light and UV radiation.

2.
Proc Natl Acad Sci U S A ; 117(49): 31249-31258, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229550

RESUMO

For species to stay temporally tuned to their environment, they use cues such as the accumulation of degree-days. The relationships between the timing of a phenological event in a population and its environmental cue can be described by a population-level reaction norm. Variation in reaction norms along environmental gradients may either intensify the environmental effects on timing (cogradient variation) or attenuate the effects (countergradient variation). To resolve spatial and seasonal variation in species' response, we use a unique dataset of 91 taxa and 178 phenological events observed across a network of 472 monitoring sites, spread across the nations of the former Soviet Union. We show that compared to local rates of advancement of phenological events with the advancement of temperature-related cues (i.e., variation within site over years), spatial variation in reaction norms tend to accentuate responses in spring (cogradient variation) and attenuate them in autumn (countergradient variation). As a result, among-population variation in the timing of events is greater in spring and less in autumn than if all populations followed the same reaction norm regardless of location. Despite such signs of local adaptation, overall phenotypic plasticity was not sufficient for phenological events to keep exact pace with their cues-the earlier the year, the more did the timing of the phenological event lag behind the timing of the cue. Overall, these patterns suggest that differences in the spatial versus temporal reaction norms will affect species' response to climate change in opposite ways in spring and autumn.


Assuntos
Adaptação Fisiológica/fisiologia , Mudança Climática , Monitoramento Ambiental , População , Animais , Ecossistema , Estações do Ano , Temperatura , U.R.S.S.
4.
Sci Data ; 7(1): 47, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047153

RESUMO

We present an extensive, large-scale, long-term and multitaxon database on phenological and climatic variation, involving 506,186 observation dates acquired in 471 localities in Russian Federation, Ukraine, Uzbekistan, Belarus and Kyrgyzstan. The data cover the period 1890-2018, with 96% of the data being from 1960 onwards. The database is rich in plants, birds and climatic events, but also includes insects, amphibians, reptiles and fungi. The database includes multiple events per species, such as the onset days of leaf unfolding and leaf fall for plants, and the days for first spring and last autumn occurrences for birds. The data were acquired using standardized methods by permanent staff of national parks and nature reserves (87% of the data) and members of a phenological observation network (13% of the data). The database is valuable for exploring how species respond in their phenology to climate change. Large-scale analyses of spatial variation in phenological response can help to better predict the consequences of species and community responses to climate change.


Assuntos
Biota , Mudança Climática , Bases de Dados Factuais , Quirguistão , República de Belarus , Federação Russa , Estações do Ano , Ucrânia , Uzbequistão
5.
PhytoKeys ; (90): 89-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29391852

RESUMO

Dryopteris blanfordii (C.Hope) C.Chr. is a member of the Dryopteridaceae, growing in high altitude Picea or Abies forests (2900-3500 m) in China and India. Phylogenetic relationships between D. blanfordii subsp. nigrosquamosa and closely related species of Dryopteris were investigated using a combined analysis of multiple molecular data sets (the protein-coding region of rbcL and matK genes and intergenic spacers psbA-trnH, trnP-petG, rps4-trnS, trnL-trnF and rbcL-accD). An assumption about the position of D. blanfordii subsp. nigrosquamosa within Dryopteris was made by using the Maximum Likelihood and Bayesian Inference approach and chloroplast marker sequences of Dryopteris species from GenBank. The results demonstrated that Asian taxa D. blanfordii subsp. nigrosquamosa and D. laeta as well as two American species D. arguta and D. marginalis belong to the same clade, all four of them being part of Dryopteris section Dryopteris.

6.
Rejuvenation Res ; 13(4): 453-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20681748

RESUMO

This study investigated the effect of antioxidants, i.e., carnosine and its Trolox- (water-soluble analog of alpha-tocopherol) acylated derivatives (S,S)-6-hydroxy-2,5,7,8-tetramethylchroman-2-carbonyl-beta-alanyl-L-histidine (S,S-Trolox-carnosine, STC) and (R,S)-6-hydroxy-2,5,7,8-tetramethylchroman-2-carbonyl-beta-alanyl-L-histidine (R,S-Trolox-carnosine, RTC) on the life span of the fruit fly Drosophila melanogaster. Adding carnosine to foodstuff was accompanied and followed by a 20% increase in the average life span of males, but it did not influence the average life span of females. At the same time, adding STC to foodstuff prolonged average longevity both in males (by 16%) and females (by 36%), but the addition of RTC to foodstuff had no influence upon the average life span of insects of either gender. The compounds studied have previously been shown to protect neurons of the rat brain from oxidative stress in the descending order of efficiency: RTC > STC > carnosine. The finding obtained in the present study suggests another order of efficacy regarding the effect on life span in male insects: STC > carnosine > RTC (inefficient). No correlation between antioxidant protection of rat neurons and the effect on life span of the fruit fly makes it possible to suppose the presence of additional cellular targets to be acted upon by exposure of D. melanogaster to these compounds.


Assuntos
Carnosina/farmacologia , Cromanos/química , Drosophila melanogaster/fisiologia , Longevidade/efeitos dos fármacos , Animais , Carnosina/química , Feminino , Masculino
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