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91.
Pável F. Matos-Maraví Carlos Peña Keith R. Willmott André V.L. Freitas Niklas Wahlberg 《Molecular phylogenetics and evolution》2013,66(1):54-68
The so-called “Taygetis clade” is a group of exclusively Neotropical butterflies classified within Euptychiina, one of the largest subtribes in the subfamily Satyrinae. Since the distribution of the ten genera belonging to this group ranges throughout the entire Neotropics, from lowlands to lower montane habitats, it offers a remarkable opportunity to study the region’s biogeographic history as well as different scenarios for speciation in upland areas. We inferred a robust and well-sampled phylogeny using DNA sequences from four genes (4035 bp in total) using maximum parsimony and Bayesian inference. We estimated divergence times using the Bayesian relaxed clock method calibrated with node ages from previous studies. Ancestral ranges of distribution were estimated using the dispersal–extinction–cladogenesis (DEC) model as implemented in the program Lagrange. We propose several taxonomic changes and recognize nine well-supported natural genera within the “Taygetis clade”: Forsterinaria (subsuming Guaianaza syn. nov.), Parataygetis, Posttaygetis, Harjesia (excluding Harjesia griseola and Harjesia oreba), Pseudodebis (including Taygetomorpha syn. nov.,), Taygetina (subsuming Coeruleotaygetis syn. nov., Harjesia oreba comb. nov., Taygetis weymeri comb. nov. and Taygetis kerea comb. nov.), Taygetis (excluding Taygetis ypthima, Taygetis rectifascia, Taygetis kerea and Taygetis weymeri), and two new genera, one containing Harjesia griseola, and the other Taygetis ypthima and Taygetis rectifascia. The group diversified mainly during late Miocene to Pliocene, coinciding with the period of drastic changes in landscape configuration in the Neotropics. Major dispersals inferred from the Amazon basin towards northwestern South America, the Atlantic forests and the eastern slope of the Andes have mostly shaped the evolution and diversification of the group. Furthermore, expansion of larval dietary repertoire might have aided net diversification in the two largest genera in the clade, Forsterinaria and Taygetis. 相似文献
92.
Consuelo Sandoval José M. Méndez Rubén Sánchez-Obregón Carmen B. Alpízar 《Biocatalysis and Biotransformation》2013,31(1):36-44
Cultured plant cells from Taxus brevifolia Nutt and Taxus globosa Schltdl were investigated as biocatalysts using exogenous substrates. Production of highly specific metabolites by these species prompted us to analyse their synthetic potential. Whole cells suspensions have the capacity to chemoselectively reduce ethyl acetoacetate to ethyl 3-hydroxybutyrate chemo- and stereoselectively reduce rac-2-benzoylcyclohexanone to (1R, 2S)- and (1S, 2S)-2-hydroxycyclohexylphenylmethanones, and to cyclize N-phthaloyl-L-glutamine to thalidomide. 相似文献
93.
Borja Cascales-Mi?ana Jesús Mu?oz-Bertomeu María Flores-Tornero Armand Djoro Anoman José Pertusa Manuel Alaiz Sonia Osorio Alisdair R. Fernie Juan Segura Roc Ros 《The Plant cell》2013,25(6):2084-2101
This study characterizes the phosphorylated pathway of Ser biosynthesis (PPSB) in Arabidopsis thaliana by targeting phosphoserine phosphatase (PSP1), the last enzyme of the pathway. Lack of PSP1 activity delayed embryo development, leading to aborted embryos that could be classified as early curled cotyledons. The embryo-lethal phenotype of psp1 mutants could be complemented with PSP1 cDNA under the control of Pro35S (Pro35S:PSP1). However, this construct, which was poorly expressed in the anther tapetum, did not complement mutant fertility. Microspore development in psp1.1/psp1.1 Pro35S:PSP1 arrested at the polarized stage. The tapetum from these lines displayed delayed and irregular development. The expression of PSP1 in the tapetum at critical stages of microspore development suggests that PSP1 activity in this cell layer is essential in pollen development. In addition to embryo death and male sterility, conditional psp1 mutants displayed a short-root phenotype, which was reverted in the presence of Ser. A metabolomic study demonstrated that the PPSB plays a crucial role in plant metabolism by affecting glycolysis, the tricarboxylic acid cycle, and the biosynthesis of amino acids. We provide evidence of the crucial role of the PPSB in embryo, pollen, and root development and suggest that this pathway is an important link connecting primary metabolism with development. 相似文献
94.
95.
Guillaume Allorent Ryutaro Tokutsu Thomas Roach Graham Peers Pierre Cardol Jacqueline Girard-Bascou Daphné Seigneurin-Berny Dimitris Petroutsos Marcel Kuntz Cécile Breyton Fabrice Franck Francis-André Wollman Krishna K. Niyogi Anja Krieger-Liszkay Jun Minagawa Giovanni Finazzi 《The Plant cell》2013,25(2):545-557
Absorption of light in excess of the capacity for photosynthetic electron transport is damaging to photosynthetic organisms. Several mechanisms exist to avoid photodamage, which are collectively referred to as nonphotochemical quenching. This term comprises at least two major processes. State transitions (qT) represent changes in the relative antenna sizes of photosystems II and I. High energy quenching (qE) is the increased thermal dissipation of light energy triggered by lumen acidification. To investigate the respective roles of qE and qT in photoprotection, a mutant (npq4 stt7-9) was generated in Chlamydomonas reinhardtii by crossing the state transition–deficient mutant (stt7-9) with a strain having a largely reduced qE capacity (npq4). The comparative phenotypic analysis of the wild type, single mutants, and double mutants reveals that both state transitions and qE are induced by high light. Moreover, the double mutant exhibits an increased photosensitivity with respect to the single mutants and the wild type. Therefore, we suggest that besides qE, state transitions also play a photoprotective role during high light acclimation of the cells, most likely by decreasing hydrogen peroxide production. These results are discussed in terms of the relative photoprotective benefit related to thermal dissipation of excess light and/or to the physical displacement of antennas from photosystem II. 相似文献
96.
We studied the population and feeding ecology of the kelp crab Taliepus marginatus in subtidal kelp forests dominated by either of two morphologically different kelp species (Macrocystis pyrifera or Lessonia trabeculata) in northern Chile. The sizes and abundances of T. marginatus differed between the two kelp habitats. Kelp crabs were more abundant in the M. pyrifera forest than in the L. trabeculata forest. Size‐frequency distributions showed that juvenile and immature crabs were more common in the M. pyrifera forest than in the L. trabeculata forest, where reproductive adults predominated. The smaller crabs in the M. pyrifera habitat also consumed a higher proportion of kelp tissues than the larger crabs in the L. trabeculata habitat, which had a higher proportion of animal food in their diet. In both kelp forests, individuals of T. marginatus showed a similar pattern of nocturnal feeding over a 24‐h period, consuming more food at night than during the day. The more complex and dense forests of M. pyrifera appear to present better nursery habitats for juvenile kelp crabs than the more open and less dense forests dominated by L. trabeculata. These results suggest that the role of the two kelp habitats for T. marginatus varies during the life cycle of the kelp crabs, with M. pyrifera tending to have nursery function and L. trabeculata being more suitable as a reproductive habitat. 相似文献
97.
98.
For a long time, Cercosaura ocellata was considered polytypic, with three subspecies: C. ocellata ocellata, C. ocellata petersi and C. ocellata bassleri. Recently, C. ocellata bassleri was elevated to full species, based on analysis of a few molecular samples from Peru. This species complex is widely distributed in South America, occurring in Amazonia, Cerrado, Atlantic forest and Pampa biomes. The monophyly and species diversity of C. ocellata are still unstudied. Here, we infer phylogenetic relationships and species diversity of this group analysing 2326 base pairs of three mitochondrial (12S, 16S, and ND4) and one nuclear (c-mos) genes. Our taxon sampling of 115 specimens includes 72 samples of C. ocellata and sequences of other Cercosaura species and closely related Cercosaurinae. Maximum likelihood phylogenetic analysis recovered the monophyly of Cercosaura and that of C. ocellata with strong support. Our analyses suggest that C. ocellata is a complex of cryptic species, which possibly started diversifying in Amazonia. 相似文献
99.
André B. P. van Kuilenburg Heinz-Josef Klumpen Anneke M. Westermann Lida Zoetekouw Piet J. M. Bakker Henk-Jan Guchelaar 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):726-732
Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the metabolism of 5-fluorouracil (5FU). In patients treated with capecitabine or 5FU combined with other chemotherapeutic drugs, DPD activity in peripheral blood mononuclear cells was increased in patients experiencing grade I/II neutropenia. In contrast, decreased DPD activity proved to be associated with grade I/II dermatological toxicity, including hand-foot syndrome. Thus, patients with a low-normal or high-normal DPD activity proved to be at risk of developing mild toxicity upon treatment with 5FU-based chemotherapy, demonstrating the important role of DPD in the etiology of toxicity associated with 5FU and the catabolites of 5FU. 相似文献
100.
Cristiano Agra Iserhard Keith Spalding Brown Jr. André Victor Lucci Freitas 《Journal of Insect Conservation》2013,17(3):615-622
There are few papers describing long-term fluctuations and general patterns of temporal diversity in butterfly assemblages in the Neotropical region. The present paper presents a long-term study on the variation in richness and composition of butterflies in a fragment of semi-deciduous forest in Southeastern Brazil, and examines the viability of using maximized butterfly transect counts as a methodology to rapidly and adequately access the local characteristics of butterfly communities. Based on the eight annual standard lists, 518 species in six butterfly families were recorded, representing 74 % of the total butterfly fauna known from the study site. Hesperiidae was the richest family (248 species), followed by Nymphalidae (154), Lycaenidae (49), Riodinidae (29), Pieridae (26), and Papilionidae (12). The accumulation curves show that 8 years of sampling were not enough to result in stable species totals for all butterfly families, especially Hesperiidae and Lycaenidae, which are still increasing in number of species. A great similarity in species composition was observed among all the years (54 %). Comparing the similarity between two standard lists at different time intervals (from 1 to 8 years), a clear pattern of increasing dissimilarity was observed in most families. Our results show that the maximized sampling method is effective in revealing temporal patterns of diversity across several years and could be valuable in monitoring temporal variation in butterfly assemblages for conservation purposes, since the obtained standard lists can be successfully compared to temporal patterns over large periods of time. 相似文献