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排序方式: 共有1413条查询结果,搜索用时 31 毫秒
51.
Mayra Domínguez-Pérez Arturo Simoni-Nieves Patricia Rosales Natalia Nuño-Lámbarri Mónica Rosas-Lemus Verónica Souza Roxana U. Miranda Leticia Bucio Salvador Uribe Carvajal Jens U. Marquardt Daekwan Seo Luis E. Gomez-Quiroz María Concepción Gutiérrez-Ruiz 《Journal of cellular physiology》2019,234(5):7213-7223
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Willian Batista‐Silva David B. Medeiros Accio Rodrigues‐Salvador Danilo M. Daloso Rebeca P. Omena‐Garcia Franciele Santos Oliveira Lilian Ellen Pino Lzaro Eustquio Pereira Peres Adriano Nunes‐Nesi Alisdair R. Fernie Agustín Zsgn Wagner L. Araújo 《Plant, cell & environment》2019,42(2):448-465
Auxin modulates a range of plant developmental processes including embryogenesis, organogenesis, and shoot and root development. Recent studies have shown that plant hormones also strongly influence metabolic networks, which results in altered growth phenotypes. Modulating auxin signalling pathways may therefore provide an opportunity to alter crop performance. Here, we performed a detailed physiological and metabolic characterization of tomato (Solanum lycopersicum) mutants with either increased (entire) or reduced (diageotropica—dgt) auxin signalling to investigate the consequences of altered auxin signalling on photosynthesis, water use, and primary metabolism. We show that reduced auxin sensitivity in dgt led to anatomical and physiological modifications, including altered stomatal distribution along the leaf blade and reduced stomatal conductance, resulting in clear reductions in both photosynthesis and water loss in detached leaves. By contrast, plants with higher auxin sensitivity (entire) increased the photosynthetic capacity, as deduced by higher Vcmax and Jmax coupled with reduced stomatal limitation. Remarkably, our results demonstrate that auxin‐sensitive mutants (dgt) are characterized by impairments in the usage of starch that led to lower growth, most likely associated with decreased respiration. Collectively, our findings suggest that mutations in different components of the auxin signalling pathway specifically modulate photosynthetic and respiratory processes. 相似文献
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Corentin Bochaton Renaud Boistel Sandrine Grouard Ivan Ineich Anne Tresset Salvador Bailon 《Historical Biology》2019,31(2):140-156
This paper aims to demonstrate how subfossil bone remains from Pleistocene and Holocene deposits can help to reconstruct the history of recently extinct taxa through the example of Pholidoscelis lizards from the Guadeloupe Islands in the French West Indies. To achieve this, we conducted a new anatomical and zooarchaeological study of fossil Pholidoscelis remains collected from 23 archaeological and paleontological deposits on the Guadeloupe Islands from which this genus is nowadays absent. Our results shed light on the past existence of large Pholidoscelis lizards on all the Guadeloupe islands but also on the difficulties of confident specific identification for these remains. Nevertheless, we suggest a possible past occurrence of the now extinct Pholidoscelis major on nearly all of the Guadeloupe islands. In addition, we identified a new Pholidoscelis species, Pholidoscelis turukaeraensis sp. nov., on Marie-Galante Island, where no Pholidoscelis lizards were previously reported. This new species underwent an increase in size after the end of the Pleistocene period, possibly due to reduced predation pressure. We also highlight the consumption of Pholidoscelis lizards by pre-Columbian Amerindians and the huge impact of European colonization, which led to the extinction of all these lizards in less than 300 years.http://zoobank.org/urn:lsid:zoobank.org:pub:15C39436-A083-483F-B35E-78807B606904 相似文献
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Ferreira EO Salvador MJ Pral EM Alfieri SC Ito IY Dias DA 《Zeitschrift für Naturforschung. C, Journal of biosciences》2004,59(7-8):499-505
A new aurone 1 and two known substances, aurantiamide acetate (2) and tiliroside (3), were isolated from the ethanolic extract of Gomphrena agrestis. The structural determination of 1 was based on spectroscopic and spectrometric data. The substance was defined as (E)-3'-O-beta-D-glucopyranosyl-4,5,6,4'-tetrahydroxy-7,2'-dimethoxyaurone. Biological activity of the ethanolic crude extract and isolated compounds against bacteria, fungi and Leishmania amazonensis amastigotes was evaluated. This appears to be the first report documenting aurone and aurantiamide compounds in the Amaranthaceae family. In the evaluation of biological activity the ethanolic extract of G. agrestis and compounds 1, 2, and 3 were shown to be active mainly against Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. 相似文献
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Cejas JR Almansa E Jérez S Bolaños A Felipe B Lorenzo A 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2004,139(2):209-216
To establish the changes which occur during embryogenesis and early larvae development, eggs, yolk-sac larvae (one day old larvae) and absorbed yolk-sac larvae (three day old larvae) of white sea bream were examined for lipid class and fatty acid composition. The development was characterized by a decrease in all lipid classes with the exception of phosphatidylserine (PS) and fatty free acids (FFA) which increased, and sphingomyelin (SM) which remained unchanged. The changes observed in lipid class content and the decrease in fatty acids in total lipid (TL) reflect the utilization and mobilization of lipids during both embryogenesis and early larvae development. Fluctuations in the relative composition of fatty acids in phosphatidylcholine (PC) during development suggest a selective bulk uptake and catabolism of fatty acids in this lipid class. Unlike PC, catabolism of triacylglycerol (TG) fatty acid appears to be non-selective. During development, the decrease in levels of polyunsaturated fatty acids (PUFA) eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic (22:6n-3, DHA) in total lipid denotes their utilization as energy substrate by Diplodus sargus larvae. 相似文献
60.
Cejas JR Almansa E Jérez S Bolaños A Samper M Lorenzo A 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2004,138(1):91-102
Total lipids (TL), lipid classes, and their associated fatty acids from muscle and liver of captive and wild mature female broodstocks were investigated in order to estimate the fatty acid requirements of white seabream (Diplodus sargus). The results showed that the percentage of triacylglycerol was higher in liver and muscle of captive fish than in wild fish. The distribution of phospholipid classes in liver and muscle of both fish groups was similar, phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol being the predominant lipid classes. The general pattern of fatty acid distribution in total lipid of liver and muscle from captive and wild fish was similar. However, the relative percentage of specific fatty acids differed in captive and wild fish. The most noteworthy difference was the lower proportion of arachidonic acid (20:4n-6, AA) and the higher proportion of eicosapentaenoic acid (20:5n-3, EPA) in liver and muscle of captive fish with respect to those of wild fish. The proportion of docosahexaenoic acid (22:6n-3, DHA) did not differ between the two fish groups. The differences in EPA and AA proportions between captive and wild fish implied that captive fish presented a higher EPA/AA ratio and a lower DHA/EPA ratio than wild fish. In general terms, in both liver and muscle, the differences in fatty acid composition observed for TL were extended to all lipid classes. The results suggest that the different AA, EPA and DHA proportions in liver and muscle between captive and wild broodstocks are attributed to different levels of these fatty acids in broodstock diets. 相似文献