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951.
Identification and functional characterization of the Arabidopsis Snf1‐related protein kinase SnRK2.4 phosphatidic acid‐binding domain 下载免费PDF全文
MAGDALENA M. JULKOWSKA FIONN MCLOUGHLIN CARLOS S. GALVAN‐AMPUDIA JOHANNA M. RANKENBERG DOROTA KAWA MARIA KLIMECKA MICHEL A. HARING TEUN MUNNIK EDGAR E. KOOIJMAN CHRISTA TESTERINK 《Plant, cell & environment》2015,38(3):614-624
Phosphatidic acid (PA) is an important signalling lipid involved in various stress‐induced signalling cascades. Two SnRK2 protein kinases (SnRK2.4 and SnRK2.10), previously identified as PA‐binding proteins, are shown here to prefer binding to PA over other anionic phospholipids and to associate with cellular membranes in response to salt stress in Arabidopsis roots. A 42 amino acid sequence was identified as the primary PA‐binding domain (PABD) of SnRK2.4. Unlike the full‐length SnRK2.4, neither the PABD‐YFP fusion protein nor the SnRK2.10 re‐localized into punctate structures upon salt stress treatment, showing that additional domains of the SnRK2.4 protein are required for its re‐localization during salt stress. Within the PABD, five basic amino acids, conserved in class 1 SnRK2s, were found to be necessary for PA binding. Remarkably, plants overexpressing the PABD, but not a non‐PA‐binding mutant version, showed a severe reduction in root growth. Together, this study biochemically characterizes the PA–SnRK2.4 interaction and shows that functionality of the SnRK2.4 PABD affects root development. 相似文献
952.
Woo Jong Choi Misun Kim Ji‐Youn Park Tae Jun Park Hee Young Kang 《Pigment cell & melanoma research》2015,28(1):51-60
Pleiotrophin (PTN) is a secreted heparin‐binding protein that is involved in various biological functions of cell growth and differentiation. Little is known about the effects of PTN on the melanocyte function and skin pigmentation. In this study, we investigated whether PTN would affect melanogenesis. PTN was expressed in melanocytes and fibroblasts of human skin. Transfection studies revealed that PTN decreased melanogenesis, probably through MITF degradation via Erk1/2 activation in melanocytes. The inhibitory action of PTN in pigmentation was further confirmed in ex vivo cultured skin and in the melanocytes cocultured with fibroblasts. These findings suggest that PTN is a crucial factor for the regulation of melanogenesis in the skin. 相似文献
953.
Linking larval nutrition to adult reproductive traits in the European corn borer Ostrinia nubilalis 下载免费PDF全文
Throughout an organism's lifetime, resources are strategically allocated to many different functions, including reproduction. Reproduction can be costly for both sexes; females produce nutrient‐rich eggs, whereas males of many species produce large and complex ejaculates. In capital breeding insects, nutrients are mainly acquired during the larval period, yet allocation decisions impact the reproductive fitness of adults. The present study examines the effect of larval dietary nitrogen on both male and female reproductive traits in the European corn borer moth Ostrinia nubilalis Hübner, whose adults do not feed and whose males transfer a large, nitrogen‐rich spermatophore. One day post‐eclosion, O. nubilalis adults reared on one of three different diets (3.0%, 1.6%, or 1.1% nitrogen) are mated and two experiments are undertaken: one to measure nitrogen and carbon content of male ejaculates, and the other to determine female fecundity and fertility. Although male larval diet does not alter the percentage nitrogen content of adult somatic tissue, males reared on the higher nitrogen diet (3.0%) produce spermatophores with increased nitrogen relative to somatic nitrogen. Furthermore, females raised on the 3.0% nitrogen diet receive spermatophores with lower carbon : nitrogen ratios and thus more nitrogen. Overall, females lay more eggs as their larval dietary nitrogen increases, although they lay fewer eggs when their mates are raised on the higher (3.0%) nitrogen diet. This suggests that O. nubilalis females may use male‐derived nitrogen not to supplement egg production, but rather for somatic maintenance. Overall, the present study furthers our understanding of how larval diet can affect adult fitness in Lepidoptera. 相似文献
954.
The type of competition modulates the ecophysiological response of grassland species to elevated CO2 and drought 下载免费PDF全文
J. Miranda‐Apodaca U. Pérez‐López M. Lacuesta A. Mena‐Petite A. Muñoz‐Rueda 《Plant biology (Stuttgart, Germany)》2015,17(2):298-310
The effects of elevated CO2 and drought on ecophysiological parameters in grassland species have been examined, but few studies have investigated the effect of competition on those parameters under climate change conditions. The objective of this study was to determine the effect of elevated CO2 and drought on the response of plant water relations, gas exchange, chlorophyll a fluorescence and aboveground biomass in four grassland species, as well as to assess whether the type of competition modulates that response. Elevated CO2 in well‐watered conditions increased aboveground biomass by augmenting CO2 assimilation. Drought reduced biomass by reducing CO2 assimilation rate via stomatal limitation and, when drought was more severe, also non‐stomatal limitation. When plants were grown under the combined conditions of elevated CO2 and drought, drought limitation observed under ambient CO2 was reduced, permitting higher CO2 assimilation and consequently reducing the observed decrease in aboveground biomass. The response to climate change was species‐specific and dependent on the type of competition. Thus, the response to elevated CO2 in well‐watered grasses was higher in monoculture than in mixture, while it was higher in mixture compared to monoculture for forbs. On the other hand, forbs were more affected than grasses by drought in monoculture, while in mixture the negative effect of drought was higher in grasses than in forbs, due to a lower capacity to acquire water and mineral nutrients. These differences in species‐level growth responses to CO2 and drought may lead to changes in the composition and biodiversity of the grassland plant community in future climate conditions. 相似文献
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956.
Systematics and biogeography of Pleurobranchus Cuvier, 1804 sea slugs (Heterobranchus: Nudipleura: Pleurobranchidae). Addendum 下载免费PDF全文
957.
采用乙醇提取,用分光光度法测定的方法,以红柄白鹃梅为原料,通过正交试验研究了乙醇浓度,提取温度,提取时间和料液比4个因素对提取红柄白鹃梅叶片中总黄酮含量的影响。研究结果表明,各试验因素对红柄白鹃梅叶中黄酮类物质提取量的影响依料液比、提取温度、乙醇浓度、提取时间因素顺次降低,当提取温度为70℃、提取时间为2 h、料液比为1∶20时,提取效果最好,黄酮类物质提取量为22.412 mg/g。 相似文献
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