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991.
Gema López-Torrejón Davide Guerra Rafael Catal Julio Salinas Juan C. del Pozo 《植物学报(英文版)》2013,55(1):96-107
Post-translational modifications (PTMs) chemically and physically alter the properties of proteins, including their folding, subcellular localization, stability, activity, and consequently their function. In spite of their relevance, studies on PTMs in plants are still limited. Small Ubiquitin-like Modifier (SUMO) modification regulates several biological processes by affecting protein-protein interactions, or changing the subcellular localizations of the target proteins. Here, we describe a novel proteomic approach to identify SUMO targets that combines 2-D liquid chromatography, immunodetection, and mass spectrometry (MS) analyses. We have applied this approach to identify nuclear SUMO targets in response to heat shock. Using a bacterial SUMOylation system, we validated that some of the targets identified here are, in fact, labeled with SUMO1. Interestingly, we found that GIGANTEA (GI), a photoperiodic-pathway protein, is modified with SUMO in response to heat shock both in vitro and in vivo. 相似文献
992.
Arantza MuguruzaMontero Rafael Ramis Eider Nuez Oscar R. Ballesteros Markel G. Ibarluzea Ariane Araujo Sara MAlicante Janire Urrutia Aritz Leonardo Aitor Bergara Alvaro Villarroel 《Protein science : a publication of the Protein Society》2021,30(10):2029
Most calmodulin (CaM) targets are α‐helices. It is not clear if CaM induces the adoption of an α‐helix configuration to its targets or if those targets are selected as they spontaneously adopt an α‐helical conformation. Other than an α‐helix propensity, there is a great variety of CaM targets with little more in common. One exception to this rule is the IQ site that can be recognized in a number of targets, such as those ion channels belonging to the KCNQ family. Although there is negligible sequence similarity between the IQ motif and the docking site on SK2 channels, both adopt a similar three‐dimensional disposition. The isolated SK2 target presents a pre‐folded core region that becomes fully α‐helical upon binding to CaM. The existence of this pre‐folded state suggests the occurrence of capping within CaM targets. In this review, we examine the capping properties within the residues flanking this core domain, and relate known IQ motifs and capping. 相似文献
993.
Rafael Jaime Julio M. Alc ntara Jesú s M. Bastida Pedro J. Rey 《Journal of Plant Ecology》2015,8(5):457
Aims This study explores the patterns of niche differentiation in a group of seven closely related columbines (genus Aquilegia, Ranunculaceae) from the Iberian Peninsula. Populations of these columbines are subject to complex patterns of divergent selection across environments, which partly explain the taxonomic structure of the group. This suggests the hypothesis that niche divergence must have occurred along the process of diversification of the group.Methods We used MaxEnt to build environmental niche models of seven subspecies belonging to the three species of Aquilegia present in the Iberian Peninsula. From these models, we compared the environmental niches through two different approaches: ENMtools and multivariate methods.Important findings MaxEnt distributions conformed closely to the actual distribution of the study taxa. ENMtools methods failed to uncover any clear patterns of niche differentiation or conservatism in Iberian columbines. Multivariate analyses indicate the existence of differentiation along altitudinal gradients and along a gradient of climatic conditions determined by the summer precipitation and temperatures. However, climatic conditions related to winter temperature and precipitation, as well as soil properties, were equally likely to show conservatism or divergence. The complex patterns of niche evolution we found suggest that Iberian Columbines have not been significantly constrained by forces of niche conservatism, so they could respond adaptively to the fast and profound climate changes in the Iberian Peninsula through the glacial cycles of the Pleistocene. 相似文献
994.
Dario Rafael Olicón-Hernández Pedro Alberto Vázquez-Landaverde Ramón Cruz-Camarillo 《Preparative biochemistry & biotechnology》2017,47(2):116-122
Bacillus thuringiensis is a nonhuman pathogen bacterium that is used as a fungal and insect biocontrol agent. Because of its environmental interaction, it possesses several extracellular enzymes that are able to degrade chitin and chitosan, two of the most important polymers because of their application in numerous fields. However, in recent years, it has been observed that oligosaccharides from the enzymatic degradation of chitosan have important benefits for human health. Comparison and exploration of the production of chito-oligosaccharides from different sources of chitosan will improve the process parameters and expand the biotechnology based in these molecules. This study shows the production of chito-oligosaccharides from three different sources of colloidal chitosan and conducts a qualitative–quantitative comparison between them, using the extracellular enzyme of B. thuringiensis. We found that in the three substrates, it is possible to get a mixture of chito-oligosaccharides from dimer to hexamer in a concentration range from 0.72 to 8.09?mg?·?g?1 of original substrate. The best substrate to obtain these molecules was commercial chitosan as it has the highest production yields. 相似文献
995.
996.
Polymorphisms in HLA‐DQ genes,together with age,sex, and Helicobacter pylori infection,as potential biomarkers for the early diagnosis of gastric cancer
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997.
998.
Yaira Barranco-Ruiz Antonio Martínez-Amat Cristina Casals Jerónimo Aragón-Vela Silvia Rosillo Silvana N. Gomes Ana Rivas-García Rafael Guisado Jesús R. Huertas 《Journal of physiology and biochemistry》2017,73(1):37-48
The effect of exercise-induced oxidative stress on health and aging is not clearly explained. This study examined the effects of habitual sport practice, age, and submaximal exercise on the blood markers of oxidative stress, muscle damage, and antioxidant response. Seventy-two healthy men were grouped by their habitual sport practice: inactive (<1.5 h/week), recreational (3–8 h/week), and trained athletes (>8 h/week), and further divided by age: young (18–25 years), adult (40–55 years), and senior (>55 years). Blood samples were collected at rest and after submaximal effort. Hydroperoxides and superoxide dismutase, glutathione peroxidase, and catalase activities were measured by spectrophotometry. Nuclear DNA damage was analyzed by comet assay. The alpha-actin release was analyzed by Western blot. Alpha-tocopherol, retinol, and coenzyme-Q10 were quantified by high-performance liquid chromatography analysis. Data was analyzed through a factorial ANOVA and the Bonferroni post hoc test. Lipid peroxidation increased significantly with age and submaximal effort (p?<?0.05). However, the trained athlete group presented lower lipid peroxidation compared with the recreational group (MD?=?2.079, SED?=?0.58, p?=?0.002) and inactive group (MD?=?1.979, SED?=?0.61, p?=?0.005). Trained athletes showed significant higher alpha-actin levels (p?<?0.001) than the other groups. Recreational group showed lower nuclear DNA damage than trained athletes (MD?=?3.681, SED?=?1.28, p?=?0.015). Nevertheless, the inactive group presented significantly higher superoxide dismutase and catalase (p?<?0.05) than the other groups. Data suggested that habitual competitive training practice could prevent age-related increases of plasma lipid peroxidation, which, according with our results, cannot be entirely attributed to blood antioxidant defense systems. 相似文献
999.
1000.
Global patterns of β‐diversity along the phylogenetic time‐scale: The role of climate and plate tectonics
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