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71.

Purpose

To compare the effects of endurance exercise performed in the morning and evening on inflammatory cytokine responses in young men.

Methods

Fourteen healthy male participants aged 24.3 ± 0.8 years (mean ± standard error) performed endurance exercise in the morning (0900–1000 h) on one day and then in the evening (1700–1800 h) on another day with an interval of at least 1 week between each trial. In both the morning and evening trials, the participants walked for 60 minutes at approximately 60% of the maximal oxygen uptake (V·O2max) on a treadmill. Blood samples were collected to determine hormones and inflammatory cytokines at pre-exercise, immediately post exercise, and 2 h post exercise.

Results

Plasma interleukin (IL)-6 and adrenaline concentrations were significantly higher immediately after exercise in the evening trial than in the morning trial (P < 0.01, both). Serum free fatty acids concentrations were significantly higher in the evening trial than in the morning trial at 2 h after exercise (P < 0.05). Furthermore, a significant correlation was observed between the levels of IL-6 immediately post-exercise and free fatty acids 2 h post-exercise in the evening (r = 0.68, P < 0.01).

Conclusions

These findings suggest that the effect of acute endurance exercise in the evening enhances the plasma IL-6 and adrenaline concentrations compared to that in the morning. In addition, IL-6 was involved in increasing free fatty acids, suggesting that the evening is more effective for exercise-induced lipolysis compared with the morning.  相似文献   
72.

Background

Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals.

Methods

We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle.

Results

The 50% effective inhibitory concentration (IC50) of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus.

Conclusions

To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-μM) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent.  相似文献   
73.
74.
The endogenous trans-acting small interfering RNA (ta-siRNA) pathway plays a conserved role in adaxial-abaxial patterning of lateral organs in simple-leafed plant species. However, its function in compound-leafed species is largely unknown. Using the compound-leafed species Lotus japonicus, we identified and characterized two independent mutants, reduced leaflet1 (rel1) and rel3, whose most conspicuous defects in compound leaves are abaxialized leaflets and reduction in leaflet number. Concurrent mutations in REL genes also compromise flower development and result in radial symmetric floral organs. Positional cloning revealed that REL1 and REL3 encode the homologs of Arabidopsis (Arabidopsis thaliana) SUPPRESSOR OF GENE SILENCING3 and ARGONAUTE7/ZIPPY, respectively, which are key components of the ta-siRNA pathway. These observations, together with the expression and functional data, demonstrated that the ta-siRNA pathway plays conserved yet distinct roles in the control of compound leaf and flower development in L. japonicus. Moreover, the phenotypic alterations of lateral organs in ta-siRNA-deficient mutants and the regulation of downstream targets by the ta-siRNA pathway in L. japonicus were similar to those in the monocots but different from Arabidopsis, indicating many parallels between L. japonicus and the monocots in the control of lateral organ development by the ta-siRNA pathway.Plant endogenous small RNAs can be categorized into microRNAs (miRNAs) and small interfering RNAs (siRNAs) according to their mechanism of biogenesis (Vaucheret, 2006). trans-Acting siRNAs (ta-siRNAs) are one type of siRNA, and their biogenesis requires several key components, such as SUPPRESSOR OF GENE SILENCING3 (SGS3), RNA-DEPENDENT RNA POLYMERASE6 (RDR6), DICER-LIKE4 (DCL4), ARGONAUTE7 (AGO7)/ZIPPY (ZIP), and dsRNA-BINDING4 (Peragine et al., 2004; Vazquez et al., 2004; Gasciolli et al., 2005; Xie et al., 2005; Yoshikawa et al., 2005; Adenot et al., 2006; Nakazawa et al., 2007). Recent studies revealed that the ta-siRNA pathway is integrated into different processes of plant development, such as vegetative phase transition in Arabidopsis (Arabidopsis thaliana; Hunter et al., 2003; Peragine et al., 2004; Xie et al., 2005; Nakazawa et al., 2007) and shoot apical meristem (SAM) initiation in rice (Oryza sativa; Satoh et al., 1999; Itoh et al., 2000; Nagasaki et al., 2007). Parallel studies of this pathway in simple-leafed species also showed that the ta-siRNA pathway plays critical roles in patterning of leaves and floral organs.In flowering plants, leaves and flowers are produced on the periphery of the apical meristem. These lateral organs are structurally asymmetric with regard to the apical meristem. The adaxial side is adjacent to the meristem, while the abaxial side is away from the meristem. The ta-siRNA pathway was found to play a conserved role in specifying the adaxial identity of lateral organs in both monocots and dicots, but defects in the ta-siRNA pathway caused more severe phenotypes in monocots than in dicot Arabidopsis. In Arabidopsis, no clear leaf polarity defects were detected in the ta-siRNA-defective mutants. However, blocking the ta-siRNA pathway in asymmetric1 (as1) or as2 background, which are regulators of leaf adaxial identity (Lin et al., 2003; Xu et al., 2003), results in enhanced adaxial-abaxial leaf defects (Li et al., 2005; Xu et al., 2006; Garcia et al., 2006). In addition, the as2rdr6 double mutants also display aberrant flowers with sepals failing to enwrap the inner whorl organs and some sepals and petals becoming needle-like structures (Li et al., 2005). In maize (Zea mays), mutations in LEAFBLADELESS1 (LBL1), which encodes the Arabidopsis SGS3 ortholog, give rise to abnormal leaves with partial or complete loss of adaxial cell identity (Timmermans et al., 1998; Nogueira et al., 2007). In severe lbl1 mutants, leaf-like lateral organs of inflorescences and flowers develop as symmetric, thread-like organs, and the immature ear is exposed and arrested in development (Timmermans et al., 1998). In rice, the osdcl4-1 mutants display an abaxialized epidermis in coleoptiles and in the first leaf, and knockdown of OsDCL4 can lead to the awn-like lemma with a radial abaxialized identity and the stamens and carpel not enwrapped by the lemma and pelea (Liu et al., 2007). Transgenic rice plants with ectopic expression of SHOOTLESS4 (SHL4), the homolog of Arabidopsis AGO7, exhibit partially adaxialized leaves (Nagasaki et al., 2007; Shi et al., 2007).In addition to the ta-siRNA pathway, other components have also been shown to be involved in the adaxial-abaxial patterning of lateral organs. The Antirrhinum majus PHANTASTICA (PHAN) gene (Waites et al., 1998; Byrne et al., 2000; Xu et al., 2003; Qi et al., 2004), which is the ortholog of Arabidopsis AS1, and CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) gene family members (McConnell et al., 2001; Emery et al., 2003) contribute to adaxial pattern formation of lateral organs, whereas members of YABBY (YAB; Sawa et al., 1999; Siegfried et al., 1999) and KANADI (Eshed et al., 2001; Kerstetter et al., 2001) gene families, AUXIN RESPONSE FACTOR3 (ARF3) and ARF4 (Pekker et al., 2005), and the miRNAs miR165/166 (Emery et al., 2003; Eshed et al., 2004; Mallory et al., 2004) are required for specifying abaxial identity. How the activities of these adaxial and abaxial determinants are coordinated has been extensively studied. It was found that ARF3 and ARF4 are regulated by the TAS3 ta-siRNA, and this regulation is conserved in both monocots and dicots (Allen et al., 2005; Williams et al., 2005). Recent studies in Arabidopsis suggest that ta-siRNAs act in a non-cell-autonomous manner to spatially restrict ARF activity (Chitwood et al., 2009; Schwab et al., 2009).In contrast to simple leaves with their single lamina, compound leaves are composed of one petiole and several leaflets. It is found that genes required for the adaxial-abaxial patterning of lateral organs in simple-leafed species also play critical roles in compound-leafed species, but these genes play multiple roles in compound leaf development. In tomato (Solanum lycopersicum), down-regulation of PHAN ortholog disturbs the leaf polarity as well as leaflet formation (Kim et al., 2003). Extensive studies of the PHAN expression in diverse compound-leafed species suggest that the function of PHAN in maintaining leaf adaxial identity is associated with leaflet formation in compound leaves and reduced adaxial identity of leaf primordia by down-regulation of PHAN could change pinnate compound leaves into palmate leaves (Kim et al., 2003). In pea (Pisum sativum), the role of PHAN in compound leaf development has also been elucidated by characterization of the phan mutant crispa (cri; Tattersall et al., 2005). However, unlike antisense PHAN transgenic tomato leaves, the cri mutant has the individual leaflet abaxialized, rather than the whole leaf. The number of lateral organs on the cri mutant compound leaves, including leaflets, is not altered, and the leaves remain pinnate. Apart from leaf development, the cri mutation also affects flower development. Although the floral organ identity and organ number are not altered, the laminar floral organ display abaxialized identity (Tattersall et al., 2005).The ta-siRNA pathway plays a critical role in simple-leafed species, but its role in compound-leafed species is not understood. Here, we address this question by analyzing loss-of-function reduced leaflet (rel1) and rel3 mutants in the compound-leafed species Lotus japonicus. Phenotypic characterization shows compound leaves of rel mutants exhibit a conspicuous disturbance in leaflet polarity as well as reduction in leaflet number. Besides the abnormal compound leaves, flower development is also severely affected in rel mutants, showing radial symmetric petals. REL1 and REL3 were identified by map-based cloning and were shown to be homologs of Arabidopsis SGS3 and AGO7, respectively. REL1 and REL3 act in the same genetic pathway and are both required for the biogenesis of TAS3 ta-siRNA. Further investigation reveals that the homolog of the Arabidopsis ARF3 is duplicated in the L. japonicus genome and that the duplicate ARF3 homologs and the ARF4 homolog are all negatively regulated by the ta-siRNA pathway. Furthermore, we found that the expression of LjYAB1, a homolog of Arabidopsis YAB1, was decreased in rel mutants, which may be associated with the reduced lamina.Taken together, our data reveal that the ta-siRNA pathway is integrated into the regulatory networks in the control of lateral organ development in L. japonicus and further emphasize the importance of the ta-siRNA pathway in compound leaf development. Moreover, our results also indicate many parallels between L. japonicus and monocots for the ta-siRNA pathway in the regulation of lateral organs.  相似文献   
75.
76.
In spite of its clinical and nutritional importance, l-alanyl-l-glutamine (Ala-Gln) has not been widely used due to the absence of an efficient manufacturing method. Here, we present a novel method for the fermentative production of Ala-Gln using an Escherichia coli strain expressing l-amino acid alpha-ligase (Lal), which catalyzes the formation of dipeptides by combining two amino acids in an ATP-dependent manner. Two metabolic manipulations were necessary for the production of Ala-Gln: reduction of dipeptide-degrading activity by combinatorial disruption of the dpp and pep genes and enhancement of the supply of substrate amino acids by deregulation of glutamine biosynthesis and overexpression of heterologous l-alanine dehydrogenase (Ald). Since expression of Lal was found to hamper cell growth, it was controlled using a stationary-phase-specific promoter. The final strain constructed was designated JKYPQ3 (pepA pepB pepD pepN dpp glnE glnB putA) containing pPE167 (lal and ald expressed under the control of the uspA promoter) or pPE177 (lal and ald expressed under the control of the rpoH promoter). Either strain produced more than 100 mM Ala-Gln extracellularly, in fed-batch cultivation on glucose-ammonium salt medium, without added alanine and glutamine. Because of the characteristics of Lal, no longer peptides (such as tripeptides) or dipeptides containing d-amino acids were formed.  相似文献   
77.
Animal and yeast nucleolin function as global regulators of ribosome synthesis, and their expression is tightly linked to cell proliferation. Although Arabidopsis contains two genes for nucleolin, AtNuc-L1 is the predominant if not only form of the protein found in most tissues, and GFP-AtNuc-L1 fusion proteins were targeted to the nucleolus. Expression of AtNuc-L1 was strongly induced by sucrose or glucose but not by non-metabolizable mannitol or 2-deoxyglucose. Sucrose also caused enhanced expression of genes for subunits of C/D and H/ACA small nucleolar ribonucleoproteins, as well as a large number of genes for ribosomal proteins (RPs), suggesting that carbohydrate availability regulates de novo ribosome synthesis. In sugar-starved cells, induction of AtNuc-L1 occurred with 10 mM glucose, which seemed to be a prerequisite for resumption of growth. Disruption of AtNuc-L1 caused an increased steady-state level of pre-rRNA relative to mature 25S rRNA, and resulted in various phenotypes that overlap those reported for several RP gene mutants, including a reduced growth rate, prolonged lifetime, bushy growth, pointed leaf, and defective vascular patterns and pod development. These results suggest that the rate of ribosome synthesis in the meristem has a strong impact not only on the growth but also the structure of plants. The AtNuc-L1 disruptant exhibited significantly reduced sugar-induced expression of RP genes, suggesting that AtNuc-L1 is involved in the sugar-inducible expression of RP genes.  相似文献   
78.
Protein-protein interactions (PPIs) play crucial roles in protein function for a variety of biological processes. Data from large-scale PPI screening has contributed to understanding the function of a large number of predicted genes from fully sequenced genomes. Here, we report the systematic identification of protein interactions for the unicellular cyanobacterium Synechocystis sp. strain PCC6803. Using a modified high-throughput yeast two-hybrid assay, we screened 1825 genes selected primarily from (i) genes of two-component signal transducers of Synechocystis, (ii) Synechocystis genes whose homologues are conserved in the genome of Arabidopsis thaliana, and (iii) genes of unknown function on the Synechocystis chromosome. A total of 3236 independent two-hybrid interactions involving 1920 proteins (52% of the total protein coding genes) were identified and each interaction was evaluated using an interaction generality (IG) measure, as well as the general features of interacting partners. The interaction data obtained in this study should provide new insights and novel strategies for functional analyses of genes in Synechocystis, and, additionally, genes in other cyanobacteria and plant genes of cyanobacterial origin.  相似文献   
79.
In order to reveal quantitative trait loci (QTL) interactions and the relationship between various interactions in complex traits, we have developed a new QTL mapping approach, named genotype matrix mapping (GMM), which searches for QTL interactions in genetic variation. The central approach in GMM is the following. (1) Each tested marker is given a virtual matrix, named a genotype matrix (GM), containing intersecting lines and rows equal to the total allele number for that marker in the population analyzed. (2) QTL interactions are then estimated and compared through virtual networks among the GMs. To evaluate the contribution of marker combinations to a quantitative phenotype, the GMM method divides the samples into two non-overlapping subclasses, S(0) and S(1); the former contains the samples that have a specific genotype pattern to be evaluated, and the latter contains samples that do not. Based on this division, the F-measure is calculated as an index of significance. With the GMM method, we extracted significant marker combinations consisting of one to three interacting markers. The results indicated there were multiple QTL interactions affecting the phenotype (flowering date). GMM will be a valuable approach to identify QTL interactions in genetic variation of a complex trait within a variety of organisms.  相似文献   
80.
The first quantitative trait locus (QTL) analysis of multiple agronomic traits in the model legume Lotus japonicus was performed with a population of recombinant inbred lines derived from Miyakojima MG-20 x Gifu B-129. Thirteen agronomic traits were evaluated in 2004 and 2005: traits of vegetative parts (plant height, stem thickness, leaf length, leaf width, plant regrowth, plant shape, and stem color), flowering traits (flowering time and degree), and pod and seed traits (pod length, pod width, seeds per pod, and seed mass). A total of 40 QTLs were detected that explained 5%-69% of total variation. The QTL that explained the most variation was that for stem color, which was detected in the same region of chromosome 2 in both years. Some QTLs were colocated, especially those for pod and seed traits. Seed mass QTLs were located at 5 locations that mapped to the corresponding genomic positions of equivalent QTLs in soybean, pea, chickpea, and mung bean. This study provides fundamental information for breeding of agronomically important legume crops.  相似文献   
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