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991.
Ehsan Rakhshani Xavier Pons Belén Lumbierres Jan Havelka Nicolás Pérez Hidalgo Željko Tomanović 《Journal of Natural History》2017,51(21-22):1237-1248
A long-term survey of tritrophic (plant–aphid–parasitoid) associations in the urban ecosystems of Lleida (Catalonia) and Paris (France) resulted in the detection of associations of two bamboo aphids, Takecallis arundinariae (Essig) and Takecallis taiwanus (Takahashi), respectively, with a new aphid parasitoid species. Trioxys remaudierei Starý & Rakhshani sp. nov. is described and illustrated as a unique parasitoid of Takecallis aphids outside the area of their origin. The new species is easily distinguishable from its congeners in having the ventral prongs of the abdomen fused over two-thirds of their length, then bifurcated towards the tip. The only morphologically similar species is Trioxys betulae (Marshall), which exhibits a clearly different prong shape (and has a different host range, Symydobius Mordvilko and Clethrobius Mordvilko). The new species is compared with allied taxa associated with bamboo aphids. The occurrence of Takecallis taiwanus on bamboo is recorded in France for the first time.
www.zoobank.org/urn:lsid:zoobank.org:pub:ED15BA16-E8A9-4CEA-BDA7-FBAB02FEB091 相似文献
992.
Marcelo S. Perlin João F. Caldeira André A. P. Santos Martin Pontuschka 《Journal of forecasting》2017,36(4):454-467
We look into the interaction of Google's search queries and several aspects of international equity markets. Using a novel methodology for selecting words and a vector autoregressive modeling approach, we study whether the search queries of finance‐related words can have an impact on returns, volatility of returns and traded volume in four different English‐speaking countries. We identify several words whose search frequency is associated with changes in the dependent variables. In particular, we find that increases in search queries including the word stock predict increased volatility and decreased index returns over the next week. On top of that, we investigate the performance of a market‐timing strategy based on the search frequency of this word and benchmark it against random words from the Word‐Net database and a naive buy‐and‐hold strategy. The results of this empirical application are positive and particularly stronger during the global crisis of 2009. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
993.
L. Dhers L. Ducassou J.-L. Boucher D. Mansuy 《Cellular and molecular life sciences : CMLS》2017,74(10):1859-1869
Cytochrome P450 2U1 (CYP2U1) exhibits several distinctive characteristics among the 57 human CYPs, such as its presence in almost all living organisms with a highly conserved sequence, its particular gene organization with only five exons, its major location in thymus and brain, and its protein sequence involving an unusually long N-terminal region containing 8 proline residues and an insert of about 20 amino acids containing 5 arginine residues after the transmembrane helix. Few substrates, including fatty acids, N-arachidonoylserotonin (AS), and some drugs, have been reported so far. However, its biological roles remain largely unknown, even though CYP2U1 mutations have been involved in some pathological situations, such as complicated forms of hereditary spastic paraplegia. These data together with its ability to hydroxylate some fatty acids and AS suggest its possible role in lipid metabolism. 相似文献
994.
Daniel P. Cardinali Daniel E. Vigo 《Cellular and molecular life sciences : CMLS》2017,74(21):3941-3954
A number of risk factors for cardiovascular disease including hyperinsulinemia, glucose intolerance, dyslipidemia, obesity, and elevated blood pressure are collectively known as metabolic syndrome (MS). Since mitochondrial activity is modulated by the availability of energy in cells, the disruption of key regulators of metabolism in MS not only affects the activity of mitochondria but also their dynamics and turnover. Therefore, a link of MS with mitochondrial dysfunction has been suspected since long. As a chronobiotic/cytoprotective agent, melatonin has a special place in prevention and treatment of MS. Melatonin levels are reduced in diseases associated with insulin resistance like MS. Melatonin improves sleep efficiency and has antioxidant and anti-inflammatory properties, partly for its role as a metabolic regulator and mitochondrial protector. We discuss in the present review the several cytoprotective melatonin actions that attenuate inflammatory responses in MS. The clinical data that support the potential therapeutical value of melatonin in human MS are reviewed. 相似文献
995.
Zhiqiang Ma Zhenlong Xin Wencheng Di Xiaolong Yan Xiaofei Li Russel J. Reiter Yang Yang 《Cellular and molecular life sciences : CMLS》2017,74(21):3989-3998
Ischemia/reperfusion (IR) injury occurs in many organs and tissues, and contributes to morbidity and mortality worldwide. Melatonin, an endogenously produced indolamine, provides a strong defense against IR injury. Mitochondrion, an organelle for ATP production and a decider for cell fate, has been validated to be a crucial target for melatonin to exert its protection against IR injury. In this review, we first clarify the mechanisms underlying mitochondrial dysfunction during IR and melatonin’s protection of mitochondria under this condition. Thereafter, special focus is placed on the protective actions of melatonin against IR injury in brain, heart, liver, and others. Finally, we explore several potential future directions of research in this area. Collectively, the information compiled here will serve as a comprehensive reference for the actions of melatonin in IR injury identified to date and will hopefully aid in the design of future research and increase the potential of melatonin as a therapeutic agent. 相似文献
996.
G. M. C. Janssen P. Schwertman T. A. T. Wanga R. S. Jahangir Tafrechi P. J. A. van den Broek A. K. Raap 《Cellular and molecular life sciences : CMLS》2009,66(4):721-730
Cytoplasmic translation is under sophisticated control but how cells adapt its rate to constitutive loss of mitochondrial
oxidative phosphorylation is unknown. Here we show that translation is repressed in cells with the pathogenic A3243G mtDNA
mutation or in mtDNA-less ρ0 cells by at least two distinct pathways, one transiently targeting elongation factor eEF-2 and the other initiation factor
eIF-2α constitutively. Under conditions of exponential cell growth and mammalian target of rapamycin (mTOR) activation, eEF-2
becomes transiently phosphorylated by an AMP-activated protein kinase (AMPK)-dependent pathway, especially high in mutant
cells. Independent of AMPK and mTOR, eIF-2α is constitutively phosphorylated in mutant cells, likely a signature of endoplasmic
reticulum (ER)-stress response induced by the loss of oxidative phosphorylation. While the AMPK/eEF-2K/eEF-2 pathway appears
to function in adaptation to physiological fluctuations in ATP levels in the mutant cells, the ER stress signified by constitutive
protein synthesis inhibition through eIF-2α-mediated repression of translation initiation may have pathobiochemical consequences.
Received 29 October 2008; received after revision 11 December 2008; accepted 16 December 2008 相似文献
997.
V. Le Fourn K. Gaplovska-Kysela B. Guhl R. Santimaria C. Zuber J. Roth 《Cellular and molecular life sciences : CMLS》2009,66(8):1434-1445
Little is known about the fate of machinery proteins of the protein quality control and endoplasmic reticulum(ER)-associated
degradation (ERAD). We investigated the degradation of the ERAD component EDEM1, which directs overexpressed misfolded glycoproteins
to degradation. Endogenous EDEM1 was studied since EDEM1 overexpression not only resulted in inappropriate occurrence throughout
the ER but also caused cytotoxic effects. Proteasome inhibitors had no effect on the clearance of endogenous EDEM1 in non-starved
cells. However, EDEM1 could be detected by immunocytochemistry in autophagosomes and biochemically in LC3 immuno-purified
autophagosomes. Furthermore, influencing the lysosome-autophagy pathway by vinblastine or pepstatin A/E64d and inhibiting
autophagosome formation by 3-methyladenine or ATGs short interfering RNA knockdown stabilized EDEM1. Autophagic degradation
involved removal of cytosolic Triton X-100-insoluble deglycosylated EDEM1, but not of EDEM1-containing ER cisternae. Our studies
demonstrate that endogenous EDEM1 in cells not stressed by the expression of a transgenic misfolded protein reaches the cytosol
and is degraded by basal autophagy.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 15 January 2009; received after revision 16 February 2009; accepted 17 February 2009
V. Le Fourn, K. Gaplovska-Kysela: These authors equally contributed to this work. 相似文献
998.
R. P. Massengo-Tiassé J. E. Cronan 《Cellular and molecular life sciences : CMLS》2009,66(9):1507-1517
The enoyl-acyl carrier protein reductase (ENR) is the last enzyme in the fatty acid elongation cycle. Unlike most enzymes
in this essential pathway, ENR displays an unusual diversity among organisms. The growing interest in ENRs is mainly due to
the fact that a variety of both synthetic and natural antibacterial compounds are shown to specifically target their activity.
The primary anti-tuberculosis drug, isoniazid, and the broadly used antibacterial compound, triclosan, both target this enzyme.
In this review, we discuss the diversity of ENRs, and their inhibitors in the light of current research progress.
Received 3 November 2008; received after revision 5 December 2008; accepted 8 December 2008 相似文献
999.
Functions and pathologies of BiP and its interaction partners 总被引:1,自引:1,他引:0
J. Dudek J. Benedix S. Cappel M. Greiner C. Jalal L. Müller R. Zimmermann 《Cellular and molecular life sciences : CMLS》2009,66(9):1556-1569
The endoplasmic reticulum (ER) is involved in a variety of essential and interconnected processes in human cells, including
protein biogenesis, signal transduction, and calcium homeostasis. The central player in all these processes is the ER-lumenal
polypeptide chain binding protein BiP that acts as a molecular chaperone. BiP belongs to the heat shock protein 70 (Hsp70)
family and crucially depends on a number of interaction partners, including co-chaperones, nucleotide exchange factors, and
signaling molecules. In the course of the last five years, several diseases have been linked to BiP and its interaction partners,
such as a group of infectious diseases that are caused by Shigella toxin producing E. coli. Furthermore, the inherited diseases Marinesco-Sj?gren syndrome, autosomal dominant polycystic liver disease, Wolcott-Rallison
syndrome, and several cancer types can be considered BiP-related diseases. This review summarizes the physiological and pathophysiological
characteristics of BiP and its interaction partners.
Received 20 November 2008; received after revision 09 December 2008; accepted 12 December 2008 相似文献
1000.
A. Shukla P. Chaurasia S. R. Bhaumik 《Cellular and molecular life sciences : CMLS》2009,66(8):1419-1433
Methylation of lysine residues of histones is associated with functionally distinct regions of chromatin, and, therefore,
is an important epigenetic mark. Over the past few years, several enzymes that catalyze this covalent modification on different
lysine residues of histones have been discovered. Intriguingly, histone lysine methylation has also been shown to be cross-regulated
by histone ubiquitination or the enzymes that catalyze this modification. These covalent modifications and their cross-talks
play important roles in regulation of gene expression, heterochromatin formation, genome stability, and cancer. Thus, there
has been a very rapid progress within past several years towards elucidating the molecular basis of histone lysine methylation
and ubiquitination, and their aberrations in human diseases. Here, we discuss these covalent modifications with their cross-regulation
and roles in controlling gene expression and stability.
Received 24 September 2008; received after revision 21 November 2008; accepted 28 November 2008 相似文献