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Hyperthermia is the result of an imbalance between total heat (metabolic heat and environmental heat) accumulated in the body and heat loss from the body, and is defined as a condition when core temperature rises above its normal range. This article will present an overview of syndromes associated with hyperthermia, through discussion of the etiology and pathophysiologic mechanisms that underlie those disorders. Emphasis will also be placed on the therapeutic measures to be taken in order to avert the complications of these disorders. 相似文献
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Irina Orlova Dinesh A. Nagegowda Christine M. Kish Michael Gutensohn Hiroshi Maeda Marina Varbanova Eyal Fridman Shinjiro Yamaguchi Atsushi Hanada Yuji Kamiya Alexander Krichevsky Vitaly Citovsky Eran Pichersky Natalia Dudareva 《The Plant cell》2009,21(12):4002-4017
Geranyl diphosphate (GPP), the precursor of many monoterpene end products, is synthesized in plastids by a condensation of dimethylallyl diphosphate and isopentenyl diphosphate (IPP) in a reaction catalyzed by homodimeric or heterodimeric GPP synthase (GPPS). In the heterodimeric enzymes, a noncatalytic small subunit (GPPS.SSU) determines the product specificity of the catalytic large subunit, which may be either an active geranylgeranyl diphosphate synthase (GGPPS) or an inactive GGPPS-like protein. Here, we show that expression of snapdragon (Antirrhinum majus) GPPS.SSU in tobacco (Nicotiana tabacum) plants increased the total GPPS activity and monoterpene emission from leaves and flowers, indicating that the introduced catalytically inactive GPPS.SSU found endogenous large subunit partner(s) and formed an active snapdragon/tobacco GPPS in planta. Bimolecular fluorescence complementation and in vitro enzyme analysis of individual and hybrid proteins revealed that two of four GGPPS-like candidates from tobacco EST databases encode bona fide GGPPS that can interact with snapdragon GPPS.SSU and form a functional GPPS enzyme in plastids. The formation of chimeric GPPS in transgenic plants also resulted in leaf chlorosis, increased light sensitivity, and dwarfism due to decreased levels of chlorophylls, carotenoids, and gibberellins. In addition, these transgenic plants had reduced levels of sesquiterpene emission, suggesting that the export of isoprenoid intermediates from the plastids into the cytosol was decreased. These results provide genetic evidence that GPPS.SSU modifies the chain length specificity of phylogenetically distant GGPPS and can modulate IPP flux distribution between GPP and GGPP synthesis in planta. 相似文献
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Summary We report here the complete nucleotide sequence of the E. coli triose phosphate isomerase gene. The gene encodes a polypeptide of 255 amino acids which is approximately 46% homologous to eukaryotic triose phosphate isomerases, and approximately 38% homologous to the enzyme from a thermophilic bacterium, Bacillus stearothermophilus. The nucleotide sequence is 55% homologous to that of the corresponding gene in the yeast Saccharomyces cerevisiae. To our knowledge, this is the first report of the sequence of a gene coding a glycolytic enzyme from a prokaryotic organism. 相似文献
616.
Floral fragrance. New inroads into an old commodity. 总被引:2,自引:0,他引:2
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What controls nucleosome positions? 总被引:2,自引:0,他引:2
620.
Eran Pichersky John M. Logsdon J. Mitchell McGrath Robert A. Stasys 《Molecular & general genetics : MGG》1991,225(3):453-458
Summary We have undertaken a systematic search for plastid DNA sequences integrated in the tomato nuclear genome, using heterologous probes taken from intervals of a plastid DNA region spanning 58 kb. A total of two short integrates (202 and 141 nucleotides) were isolated and mapped to chromosomes 9 and 5, respectively. The nucelotide sequence of the integrates and that of the flanking regions were determined. The integration sites contain direct repeat elements similar in position (but not in length or sequence) to the direct repeats previously observed with another plastid integrate in the tomato nuclear genome. Based on these results, a model for the process of movement and integration of plastid sequences into the nuclear genome is discussed. 相似文献