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71.
A novel Arabidopsis thaliana mutant of one member of the pentatricopeptide repeat (PPR) gene family has been identified among T-DNA insertion lines. Tagging
of the At1g53330 gene caused the appearance of a semi-lethal mutation with a complex phenotypic expression from embryo lethality
associated with the abnormal pattern of cell division during globular to heart transition to fertile plants with just subtle
phenotypic changes. The PPR protein At1g53330.1 was predicted to be targeted to mitochondria by TargetP and MitoProt programs.
Complementation analysis confirmed that the phenotype is a result of a single T-DNA integration. A thorough functional analysis
of this mutant aimed at finding a particular organelle target of At1g53330.1 protein will follow. 相似文献
72.
A. A. Egorshina R. M. Khairullin A. R. Sakhabutdinova M. A. Luk’yantsev 《Russian Journal of Plant Physiology》2012,59(1):134-140
Wheat (Triticum aestivum L., cv. Kazakhstanskaya 10) seedling growth activation by the endophytic 11BM strain of the bacterium Bacillus subtilis Cohn and the involvement of phytohormones in this process were studied. At the concentration used, bacteria enhanced wheat
root and shoot growth as compared to control. Biotests demonstrated auxin-, cytokinin-, and gibberellin-like activities of
the endophyte, but the result depended on the way of experiment performing. When wheat seeds were treated with the spores
of B. subtilis 11BM strain, the concentrations of IAA and ABA increased transiently in the roots and shoots of the seedlings. The involvement
of IAA oxidase in the plant response to inoculation with bacteria was shown; it was accompanied by a decrease in enzyme activity,
which occurred later than auxin accumulation. It was concluded that observed changes in the hormonal status of wheat plants
under the influence of the endophytic bacterial strain may be one of the mechanisms for seedling growth stimulation. 相似文献
73.
Shi SY Martin RG Duncan RE Choi D Lu SY Schroer SA Cai EP Luk CT Hopperton KE Domenichiello AF Tang C Naples M Dekker MJ Giacca A Adeli K Wagner KU Bazinet RP Woo M 《The Journal of biological chemistry》2012,287(13):10277-10288
Non-alcoholic fatty liver disease (NAFLD) is becoming the leading cause of chronic liver disease and is now considered to be the hepatic manifestation of the metabolic syndrome. However, the role of steatosis per se and the precise factors required in the progression to steatohepatitis or insulin resistance remain elusive. The JAK-STAT pathway is critical in mediating signaling of a wide variety of cytokines and growth factors. Mice with hepatocyte-specific deletion of Janus kinase 2 (L-JAK2 KO mice) develop spontaneous steatosis as early as 2 weeks of age. In this study, we investigated the metabolic consequences of jak2 deletion in response to diet-induced metabolic stress. To our surprise, despite the profound hepatosteatosis, deletion of hepatic jak2 did not sensitize the liver to accelerated inflammatory injury on a prolonged high fat diet (HFD). This was accompanied by complete protection against HFD-induced whole-body insulin resistance and glucose intolerance. Improved glucose-stimulated insulin secretion and an increase in β-cell mass were also present in these mice. Moreover, L-JAK2 KO mice had progressively reduced adiposity in association with blunted hepatic growth hormone signaling. These mice also exhibited increased resting energy expenditure on both chow and high fat diet. In conclusion, our findings indicate a key role of hepatic JAK2 in metabolism such that its absence completely arrests steatohepatitis development and confers protection against diet-induced systemic insulin resistance and glucose intolerance. 相似文献
74.
We isolated and amplified by PCR 16S rDNA from bacteria attached to the bovine rumen wall and analyzed it by denaturing gradient
gel electrophoresis (DGGE) with subsequent sequence analysis. The attached bacterial community differed from the bacteria
of rumen content; however, no differences were observed among the five epithelial sampling sites taken from each animal. The
DGGE profile of the bacterial population attached to the rumen wall represented a high inter-animal variation. 相似文献
75.
Auto anti-A1 and auto anti-NA1 after bone marrow transplantation 总被引:1,自引:0,他引:1
P Herzog P Korínková M Stambergová M Lukásová 《Folia haematologica (Leipzig, Germany : 1928)》1987,114(6):874-880
The production of auto anti-A1 and auto anti-NA1 antibodies in patient with aplastic anemia has been described. The patient of group A1 received bone marrow from his brother of group A2. For immunosuppression cyclosporine A was administered. 相似文献
76.
O. V. Zaitseva I. P. Ivanova E. L. Luk’yanova 《Journal of Evolutionary Biochemistry and Physiology》2000,36(4):421-431
Ultrastructure of the main neural elements in the cell body area of procerebrums, the higher olfactory centers of terrestrial
snails and slugs, was studied. It has been shown that nearly every neuron of the procerebrums contains several types of agranular
and granular vesicles used in various interneuronal connections. Several types of classic and non-classic synaptic junctions
between granular cell bodies and their main processes as well as between granular cells and various neural fibers coming to
this area from other brain regions are described. About 70% of the synapses and synaptic-like junctions are symmetric. Complex
synaptic complexes of both divergent and convergent types are observed. It has been established that the coming fibers form
numerous, spatially separated, parallel, divergent and partially overlapping, synaptic complexes with the procerebrum neurons
clustered in columns. Due to the high degree of convergence of afferent inputs in the procerebrums and the huge amount of
symmetric and unidirectional links, procerebrums may represent an integral, highly differentiated, integrative system of the
molluscan brain. 相似文献
77.
78.
79.
The maximum entropy method, originally developed for astronomical image restoration, has already been successfully applied to a variety of biophysical problems. Through numerical inverse Laplace transformation, the method determines the lifetime distribution function with the largest informational entropy. Starting from a flat distribution, it results in the consistent selection of a single distribution from the numerous possible ones that correctly fit the data. In this paper, we discuss the application of the method to kinetic processes that have both rise and decay components, and test the algorithm with different signal to noise ratio generated data. It is proved that the mass conservation constraint can be taken into account by reducing the search to a lower dimensional subspace. The effect of noise on the width of lifetime distribution is studied and it is shown that an inherent entropy connected to the underlying kinetics can be separated from the noise generated entropy. The possibility of the application of the method to the photocycle kinetics of bacteriorhodopsin is also shown. 相似文献
80.
Pitx3 is required for motor activity and for survival of a subset of midbrain dopaminergic neurons 总被引:11,自引:0,他引:11
van den Munckhof P Luk KC Ste-Marie L Montgomery J Blanchet PJ Sadikot AF Drouin J 《Development (Cambridge, England)》2003,130(11):2535-2542
Mesencephalic dopaminergic (MesDA) neurons play crucial roles in motor and behavioral processes; their loss in Parkinson's disease (PD) results in striatal dopamine (DA) deficiency and hypokinetic movement disorder. The Pitx3 homeobox gene is expressed in the MesDA system. We now show that only a subset of MesDA neurons express Pitx3 and that in Pitx3-deficient aphakia mice, this subset is progressively lost by apoptosis during fetal (substantia nigra, SN) and postnatal (ventral tegmental area) development, resulting in very low striatal DA and akinesia. Similar to human PD, dorsal SN neurons (which are Pitx3 negative) are spared in mutant mice. Thus, Pitx3 defines a pathway for survival of neurons that are implicated in PD and that are required for spontaneous locomotor activity. 相似文献