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871.
DNA methylation profiling of human chromosomes 6, 20 and 22 总被引:24,自引:0,他引:24
872.
Aggressive behavior is pervasive throughout the animal kingdom, and yet very little is known about its molecular underpinnings. To address this problem, we have developed a population-based selection procedure to increase aggression in Drosophila melanogaster. We measured changes in aggressive behavior in the selected subpopulations with a new two-male arena assay. In only ten generations of selection, the aggressive lines became markedly more aggressive than the neutral lines. After 21 generations, the fighting index increased more than 30-fold. Using microarray analysis, we identified genes with differing expression levels in the aggressive and neutral lines as candidates for this strong behavioral selection response. We tested a small set of these genes through mutant analysis and found that one significantly increased fighting frequency. These results suggest that selection for increases in aggression can be used to molecularly dissect this behavior. 相似文献
873.
Kertész A Váradi G Tóth GK Fajka-Boja R Monostori E Sármay G 《Cellular and molecular life sciences : CMLS》2006,63(22):2682-2693
Phosphopeptides interacting with src homology 2 (SH2) domains can activate essential signaling enzymes in vitro. When delivered to cells, they may disrupt protein-protein interactions, thereby influencing intracellular signaling. We
showed earlier that phosphopeptides corresponding to the inhibitory motif of Fcγ receptor IIb and a motif of the Grb2-associated
binder 1 adaptor protein activate SH2-containing tyrosine phosphatase 2 in vitro. To study the ex vivo effects of these peptides, we have now compared different methods for peptide delivery: (i) permeabilization of the target
cells and (ii) the use of cell-permeable vectors, which are potentially able to transport biologically active compounds into
B cells. We found octanoyl-Arg8 to be an optimal carrier for the delivery of phosphopeptides to the cells. With this strategy, the function of cell-permeable
SHP-2-binding phosphopeptides was analyzed. These peptides modulated the protein phosphorylation in B cells in a dose- and
time-dependent manner.
Received 27 July 2006; received after revision 4 September 2006; accepted 18 September 2006 相似文献
874.
Blasig IE Winkler L Lassowski B Mueller SL Zuleger N Krause E Krause G Gast K Kolbe M Piontek J 《Cellular and molecular life sciences : CMLS》2006,63(4):505-514
Tight junctions seal intercellular clefts via membrane-related strands, hence, maintaining important organ functions. We investigated
the self-association of strand-forming transmembrane tight junction proteins. The regulatory tight junction protein occludin
was differently tagged and cotransfected in eucaryotic cells. These occludins colocalized within the plasma membrane of the
same cell, coprecipitated and exhibited fluorescence resonance energy transfer. Differently tagged strand-forming claudin-5
also colocalized in the plasma membrane of the same cell and showed fluorescence resonance energy transfer. This demonstrates
self-association in intact cells both of occludin and claudin-5 in one plasma membrane. In search of dimerizing regions of
occludin, dimerization of its cytosolic C-terminal coiledcoil domain was identified. In claudin-5, the second extracellular
loop was detected as a dimer. Since the transmembrane junctional adhesion molecule also is known to dimerize, the assumption
that homodimerization of transmembrane tight junction proteins may serve as a common structural feature in tight junction
assembly is supported.
Received 6 October 2005; received after revision 14 December 2005; accepted 27 December 2005
†These authors contributed equally to this work. 相似文献
875.
Glycogen synthase kinase 3β and Alzheimer’s disease: pathophysiological and therapeutic significance 总被引:3,自引:0,他引:3
Balaraman Y Limaye AR Levey AI Srinivasan S 《Cellular and molecular life sciences : CMLS》2006,63(11):1226-1235
Alzheimer’s disease (AD) is a neurodegenerative disorder associated with cognitive and behavioral dysfunction and is the leading
cause of dementia in the elderly. Several studies have implicated molecular and cellular signaling cascades involving the
serine-threonine kinase, glycogen synthase kinase β(GSK-3β) in the pathogenesis of AD. GSK-3β may play an important role in
the formation of neurofibrillary tangles and senile plaques, the two classical pathological hallmarks of AD. In this review,
we discuss the interaction between GSK-3β and several key molecules involved in AD, including the presenilins, amyloid precursor
protein, tau, and β-amyloid. We identify the signal transduction pathways involved in the pathogenesis of AD, including Wnt,
Notch, and the PI3 kinase/Akt pathway. These may be potential therapeutic targets in AD.
Received 19 December 2005; received after revision 24 January 2006; accepted 6 February 2006 相似文献
876.
877.
Relation between total and exchangeable sodium in the body 总被引:1,自引:0,他引:1
878.
Information processing along the course of a visual interneuron. 总被引:1,自引:0,他引:1
Locust ocellar retinal cells are innervated by giant second order cells, 2 mm long, which show discrete zones of integration along their course, including a major zone in the axonal length of the neuron. The complex synaptic arrangements which exist between higher-order afferent and efferent cells and these second order cells along their course suggests that transmission takes place by the electrotonic spread of slow potentials. The size and accessibility of these visual interneurons offers a unique preparation for examining mechanisms of graded synaptic transmission. 相似文献
879.
Early changes of cyclic nucleotide levels in a mitogenic reaction in the rat mesentery. 总被引:2,自引:0,他引:2
By measuring simultaneously cAMP and cGMP we found a biphasic time course with regard to cGMP and the cGMP/cAMP ratio very early in a mitogenic reaction in vivo. This is a new finding. 相似文献
880.