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91.
Altered cortical synaptic morphology and impaired memory consolidation in forebrain- specific dominant-negative PAK transgenic mice 总被引:8,自引:0,他引:8
Hayashi ML Choi SY Rao BS Jung HY Lee HK Zhang D Chattarji S Kirkwood A Tonegawa S 《Neuron》2004,42(5):773-787
Molecular and cellular mechanisms for memory consolidation in the cortex are poorly known. To study the relationships between synaptic structure and function in the cortex and consolidation of long-term memory, we have generated transgenic mice in which catalytic activity of PAK, a critical regulator of actin remodeling, is inhibited in the postnatal forebrain. Cortical neurons in these mice displayed fewer dendritic spines and an increased proportion of larger synapses compared to wild-type controls. These alterations in basal synaptic morphology correlated with enhanced mean synaptic strength and impaired bidirectional synaptic modifiability (enhanced LTP and reduced LTD) in the cortex. By contrast, spine morphology and synaptic plasticity were normal in the hippocampus of these mice. Importantly, these mice exhibited specific deficits in the consolidation phase of hippocampus-dependent memory. Thus, our results provide evidence for critical relationships between synaptic morphology and bidirectional modifiability of synaptic strength in the cortex and consolidation of long-term memory. 相似文献
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93.
Eun Jung Thak Jungho Kim Dong-Jik Lee Jeong Yoon Kim Hyun Ah Kang 《Journal of microbiology (Seoul, Korea)》2018,56(1):11-23
Protein glycosylation, the most universal and diverse post-translational modification, can affect protein secretion, stability, and immunogenicity. The structures of glycans attached to proteins are quite diverse among different organisms and even within yeast species. In yeast, protein glycosylation plays key roles in the quality control of secretory proteins, and particularly in maintaining cell wall integrity. Moreover, in pathogenic yeasts, glycans assembled on cell-surface glycoproteins can mediate their interactions with host cells. Thus, a comprehensive understanding of protein glycosylation in various yeast species and defining glycan structure characteristics can provide useful information for their biotechnological and clinical implications. Yeast-specific glycans are a target for glyco-engineering; implementing human-type glycosylation pathways in yeast can aid the production of recombinant glycoproteins with therapeutic potential. The virulenceassociated glycans of pathogenic yeasts could be exploited as novel targets for antifungal agents. Nowadays, several glycomics techniques facilitate the generation of species-and strain-specific glycome profiles and the delineation of modified glycan structures in mutant and engineered yeast cells. Here, we present the protocols employed in our laboratory to investigate the N-and O-glycan chains released from purified glycoproteins or cell wall mannoproteins in several yeast species. 相似文献
94.
An Appropriate Cutoff Value for Determining the Colonization of Helicobacter pylori by the Pyrosequencing Method: Comparison with Conventional Methods 下载免费PDF全文
95.
SNP frequency, haplotype structure and linkage disequilibrium in elite maize inbred lines 总被引:3,自引:0,他引:3
Ada Ching Katherine S Caldwell Mark Jung Maurine Dolan Oscar S Smith Scott Tingey Michele Morgante Antoni J Rafalski 《BMC genetics》2002,3(1):19-14
Background
Recent studies of ancestral maize populations indicate that linkage disequilibrium tends to dissipate rapidly, sometimes within 100 bp. We set out to examine the linkage disequilibrium and diversity in maize elite inbred lines, which have been subject to population bottlenecks and intense selection by breeders. Such population events are expected to increase the amount of linkage disequilibrium, but reduce diversity. The results of this study will inform the design of genetic association studies. 相似文献96.
Il-Chan Kim Young Ja Kim Young-Mi Lee Bok-Geon Kim Tae-Jin Park Hyeung-Sin Kim Min-Min Jung Tim D Williams Wonchoel Lee Jae-Seong Lee 《DNA sequence》2004,15(2):159-163
We synthesized a cDNA library from the intertidal copepod Tigriopus japonicus, converted it to phagemids and sequenced expressed sequence tags (ESTs). Of these, Tigriopus translationally controlled tumor protein/histamine releasing factor (TCTP/HRF) was further characterized. The Tigriopus TCTP/HRF gene encoded 172 amino acid residues and showed high similarity to Drosophila but moderate similarity to other annelids (e.g. Brugia, Wuchereria and C. elegans). The Tigriopus TCTP/HRF gene appeared in the same clade as the annelids. Here, we describe the analysis of the Tigriopus TCTP/HRF gene. 相似文献
97.
Proteome profiling of the inclusion body (IB) fraction of recombinant proteins produced in Escherichia coli suggested that two small heat shock proteins, IbpA and IbpB, are the major proteins associated with IBs. In this study, we demonstrate that IbpA and IbpB facilitate the production of recombinant proteins in E. coli and play important roles in protecting recombinant proteins from degradation by cytoplasmic proteases. We examined the cytosolic production, and Tat- or Sec-dependent secretion of the enhanced green fluorescent protein (EGFP) in wild type, ibpAB(-) mutant, and ibpAB-amplified E. coli strains. Analysis of fluorescence histograms and confocal microscopic imaging revealed that over-expression of the ibpA and/or ibpB genes enhanced cytosolic EGFP production whereas knocking out the ibpAB genes enhanced secretory production. This strategy seems to be generally applicable as it was successfully employed for the enhanced cytosolic or secretory production of several other recombinant proteins in E. coli. 相似文献
98.
MicroRNA biogenesis and function in higher plants 总被引:1,自引:0,他引:1
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