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991.
Recent studies have indicated that the corticotropin releasing hormone (CRF)-related peptide, urocortin, restores key indicators
of damage in animal models for Parkinson’s disease (PD). However, the molecular mechanism for the neuroprotective effect of
urocortin is unknown. 1-Methy-4-phenylpyridinium (MPP+) induces dopaminergic neuronal death. In the present study, MPP+-induced neuroblastoma SH-SY5Y cell death was significantly attenuated by urocortin in a concentration-dependent manner. The
protective effect of urocortin involved the activation of CRF receptor type 1, resulting in the increase of cyclic AMP (cAMP)
levels. Various cAMP-enhancing reagents mimicked the effect of urocortin, while inhibitors for protein kinase A (PKA) blocked
the effect of urocortin, strongly implicating the involvement of cAMP-PKA pathway in the neuroprotective effect of urocortin
on MPP+-induced cell death. As the downstream of this signal pathway, urocortin promoted phosphorylation of both glycogen synthase
kinase 3β and extracellular signal-regulated kinases, which are known to promote cell survival. These neuroprotective signaling
pathways of urocortin may serve as potential therapeutic targets for PD. 相似文献
992.
993.
Kyu‐Tek PARK 《Entomological Science》2012,15(3):294-302
As the eighth part in a series on the family Lecithoceridae (Lepidoptera: Gelechioidea) from New Guinea, Sulciolus Park, gen. nov. of the subfamily Lecithocerinae is described, based on the type species, S. pachystoma (Diakonoff), comb. nov., with two additional new species: (i) S. circulivalvae sp. nov.; and (ii) S. kaindiana sp. nov. The new genus shares with Achroa Meyrick, Onnuria Park, Hamatina Park and Scolizona Park a uniquely specialized 3rd segment of labial palpus, but it is differentiated from them by having a longitudinal furrow on the inner surface of the segment. Sulciolus abrasa (Diakonoff), S. capra (Diakonoff), S. induta (Diakonoff) and S. perspicua (Diakonoff) are newly combined, and Lecithocera sextacta Diakonoff is synonymized with S. perspicua (Diakonoff). Keys to genera related to Lecithocera and to species of the genus are given. Adults, labial palpi, wing venations and male genitalia are illustrated. 相似文献
994.
Seyed Javad Davarpanah Joon-Woo Ahn Suk Min Ko Seo Hee Jung Youn-Il Park Jang Ryol Liu Won Joong Jeong 《Plant biotechnology reports》2012,6(4):305-312
Laccase catalyzes the oxidation of various phenolic compounds that can be used in a wide range of industrial applications such as waste detoxification and the textile industry. In the present study, we generated transplastomic tobacco plants to develop a reliable commercial source of laccase production. The stability of the laccase protein in the transgenic plants was increased by using the enhancer sequence from green fluorescent protein, resulting in three independent lines with high levels of laccase accumulation (up to 2?% of total protein); significant laccase activity, however, was not detected. Interestingly, the transplastomic lines showed slightly retarded vegetative growth, with a light green leaf color in comparison with the control, which may be attributable to copper deficiency induced by ligand chelation by abundantly produced laccase. These results suggest that the tobacco chloroplast is an efficient system for the mass production of laccase protein, but further studies are needed to obtain active enzyme. 相似文献
995.
996.
Suppression of c‐Myc enhances p21WAF1/CIP1‐mediated G1 cell cycle arrest through the modulation of ERK phosphorylation by ascochlorin 下载免费PDF全文
997.
Christine Dominianni Rashmi Sinha James J. Goedert Zhiheng Pei Liying Yang Richard B. Hayes Jiyoung Ahn 《PloS one》2015,10(4)
Increasing evidence suggests that the composition of the human gut microbiome is important in the etiology of human diseases; however, the personal factors that influence the gut microbiome composition are poorly characterized. Animal models point to sex hormone-related differentials in microbiome composition. In this study, we investigated the relationship of sex, body mass index (BMI) and dietary fiber intake with the gut microbiome in 82 humans. We sequenced fecal 16S rRNA genes by 454 FLX technology, then clustered and classified the reads to microbial genomes using the QIIME pipeline. Relationships of sex, BMI, and fiber intake with overall gut microbiome composition and specific taxon abundances were assessed by permutational MANOVA and multivariate logistic regression, respectively. We found that sex was associated with the gut microbiome composition overall (p=0.001). The gut microbiome in women was characterized by a lower abundance of Bacteroidetes (p=0.03). BMI (>25 kg/m2
vs. <25 kg/m2) was associated with the gut microbiome composition overall (p=0.05), and this relationship was strong in women (p=0.03) but not in men (p=0.29). Fiber from beans and from fruits and vegetables were associated, respectively, with greater abundance of Actinobacteria (p=0.006 and false discovery rate adjusted q=0.05) and Clostridia (p=0.009 and false discovery rate adjusted q=0.09). Our findings suggest that sex, BMI, and dietary fiber contribute to shaping the gut microbiome in humans. Better understanding of these relationships may have significant implications for gastrointestinal health and disease prevention. 相似文献
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999.
1000.
Sunyoung Ahn 《Biochemical and biophysical research communications》2010,399(2):256-261
In endothelial cells, X-chromosome linked inhibitor of apoptosis protein (XIAP) regulates cell survival, migration and adhesion. We have recently found that XIAP recruits focal adhesion kinase (FAK) into integrin-associated focal adhesions, controlling cell migration. However, little is understood about the molecular mechanisms by which FAK modulation is controlled by XIAP. In this study, we show that XIAP modulates FAK activity through the control of FAK phosphorylation. In bovine aortic endothelial cells (BAEC), phosphorylation of Tyr-576 in FAK is elevated by laminar shear stress. This elevated phosphorylation appears to be responsible for shear stress-stimulated ERK activation. We found that XIAP knockdown reduces shear stress-enhanced phosphorylation of Tyr-576 and induces shear stress-triggered translocation of FAK into nucleus. Nuclear translocation of FAK reduces contact between FAK and Src, a kinase which phosphorylates Tyr-576. This spatial segregation of FAK from Src decreases Tyr-576 phosphorylation and thus shear-stimulated ERK activation. Taken together, our results demonstrate that XIAP plays a key role in shear stress-stimulated ERK activation by maintaining the Src-accessible location of FAK. 相似文献