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941.
Guo Li Xiao‐ai Zhang Hua Wang Xin Wang Chun‐ling Meng Chu‐yan Chan David Tai Wai Yew Kam Sze Tsang Karen Li Sau‐na Tsai Sai‐ming Ngai Zhong Chao Han Marie Chia‐mi Lin Ming‐liang He Hsiang‐fu Kung Professor 《Proteomics》2009,9(1):20-30
Umbilical cord (UC) and placenta (P) have been suggested as alternatives to bone marrow (BM) as sources of mesenchymal stem cells (MSC) for cell therapy, with both UC‐ and P‐MSC possess immunophenotypic and functional characteristics similar to BM‐MSC. However, their migration capacity, which is indispensable during tissue regeneration process, is unclear. Under defined conditions, the migration capacity of BM‐ and P‐MSC was found 5.9‐ and 3.2‐folds higher than that of UC‐MSC, respectively. By the use of 2‐DE and combined MS and MS/MS analysis, six differentially expressed proteins were identified among these MSC samples, with five of them known to be involved in cell migration as migration enhancing or inhibiting proteins. Consistent with their migration capacity, the levels of migration enhancing proteins including cathepsin B, cathepsin D and prohibitin,were significantly lower in UC‐MSC when compared with those in BM‐ and P‐MSC. For the migration inhibiting proteins such as plasminogen activator inhibitor‐1 (PAI‐1) and manganese superoxide dismutase, higher expression was found in the UC‐MSC. We also showed that the overexpression of the PAI‐1 impaired the migration capacity of BM‐ and P‐MSC while silencing of PAI‐1 enhanced the migration capacity of UC‐MSC. Our study indicates that PAI‐1 and other migration‐related proteins are pivotal in governing the migration capacity of MSC. 相似文献
942.
943.
944.
Tao Wang Kang Shao Qinying Chu Yanfei Ren Yiming Mu Lijia Qu Jie He Changwen Jin Bin Xia 《BMC bioinformatics》2009,10(1):83
Background
Spectral processing and post-experimental data analysis are the major tasks in NMR-based metabonomics studies. While there are commercial and free licensed software tools available to assist these tasks, researchers usually have to use multiple software packages for their studies because software packages generally focus on specific tasks. It would be beneficial to have a highly integrated platform, in which these tasks can be completed within one package. Moreover, with open source architecture, newly proposed algorithms or methods for spectral processing and data analysis can be implemented much more easily and accessed freely by the public. 相似文献945.
Background
Numerous proteins can be converted to amyloid-like fibrils to increase cytotoxicity and induce apoptosis, but the methods generally require a high concentration of protein, vigorous shaking, or fibril seed. As well, the detailed mechanism of the cytotoxic effects is not well characterized. In this study, we have developed a novel process to convert native proteins into the fibrillar form. We used globular bovine serum albumin (BSA) as a model protein to verify the properties of the fibrillar protein, investigated its cellular effects and studied the signaling cascade induced by the fibrillar protein. 相似文献946.
947.
Mitochondrial kinases in Parkinson’s disease: Converging insights from neurotoxin and genetic models
Alterations in mitochondrial biology have long been implicated in neurotoxin, and more recently, genetic models of parkinsonian neurodegeneration. In particular, kinase regulation of mitochondrial dynamics and turnover are emerging as central mechanisms at the convergence of neurotoxin, environmental and genetic approaches to studying Parkinson’s disease (PD). Kinases that localize to mitochondria during neuronal injury include mitogen activated protein kinases (MAPK) such as extracellular signal regulated protein kinases (ERK) and c-Jun N-terminal kinases (JNK), protein kinase B/Akt, and PTEN-induced kinase 1 (PINK1). Although site(s) of action within mitochondria and specific kinase targets are still unclear, these signaling pathways regulate mitochondrial respiration, transport, fission–fusion, calcium buffering, reactive oxygen species (ROS) production, mitochondrial autophagy and apoptotic cell death. In this review, we summarize accelerating experimental evidence gathered over the last decade that implicate a central role for kinase signaling at the mitochondrion in Parkinson’s and related neurodegenerative disorders. Interactions involving α-synuclein, leucine rich repeat kinase 2 (LRRK2), DJ-1 and Parkin are discussed. Converging mechanisms from different model systems support the concept of common pathways in parkinsonian neurodegeneration that may be amenable to future therapeutic interventions. 相似文献
948.
949.
C.-G. Chu S. Chao T. L. Friesen J. D. Faris S. Zhong S. S. Xu 《Molecular breeding : new strategies in plant improvement》2010,25(2):327-338
Durum wheat (Triticum turgidum L. subsp. durum, 2n = 4x = 28, AABB) is an important cereal used for making pasta products. Compared with bread wheat, durum wheat receives less attention
in genetic and genomic studies. In this research, a tetraploid wheat doubled haploid (DH) population derived from the cross
between the durum wheat cultivar ‘Lebsock’ and the T. turgidum subsp. carthlicum (2n = 4x = 28, AABB) accession PI 94749 was developed. The population consisted of 146 lines and was used to construct linkage maps
of all 14 chromosomes. The maps consisted of 280 SSR markers and spanned 2,034.1 cM with an average density of one marker
per 7.2 cM. The DH population and the whole genome linkage maps were then used to identify QTLs associated with tan spot resistance.
The DH population was inoculated separately with two Ptr ToxA-producing isolates (Pti2 and 86-124) representing races 1 and
2, respectively, of Pyrenophora tritici-repentis, and five resistance QTLs were detected on chromosome arms 3AS, 3BL, 5AL and 7BL. Together, the QTLs explained a total of
46 and 41% of the phenotypic variation for reaction to Pti2 and 86-124, respectively. The Tsn1-Ptr ToxA interaction was not a significant factor in tan spot development in this population, and none of the QTLs corresponded
to previously identified loci known to confer insensitivity to host-selective toxins (HSTs) produced by P. tritici-repentis. This result, together with those of other similar studies, indicates that the wheat–P. tritici-repentis pathosystem involves more factors than currently published host-toxin interactions. The DH population and genetic maps reported
here will be useful for genetic dissection of important agronomic traits as well as the identification and development of
markers for marker-assisted selection (MAS). 相似文献
950.
J. Xu R. Michalet J.‐L. Zhang G. Wang C.‐J. Chu S. Xiao 《Plant biology (Stuttgart, Germany)》2010,12(5):780-787
Biotic interaction studies have revealed a large discrepancy among experiments in target responses to the effects of neighbours, which may in part be due to both high species‐specificity of plant responses and low number of target species used in experiments. Our aim was to assess facilitative responses at the community level and the role of both functional groups and ecological attributes of target species. In a sub‐alpine grassland on the eastern Tibet plateau, we assessed growth responses of all species in the community to removal of a dominant shrub. We also measured changes in the main environmental variables. Species responses were analysed by functional group and in relation to their mean regional altitudinal distribution. All significant interactions were positive and affected one‐third of the total species richness of the community. All functional groups were facilitated but forbs were less strongly facilitated than in the two other groups. High‐alpine species were less strongly facilitated than low‐sub‐alpine species, but the strength of this relationship was weaker than that reported in previous work. There was evidence of a decrease in extreme temperatures below the canopy of the shrub but no variations in soil moisture. We conclude that the highly stressful conditions induced by the dry continental climate of the eastern Tibet plateau are a main driver of the exclusive dominance of positive interactions. Assessing interactive responses at the community level is likely to provide a useful tool to better understand the role of biotic interactions in community responses to environmental changes. 相似文献