Shigeyuki Magi

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In neurons, as in other excitable cells, mitochondria extrude Ca(2+) ions from their matrix in exchange with cytosolic Na(+) ions. This exchange is mediated by a specific transporter located in the inner mitochondrial membrane, the mitochondrial Na(+)/Ca(2+) exchanger (NCX(mito)). The stoichiometry of NCX(mito)-operated Na(+)/Ca(2+) exchange has been the(More)
Analysis of the connexin32 gene in patients with X-linked Charcot-Marie-Tooth disease shows mutations distributed throughout the molecule, with all domains affected except the fourth transmembrane domain and the distal carboxy terminus. Sequence analysis of DNA from 19 unrelated patients detected six novel mutations and three previously reported mutations.(More)
Cell migration is an essential step for tumor metastasis. The small GTPase Rac1 plays an important role in cell migration. Previously, we reported that epidermal growth factor (EGF) induced two waves of Rac1 activation; namely, at 5 min and 12 h after stimulation. A second wave of EGF-induced Rac1 activation was required for EGF-induced cell migration,(More)
Extracellular signal-regulated kinase (ERK) plays a central role in signal transduction networks and cell fate decisions. Sustained ERK activation induces cell differentiation, whereas transient ERK results in the proliferation of several types of cells. Sustained ERK activity stabilizes the proteins of early-response gene products. However, the effect of(More)
The aim of this study was to analyze the diversity and consistency of regulatory signaling in cancer cell migration, using a chemical genomic approach. The effects of 34 small molecular compounds were assessed quantitatively by wound healing assay in ten types of migrating cells. Hierarchical clustering was performed on the subsequent migration inhibition(More)
The immediate-early response mediates cell fate in response to a variety of extracellular stimuli and is dysregulated in many cancers. However, the specificity of the response across stimuli and cell types, and the roles of non-coding RNAs are not well understood. Using a large collection of densely-sampled time series expression data we have examined the(More)
The analysis of CAGE (Cap Analysis of Gene Expression) time-course has been proposed by the FANTOM5 Consortium to extend the understanding of the sequence of events facilitating cell state transition at the level of promoter regulation. To identify the most prominent transcriptional regulations induced by growth factors in human breast cancer, we apply here(More)
To explore the diversity and consistency of the signaling pathways that regulate tumor cell migration, we chose three human tumor cell lines that migrated after treatment with EGF. We then quantified the effect of fifteen inhibitors on the levels of expression or the phosphorylation levels of nine proteins that were induced by EGF stimulation in each of(More)
The ErbB receptor signaling pathway plays an important role in the regulation of cellular proliferation, survival and differentiation, and dysregulation of the pathway is linked to various types of human cancer. Mathematical models have been developed as a practical complementary approach to deciphering the complexity of ErbB receptor signaling and(More)
In the course of screening for an inhibitor of farnesyl transferase (FTase), we identified two compounds, N-benzyl-aclacinomycin A (ACM) and N-allyl-ACM, which are new derivatives of ACM. N-benzyl-ACM and N-allyl-ACM inhibited FTase activity with IC50 values of 0.86 and 2.93 μM, respectively. Not only ACM but also C-10 epimers of each ACM derivative failed(More)