Tatsuo Furuyama

Osaka City University, Ōsaka, Ōsaka, Japan

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Publications (60)138.78 Total impact

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    ABSTRACT: Cerebral ischemia evokes neuroinflammatory response. Inflammatory stimulation induces microglial activation, such as changes of their morphology from ramified to ameboid, expression of iNOS and cytokines, and the elevation of proliferative activity. Activated microglia play important roles in pathogenesis of cerebral ischemia. A previous study indicated that Sema4D promoted iNOS expression in cultured microglia; however, roles of Sema4D on microglial activation in ischemic injury remains unclear. We investigated the effect of Sema4D-deficiency on microglial activation by using permanent middle cerebral artery occlusion (MCAO) in mice. In this study, ischemia-induced activated microglia were classified into activated-ramified microglia and ameboid microglia based on their morphology. We demonstrated that the rate of iNOS expression in activated-ramified microglia was lower than that in ameboid microglia, while the most proliferating microglia were activated-ramified microglia but not ameboid microglia after cerebral ischemia. Sema4D-deficiency decreased the number of ameboid microglia and iNOS-expressing activated-ramified microglia in the peri-ischemic cortex. These changes by Sema4D-deficiency contributed to the reduction of NO production that was estimated by nitrite concentration in ischemic cortex. On the other hand, Sema4D-deficiency promoted proliferation of microglia in the peri-ischemic cortex. Importantly, ischemia-induced apoptosis and postischemic behavioral abnormality were moderated in Sema4D(-/-) mice. These findings suggest that Sema4D promotes cytotoxic activation of microglia and inhibits functional recovery after cerebral ischemia. GLIA 2015. © 2015 Wiley Periodicals, Inc.
    Glia 07/2015; DOI:10.1002/glia.22890 · 6.03 Impact Factor
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    ABSTRACT: Several reports have suggested that Foxo1, a key regulator in differentiation, growth and metabolism, is involved in pancreatic β-cell function. However, detailed analyses have been hampered by a lack of Foxo1-deficient β cells. To elucidate Foxo1's function in β cells, we produced a β-cell line with inducible Foxo1 deletion. We generated a conditional knockout mouse line, in which Cre recombinase deletes the Foxo1 gene. We then established a β-cell line from an insulinoma induced in this knockout mouse by the β-cell-specific expression of simian virus 40 T antigen. In this cell line, designated MIN6-Foxo1flox/flox, adenovirus-mediated Cre expression ablates the Foxo1 gene, generating MIN6-Foxo1-KO cells. Using these knockout and floxed cell lines, we found that Foxo1 ablation enhanced the glucose-stimulated insulin secretion (GSIS) at high glucose concentrations and enhanced β-cell proliferation. We also conducted DNA microarray analyses of MIN6-Foxo1-KO cells infected with either an adenovirus vector expressing a constitutively active FOXO1 or a control vector and identified several Foxo1-regulated genes, including some known to be related to β-cell function. These cells should be useful for further studies on Foxo1's roles in β-cells and may lead to novel strategies for treating the impaired insulin secretion in type 2 diabetes mellitus.
    Genes to Cells 07/2012; 17(9):758-67. DOI:10.1111/j.1365-2443.2012.01625.x · 2.81 Impact Factor
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    ABSTRACT: The specific functions of intrinsic regulators of OL differentiation are poorly understood. Sema4D, originally found as a negative regulator of axon guidance, is mainly expressed by oligodendrocytes in the postnatal brain, and our previous study revealed that the lack of Sema4D induced an increase in the number of oligodendrocytes in the cerebral cortex, suggesting that Sema4D may function as an intrinsic regulator of oligodendrocyte development. In this study, we assessed the effects of Sema4D deficiency and of the exogenous addition of Sema4D on oligodendrocyte differentiation. Sema4D deficiency induced an increase in the number of oligodendrocytes in the cerebral cortex at postnatal day 14 and later, without increase in the number of oligodendrocyte progenitor cells. This increase was also observed in cultured oligodendrocytes obtained from Sema4D-deficient mice. Then we investigated whether Sema4D deficiency can increase the proliferation of the progenitor cells or influence the apoptosis. Apoptotic oligodendrocytes were markedly reduced in number in the developing cerebral cortex and in cultured oligodendrocytes obtained from Sema4D-deficient mice, although no significant change was found in proliferation of oligodendrocyte progenitor cells. Exogenous addition of Sema4D prevented the oligodendrocytes from this reduction of apoptosis, and further enhanced apoptosis in oligodendrocytes. Thus, Sema4D may act as an intrinsic inhibitory regulator of oligodendrocyte differentiation by promoting apoptosis.
    Molecular and Cellular Neuroscience 12/2011; 49(3):290-9. DOI:10.1016/j.mcn.2011.12.004 · 3.84 Impact Factor
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    ABSTRACT: The FoxO transcription factors may be involved in the antiaging effect of calorie restriction (CR) in mammals. To test the hypothesis, we used FoxO1 knockout heterozygotic (HT) mice, in which the FoxO1 mRNA level was reduced by 50%, or less, of that in wild-type (WT) mouse tissues. The WT and HT mice were fed ad libitum (AL) or 30% CR diets from 12 weeks of age. Aging- and CR-related changes in body weight, food intake, blood glucose, and insulin concentrations were similar between the WT and HT mice in the lifespan study. The response to oxidative stress, induced by intraperitoneal injection of 3-nitropropionic acid (3-NPA), was evaluated in the liver and hippocampus at 6 months of age. Several of the selected FoxO1-target genes for cell cycle arrest, DNA repair, apoptosis, and stress resistance were up-regulated in the WT-CR tissues after 3-NPA injection, while the effect was mostly diminished in the HT-CR tissues. Of these gene products, we focused on the nuclear p21 protein level in the liver and confirmed its up-regulation only in the WT-CR mice in response to oxidative stress. The lifespan did not differ significantly between the WT and HT mice in AL or CR conditions. However, the antineoplastic effect of CR, as indicated by reduced incidence of tumors at death in the WT-CR mice, was mostly abrogated in the HT-CR mice. The present results suggest a role for FoxO1 in the antineoplastic effect of CR through the induction of genes responsible for protection against oxidative and genotoxic stress.
    Aging cell 03/2010; 9(3):372-82. DOI:10.1111/j.1474-9726.2010.00563.x · 6.34 Impact Factor
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    ABSTRACT: Semaphorins, a family of secreted and membrane-bound proteins, are known to function as repulsive axon guidance molecules. Sema4D, a class 4 transmembrane-type semaphorin, is expressed by oligodendrocytes in the central nervous system, but its role is unknown. In this study, the effects of Sema4D deficiency on oligodendrocytes were studied in intact and ischemic brains of adult mice. As observed in previous studies, Sema4D marked by beta-galactosidase in Sema4D mutant mice was localized exclusively on myelin-associated glycoprotein (MAG)-positive oligodendrocytes but not on NG2-positive oligodendrocyte progenitor cells (OPCs). Although there was no difference in the number of the latter cells between Sema4D-deficient and wild-type mice, the number of MAG-positive cells was significantly increased in the cerebral cortex of both nonischemic and postischemic brains of Sema4D-deficient mice. Cell proliferation, observed by using bromodeoxyuridine incorporation, was evident in the MAG-positive cells that developed after cerebral ischemia. These data indicate that Sema4D is involved in oligodendrogenesis during development and during recovery from ischemic injury.
    Journal of Neuroscience Research 10/2009; 87(13):2833-41. DOI:10.1002/jnr.22124 · 2.59 Impact Factor
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    ABSTRACT: The forkhead transcription factors regulate the correct organization of vascular system. One of them, Foxo1 is an important physiological regulator of endothelial cell morphology in response to VEGF, while underlying mechanisms are largely unknown. In order to elucidate the cellular function of Foxo1, we used a three-dimensional culture system for the differentiation of Flk1-expressing mesodermal precursor cells derived from ES cells to cord forming endothelial cells and associating vascular smooth muscle cells. While Foxo1(+/+) endothelial cells organized into long vessel-like structures associated with smooth muscle cells, Foxo1(-/-) endothelial cells could form only short sprouts. Foxo1(-/-) endothelial cells have punctate accumulation of filamentous actin, thick circumferential bundles of microtubules with small spikes at the tip of cells, and no interaction with smooth muscle cells. Our results suggest the involvement of Foxo1 in cytoskeletal remodeling of endothelial cells and recruitment of smooth muscle cells during vascular development.
    Biochemical and Biophysical Research Communications 10/2009; 390(3):861-6. DOI:10.1016/j.bbrc.2009.10.063 · 2.30 Impact Factor
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    ABSTRACT: Foxo1, a member of the Foxo subfamily of forkhead box transcription factors, is known to be essential for progression of normal vascular development in the mouse embryos. In the cultures of endothelial cells derived from embryonic stem cells, Foxo1-deficient endothelial cells exhibit an abnormal morphological response to vascular endothelial growth factor-A (VEGF-A), which is characterized by a lack of cell elongation, yet the molecular mechanisms governing endothelial cell morphology under angiogenic stimulation remain unknown. Here, we report that transforming growth actor-beta also induces endothelial cell elongation in collaboration with Foxo1 and VEGF-A. Furthermore, tetracycline-regulated induction of Foxo3, another member of the Foxo subfamily, into Foxo1-null endothelial cells failed to restore abnormal morphological response to VEGF-A at an early differentiation stage. In contrast, Foxo1 and Foxo3 exerted the same function at a late differentiation stage, i.e. enhancement of VEGF responsiveness and promotion of cell elongation. Our results provide evidence that endothelial cell morphology is regulated by several mechanisms in which Foxo1 and Foxo3 express distinct functional properties depending on differentiation stages.
    Genes to Cells 10/2009; 14(10):1167-81. DOI:10.1111/j.1365-2443.2009.01343.x · 2.81 Impact Factor
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    ABSTRACT: We studied the effects of selective loss of capsaicin-sensitive primary sensory neurons on thermosensation and thermoregulation in rats. Neonatal capsaicin treatment in rats caused a remarkable decrease in the number of small-diameter neurons in the dorsal root ganglion (DRG) compared with their number in the control rats. Gene expression analysis for various thermo-sensitive transient receptor potential (TRP) channels indicated marked reductions in the mRNA levels of TRPV1 (70%), TRPM8 (46%) and TRPA1 (64%), but not of TRPV2, in the DRG of capsaicin-treated rats compared with those in the control rats. In addition to the heat and cold insensitivity, capsaicin-treated rats showed lower rectal core temperature, higher skin temperature and decreased sensitivity to ambient temperature alteration under normal housing at room temperature, suggesting impaired thermosensation and change in thermoregulation in the rats. Uncoupling protein 1 (UCP1) expression and the thermogenic ability in brown adipose tissues were attenuated in the capsaicin-treated rats. These results indicate a critical role of capsaicin-sensitive sensory neurons in both heat and cool sensation and hence in basal thermal homeostasis, which is balanced by heat release and production including UCP1 thermogenesis, following sensation of the ambient temperature.
    Journal of Biochemistry 04/2008; 143(3):385-93. DOI:10.1093/jb/mvm233 · 2.58 Impact Factor
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    ABSTRACT: Semaphorins are a group of secreted and membrane-associated molecules that play important roles in axon navigation. Several semaphorin family molecules are expressed in the pharyngeal arches and tooth germs. We analysed the expression of membrane-associated Semaphorin 4D (Sema4D) in tooth germs, and examined its potential role in regulating the differentiation of rat incisor pulp-derived cells in vitro. mRNA expression was examined by in situ hybridisation. The effects of Sema4D on rat pulp-derived cells were examined by adenovirus-mediated overexpression in vitro. Both epithelial and mesenchymal cells of tooth germs expressed Sema4D at the early bell stage. Later, the odontoblasts predominantly expressed Sema4D, while the epithelial expression greatly decreased. The overexpression of Sema4D in rat incisor pulp-derived cells strongly inhibited mineralisation. This inhibition was preceded by a reduction of collagen fibre production at the level of mRNA synthesis. These results indicate that Sema4D is expressed in both epithelial and mesenchymal cells of the tooth germs. Sema4D represses collagen synthesis of pulp-derived cells, indicating it might negatively regulate odontoblast differentiation.
    Archives of Oral Biology 02/2008; 53(1):27-34. DOI:10.1016/j.archoralbio.2007.08.005 · 1.74 Impact Factor
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    ABSTRACT: Plexin-B1, Sema4D receptor, mediates retraction and extension signals in axon guidance by associating with PDZ-containing Rho guanine nucleotide exchange factors (PDZ-RhoGEFs) which can activate a small Rho GTPase RhoA. RhoA is implicated in spine formation by rearranging actin cytoskeleton. Exogenous application of Sema4D to cultured neurons caused activation of RhoA, increase of spine density and changes in spine shape. Sema4D-induced changes in spine density were blocked by either Rho-kinase (a downstream of RhoA, ROCK) inhibitor Y-27632 or by overexpression of plexin-B1 mutant lacking the C-terminus which no longer associates with PDZ-RhoGEFs. This study suggests that Sema4D-plexin-B1 play a crucial role in spine formation by regulating RhoA/ROCK pathway.
    Neuroscience Letters 12/2007; 428(1):1-6. DOI:10.1016/j.neulet.2007.09.045 · 2.03 Impact Factor
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    ABSTRACT: Several semaphorins are thought to function as potent inhibitors of axonal growth. We have found that Sema4D stimulates axonal outgrowth of embryonic dorsal root ganglion (DRG) neurones in stead of retraction. Neutralizing antibodies to Sema4D inhibit this action. This action appears to differ slightly from that on PC12 cells, because DRG neurones respond to Sema4D without addition of nerve growth factor (NGF), while PC12 cells do not. On the other hand, it is blocked by deprivation of endogenous NGF with antibodies to NGF and also by Trk-inhibitor K252a, suggesting that endogenously produced-NGF and the activation of Trk receptor are required for Sema4D-action on DRG neurones. These indicate that neurite-outgrowth promoting actions of Sema4D are similar between DRG neurones and PC12 cells, since NGF-Trk signalling are required for these actions. Since Schwann cells can produce NGF, the contamination of these cells in our DRG culture might explain this action. In addition to plexin-B1 that is known as a Sema4D receptor, binding experiments indicate plexin-B2 as another receptor candidate for Sema4D. These plexins and Sema4D are expressed in embryonic DRGs. We suggest a new function of Sema4D as a neurite-outgrowth stimulating, autocrine/paracrine factor in embryonic sensory neurones.
    Genes to Cells 10/2004; 9(9):821-9. DOI:10.1111/j.1365-2443.2004.00766.x · 2.81 Impact Factor
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    ABSTRACT: Members of the Foxo family, Foxo1 (Fkhr), Foxo3 (Fkhrl1), and Foxo4 (Afx), are mammalian homologs of daf-16, which influences life span and energy metabolism in Caenorhabditis elegans. Mammalian FOXO proteins also play important roles in cell cycle arrest, apoptosis, stress resistance, and energy metabolism. In this study, we generated Foxo1-deficient mice to investigate the physiological role of FOXO1. The Foxo1-deficient mice died around embryonic day 11 because of defects in the branchial arches and remarkably impaired vascular development of embryos and yolk sacs. In vitro differentiation of embryonic stem cells demonstrated that endothelial cells derived from wild-type and Foxo1-deficient embryonic stem cells were able to produce comparable numbers of colonies supported by a layer of OP9 stromal cells. Although the morphology of the endothelial cell colonies was identical in both genotypes in the absence of exogenous vascular endothelial growth factor (VEGF), Foxo1-deficient endothelial cells showed a markedly different morphological response compared with wild-type endothelial cells in the presence of exogenous VEGF. These results suggest that Foxo1 is essential to the ability of endothelial cells to respond properly to a high dose of VEGF, thereby playing a critical role in normal vascular development.
    Journal of Biological Chemistry 09/2004; 279(33):34741-9. DOI:10.1074/jbc.M314214200 · 4.57 Impact Factor
  • Nozomi Mori · Tatsuo Furuyama · Hitoshi Yamashita
    Nippon Ronen Igakkai Zasshi Japanese Journal of Geriatrics 12/2003; 40(6):578-81.
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    Tatsuo Furuyama · Kazuko Kitayama · Hitoshi Yamashita · Nozomu Mori
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    ABSTRACT: A forkhead-type transcription factor, DAF-16, is located in the most downstream part of the insulin signalling pathway via PI3K (phosphoinositide 3-kinase). It is essential for the extension of life-span and is also involved in dauer formation induced by food deprivation in Caenorhabditis elegans. In the present study, we addressed whether or not FOXO members AFX, FKHR (forkhead homologue in rhabdomyosarcoma) and FKHRL1 (FKHR-like protein 1), mammalian counterparts of DAF-16, are involved in starvation stress. We found a remarkable selective induction of FKHR and FKHRL1 transcripts in skeletal muscle of mice during starvation. The induction of FKHR gene expression was observed at 6 h after food deprivation, peaked at 12 h, and returned to the basal level by 24 h of refeeding. The induction was also found in skeletal muscle of mice with glucocorticoid treatment. Moreover, we found that the levels of PDK4 (pyruvate dehydrogenase kinase 4) gene expression were up-regulated through the direct binding of FKHR to the promoter region of the gene in C2C12 cells. These results suggest that FKHR has an important role in the regulation of energy metabolism, at least in part, through the up-regulation of PDK4 gene expression in skeletal muscle during starvation.
    Biochemical Journal 11/2003; 375(Pt 2):365-71. DOI:10.1042/BJ20030022 · 4.40 Impact Factor
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    ABSTRACT: Semaphorins provide crucial attractive and repulsive cues involved in axon guidance during neural development. Out of them, Semaphorin 4D (Sema4D) is enriched in the nervous and immune tissues, and acts as proliferative and survival factors of peripheral lymphocytes in the immune system, but is poorly understood in the nervous system. By using PC12 cells which are well known to differentiate into neural cells in response to nerve growth factor (NGF), we found that soluble forms of Sema4D had neurotrophic effects which were inhibited by neutralizing antibodies to Sema4D. Sema4D strikingly potentiated neurite outgrowth in the presence of 50 ng/ml NGF and increased sensitivity to NGF. Cells responded to very low concentrations of NGF in the presence of 1 nM Sema4D. Activation of following signal proteins, protein kinase C (PKC), L-type of voltage-dependent Ca(2+) channel, and phosphatidylinositol (PI) 3-kinase mediated neurotrophic neurite-outgrowth action of Sema4D. These findings suggest a new function of Sema4D as a neurotrophic signal in PC12 cells.
    Biochemical and Biophysical Research Communications 03/2003; 301(2):304-10. DOI:10.1016/S0006-291X(02)03023-1 · 2.30 Impact Factor
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    ABSTRACT: In C. elegans, insulin-like hormone signal pathway plays a significant role in longevity. In particular, daf-16 gene product is indispensable factor for this lifespan-extension. This signal pathway is critical for dauer formation, which is a similar state to hibernation in mammals. We examined the expression level of mammalian daf-16 homologues, Foxo 1,3, and 4 (FKHR, FKHRL1, and AFX) mRNAs in the rat skeletal muscles during aging and in 30% caloric restricted of ad libitum fed. The expression level of AFX mRNA was significantly higher at 6 and 12 months than at 3 and 26 months, and FKHRL1 expression was significantly higher at 6 months than at 3 and 26 months but FKHR expression showed no significant change with age. We observed a characteristic expression of AFX and FKHR mRNAs to be significantly higher in the second day in caloric restriction by every-other-day feeding than in ad libitum fed. This suggests that caloric restriction may increase the expression of FKHR-family genes and prevent the aging process in the skeletal muscles.
    Microscopy Research and Technique 11/2002; 59(4):331-4. DOI:10.1002/jemt.10213 · 1.15 Impact Factor
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    ABSTRACT: The Rho family GTPase has been implicated in plexin-B1, a receptor for Semaphorin 4D (Sema4D), mediating signal transduction. Rho may also play a function in this signaling pathway as well as Rac, but the mechanisms for Rho regulation are poorly understood. In this study, we have identified two kinds of PDZ domain-containing Rho-specific guanine nucleotide exchange factors (RhoGEFs) as proteins interacting with plexin-B1 cytoplasmic domain. These PDZ domain-containing RhoGEFs showed significant homology to human KIAA0380 (PDZ-RhoGEF) and LARG (KIAA0382), respectively. Both KIAA0380 and LARG could bind plexin-B1 and a deletion mutant analysis of plexin-B1, KIAA0380 and LARG revealed that KIAA0380 and LARG bound plexin-B1 cytoplasmic tail through their PDZ domains. The tissue distribution analysis indicated that plexin-B1 was co-localized with KIAA0380 and LARG in various tissues. Immunocytochemical analysis showed that LARG was recruited to plasma membrane by plexin-B1. These results suggest that PDZ domain-containing RhoGEFs play a role in Sema4D-plexin-B1 mediating signal transduction.
    Biochemical and Biophysical Research Communications 10/2002; 297(1):32-7. DOI:10.1016/S0006-291X(02)02122-8 · 2.30 Impact Factor
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    ABSTRACT: We investigated the effects of aging and denervation on the gene expression of uncoupling proteins (UCPs) in slow-twitch soleus and fast-twitch gastrocnemius muscles. In a comparison between the control limbs of 6- and 24-month-old rats, the mRNA levels of UCP3, heart-type fatty acid binding protein (HFABP), and glucose transporter-4 (GLUT4) were considerably lower in the gastrocnemius muscles of the older rats, whereas no significant differences in the mRNA levels of those genes as well as UCP2 and cytochrome oxidase subunit IV (COX-IV) were observed in the soleus muscles of young and old rats. The UCP3 and COX-IV protein levels were also reduced considerably in the aged gastrocnemius muscles with atrophy. Denervation of the sciatic nerve caused an increase in UCP3 mRNA levels in both muscles, but the regulation of other genes contrasted between the two types of skeletal muscles. In spite of the increased mRNA level, a remarkable reduction in UCP3 protein was found in the denervated gastrocnemius muscles. These results indicate that the effects of aging and denervation on the gene expression of UCPs, HFABP, GLUT4, and COX-IV are different between the muscle types. The reduction in the mitochondrial UCP3 and COX proteins in aged fast-twitch muscles may have a negative effect on energy metabolism and thermogenesis in old animals.
    Journal of Biochemistry 09/2002; 132(2):309-15. DOI:10.1093/oxfordjournals.jbchem.a003225 · 2.58 Impact Factor
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    ABSTRACT: Semaphorins are known to act as chemorepulsive molecules that guide axons during neural development. Sema4C, a group 4 semaphorin, is a transmembrane semaphorin of unknown function. The cytoplasmic domain of Sema4C contains a proline-rich region that may interact with some signaling proteins. In this study, we demonstrate that Sema4C is enriched in the adult mouse brain and associated with PSD-95 isoforms containing PDZ (PSD-95/DLG/ZO-1) domains, such as PSD-95/SAP90, PSD-93/chapsin110, and SAP97/DLG-1, which are concentrated in the post-synaptic density of the brain. In the neocortex, S4C is enriched in the synaptic vesicle fraction and Triton X-100 insoluble post-synaptic density fraction. Immunostaining for Sema4C overlaps that for PSD-95 in superficial layers I-IV of the neocortex. In neocortical culture, S4C is colocalized with PSD-95 in neurons, with a dot-like pattern along the neurites. Sema4C thus may function in the cortical neurons as a bi-directional transmembrane ligand through interacting with PSD-95.
    Journal of Biological Chemistry 04/2001; 276(12):9174-81. DOI:10.1074/jbc.M009051200 · 4.57 Impact Factor
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    ABSTRACT: In situ hybridization and RT-PCR analyses have revealed that, among three Kv4.3 splice variants (a, b, and c) with distinct C-terminal cytoplasmic domains, the mRNA for Kv4.3a is abundant in cerebral cortex, cerebellum, olfactory bulb, and medulla oblongata, whereas the mRNA for Kv4.3c is localized mainly to hippocampus. Three new distinct splice variants of Kv4.3 (Kv4.3d, e and f), which consist of 601, 635, and 628 amino acids, respectively, and have distinct C-terminal cytoplasmic domains, were isolated from rat brain by RT-PCR. Kv4.3b, d, e and f were expressed at much lower levels in brain. Mutagenesis which removed 149 amino acids in C-terminal domain of Kv4.3a significantly slowed its rate of recovery from inactivation as measured in heterologous expression in HEK293 cells. Surprisingly, however, neither the rate of inactivation nor voltage dependence of the activation and inactivation were changed.
    Life Sciences 04/2001; 68(15):1703-1716. DOI:10.1016/S0024-3205(01)00958-4 · 2.70 Impact Factor

Publication Stats

2k Citations
138.78 Total Impact Points


  • 1993–2012
    • Osaka City University
      • Graduate School of Medicine
      Ōsaka, Ōsaka, Japan
  • 2007–2008
    • Sonoda Women's University
  • 2004
    • Kumamoto University
      • Department of Molecular Genetics
      Kumamoto, Kumamoto, Japan
  • 2000–2001
    • The Graduate University for Advanced Studies
      Миура, Kanagawa, Japan
    • Japan Science and Technology Agency (JST)
      Edo, Tōkyō, Japan
  • 1995–2001
    • Osaka University
      • Division of Neuroscience
      Suika, Ōsaka, Japan