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196 Abstracts / Neuroscience

3-c0� 2 Characterization of SCS as a potent activator for theK1-mediated phosphorylation of tau protein and its associatedroteins from rat brainanzo Suzuki, Fumitaka Kawakami, Hisashi Sasaki, Kenzo Ohtsuki

Laboratory of Genetical Biochemistry and Signal Biology, Graduatechool of Medical Sciences, Kitasato University, Japan

urpose: Recently, we reported that casein kinase 1 (CK1) phophorylateswo functional basic proteins [myelin basic protein (MBP) and tau proteinTP)] in the presence of two sulfated lipids [sulfatide and cholesterol-3-ulfate (CH-3S), SCS] in vitro. The present in vitro study has been carriedut to characterize the SCS-dependent phosphorylation of TP and itsssociated proteins by CK1 in the TP fraction from rat brain.esults and Discussion: It was found that (i), in the presence of SCS, CK1hosphorylated TP and its associated proteins (p82 and p55) in the par-ially purified TP fraction; and (ii) p82 and p55 was identified as eIF-4Bnd syndapin 1, respectively. These results suggest that the accumulatedigh level of SCS preferentially induces the CK1-mediated phosphoryla-ion of TP, eIF-4B and syndapin 1, which are involved in the mechanismsf various neuronal diseases, including Alzheimer’s disease.

3-c0� 4 Activation of the c-fos promoter is modulated by PKAn PC12 cellsakashi Sugiyama, Hirobumi Suzuki

Advanced Core Technology Department, Olympus Corporation,apan

he c-fos protooncogene is thought to contribute to the regulation of nor-al cellular proliferation and differentiation. It has been reported that

pplication of NGF, which leads to cellular differentiation, induced a tran-ient c-fos gene expression in PC12 cells. NGF activates the c-fos promoterhrough two well characterized regulatory elements, the serum responselement (SRE) and the cAMP response element (CRE). Many kinases arenvolved in the transcription through these elements, a contribution ofKA, however, has not been investigated in detail. Using a luminescence

maging system and a human c-fos promoter-driven luciferase expressionector, we analyzed physiological roles of PKA in NGF-induced c-fos pro-oter activation in a single cell level. Inhibitors for PKA enhanced the

ncrease of the c-fos promoter activity without any effects to MEK/MAPKascade. Mutational analysis of the CRE and/or the NFB consensusequence in the regulatory region of the c-fos gene revealed that c-fosromoter activity might be modulated by both CREB and NFB. Finally,e propose a molecular mechanism under the modulation of the c-fosromoter by PKA.

3-c0� 5 Tyrosin kinase is involved in the mGluR1-mediatednward current in the cerebellar molecular layer interneuronsideo Kubota1, Moritoshi Hirono2, Kunihiko Obata2

Supply Unit, Faculty of Medicine, Tokyo Medical and Dentalniversity Hospital, Tokyo, Japan; 2 Neuronal Circuit Mechanismsesearch Group, BSI, RIKEN, Wako, Japan

ctivation of mGluR1 induces an excitatory slow inward current inhe cerebellar molecular layer interneurons (MLIs), such as basket andtellate cells. We addressed the underlying mechanism with whole-cellatch-clamp recordings. Pressure application of the group I mGluR ago-ist DHPG produced a slow inward current in MLIs, which was blockedy an mGluR1 antagonist, CPCCOEt. Bath-applied protein tyrosin kinase

nhibitors, genistein and AG490, considerably reduced the DHPG-inducednward current, although infusion of a PLC inhibitor U73122 into MLIsnly partially inhibited the current amplitude. Furthermore, perfusion of

selective Src kinase inhibitor PP2 significantly suppressed the inward

urrent. These results suggest that mGluR1 activation in MLIs induceshe inward current through a Src-dependent pathway, which is differentrom the mGluR1-TRPC1 signaling cascade in cerebellar Purkinje cells.

esearch funds: KAKENHI (16700344)

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rch 58S (2007) S1–S244

3-c0� 6 Distinct cellular expression of PKC� and PKC� in par-icular interneurons of the mouse telencephalonriko Miura, Yoshiyuki Kubota, Masahiko Watanabe

Department of Anatomy, Hokkaido University Graduate School ofedicine, Sapporo, Japan

rotein kinase C (PKC) is classified as a family of closely related ser-ne/threonine protein kinases that regulate various biological events

ithin the cell. PKC� and PKC�, members of classical PKC, are Ca2+-ependent and activated by diacylglycerol (DAG) in the process of a seriesf phosphorylation events. In this study, we studied cellular expression ofKC� and PKC� in the mouse striatum, cortex, and hippocampus. PKC�nd PKC� were more or less coexpressed in principal neurons, includingedium spiny neurons in the striatum, cortical neurons in the layer II/III,

nd pyramidal cells and granule cells in the hippocampus. However, PKC�as expressed predominantly in cholinergic interneurons and parvalbu-in (PV)-positive interneurons in the striatum, layer V non-pyramidal

eurons and PV-positive interneurons in the cortex, and nNOS-positiventerneurons in the hippocampus. In contrast, pyramidal cells in the layer

selectively expressed PKC�. Therefore, particular interneurons pref-rentially express PKC�, whereas most principal neurons express bothKC� and PKC�.

3-c0� 8 Localization of diacylglycerol kinase � and -� in neuronsasukazu Hozumi, Kaoru Goto

Department of Anatomy and Cell Biology, Yamagata Universitychool of Medicine, Yamagata, Japan

iacylglycerol kinase (DGK) is involved in intracellular signal transduc-ion as a regulator of a second messenger, diacylglycerol. To addresshe functional implications of DGK isozymes in the brain, we haveaised specific antibodies against DGK� and -�. By immunoblot analy-is, we found that immunoreactivities against DGK� and -� were detectedn the light membrane/microsome enriched fraction of rat brains, sug-esting that these isozymes localize to the internal membrane system.mmunohistochemical examination on the cerebellum revealed thatmmunoreactivity for DGK� was detected as punctate or reticular struc-ures in the cytoplasm and dendrites, but not in the axon, of Purkinje cells.he immunoreactivity was also detected diffusely in the cytoplasm oferebellar granule cells. On the other hand, DGK�-immunoreactivity wasbserved as granular structures in the perinuclear region, dendrites andxon of Purkinje cells, but not in cerebellar granule cells. These data sug-est that DGK� and -� play different roles in distinct internal membraneystem in neurons.

esearch funds: KAKENHI (18700337)

3-c0� 9 Lipid components in the detergent-resistant mem-rane microdomain from rat synaptic plasma membranehohei Maekawa1, Daisuke Matsuura1, Katsutoshi Taguchi1,itoshi Yagisawa2

Department of Biology, Kobe-University, Kobe, Japan; 2 Graduatechool of Life Science, University of Hyogo, Hyogo, Japan

embrane microdomains are recovered as a detergent-resistantow-density membrane fraction (DRM) after Triton extraction andentrifugation. Since specific recovery of phosphatidylinositol 4,5-isphosphate (PIP2) in DRM is known in cultured cells, the DRM isonsidered as a signal-processing platform. Little information is howevervailable on the PIP2 content in the DRM prepared from brain, for theI-labeling of live animals are not practical. In this study, we assayed themounts of PIP2 in SPM and SPM-derived DRM using the PH domain ofhospholipase C-delta1 fused to GST. Extracted lipids were separatedn HPTLC and heat-transferred to PVDF membrane. After blocking, anti-ST and ECL system was used to measure the bound GST. About 10%

f PIP2 in SPM was recovered in DRM and no specific localization wasetected. In contrast, nearly half amounts of sphingomyelin and choles-erol, and about 30% of phosphatidylcholine or phosphatidylethanolamineere recovered in DRM.

esearch funds: KAKENHI (16370062)