Bcl-xL induces Drp1-dependent synapse formation in cultured hippocampal neurons

Maturation of neuronal synapses is thought to involve mitochondria. Bcl-xL protein inhibits mitochondria-mediated apoptosis but may have other functions in healthy adult neurons in which Bcl-xL is abundant. Here, we report that overexpression of Bcl-xL postsynaptically increases frequency and amplitude of spontaneous miniature synaptic currents in rat hippocampal neurons in culture. Bcl-xL, overexpressed either pre or postsynaptically, increases synapse number, the number and size of synaptic vesicle clusters, and mitochondrial localization to vesicle clusters and synapses, likely accounting for the changes in miniature synaptic currents. Conversely, knockdown of Bcl-xL or inhibiting it with ABT-737 decreases these morphological parameters. The mitochondrial fission protein, dynamin-related protein 1 (Drp1), is a GTPase known to localize to synapses and affect synaptic function and structure. The effects of Bcl-xL appear mediated through Drp1 because overexpression of Drp1 increases synaptic markers, and overexpression of the dominant-negative dnDrp1-K38A decreases them. Furthermore, Bcl-xL coimmunoprecipitates with Drp1 in tissue lysates, and in a recombinant system, Bcl-xL protein stimulates GTPase activity of Drp1. These findings suggest that Bcl-xL positively regulates Drp1 to alter mitochondrial function in a manner that stimulates synapse formation

Research and development on membrane IS process for hydrogen production using solar heat

ISプロセスでは、ヨウ素（I）と硫黄（S）の化合物を循環物質として用いて、以下3つの反応で水を熱分解して水素を製造する：(i)ブンゼン反応 SO2+I2+2H2O → H2SO4+2HI; (ii)ヨウ化水素分解反応 2HI → H2+I2; (iii)硫酸分解反応 H2SO4 → H2O+SO2+0.5O2。本論文では、我々がこれまでに行ってきた(i)～(iii)に関する研究開発の概要を説明した。(i)については、放射線グラフト電解質膜を装着した電気透析装置を作製し、室温かつ低電力で反応を行う技術を開発した。(ii)については、水素透過性シリカ膜を装着した膜型反応器を作製し、約400℃で高効率に反応を行う技術を開発した。(iii)については、酸素透過性シリカ膜に白金/酸化チタン複合触媒を担持させることで膜型反応器を作製し、約600℃で高効率に反応を行う技術を開発した。このように、ISプロセスの産業実用化に向け、(i)～(iii)の各要素技術の開発は順調に進んでいる

ロジョウ セイカツシャ シエン ノ シュウキョウセイ カチ キョウドウセイ ボランティア ハ ナゼ オテラ デ オニギリ ヲ ニギルノカ

論

Essential role of Epac2/Rap1 signaling in regulation of insulin granule dynamics by cAMP

cAMP is well known to regulate exocytosis in various secretory cells, but the precise mechanism of its action remains unknown. Here, we examine the role of cAMP signaling in the exocytotic process of insulin granules in pancreatic beta cells. Although activation of cAMP signaling alone does not cause fusion of the granules to the plasma membrane, it clearly potentiates both the first phase (a prompt, marked, and transient increase) and the second phase (a moderate and sustained increase) of glucose-induced fusion events. Interestingly, all granules responsible for this potentiation are newly recruited and immediately fused to the plasma membrane without docking (restless newcomer). Importantly, cAMP-potentiated fusion events in the first phase of glucose-induced exocytosis are markedly reduced in mice lacking the cAMP-binding protein Epac2 (Epac2ko/ko). In addition, the small GTPase Rap1, which is activated by cAMP specifically through Epac2 in pancreatic beta cells, mediates cAMP-induced insulin secretion in a protein kinase A-independent manner. We also have developed a simulation model of insulin granule movement in which potentiation of the first phase is associated with an increase in the insulin granule density near the plasma membrane. Taken together, these data indicate that Epac2/Rap1 signaling is essential in regulation of insulin granule dynamics by cAMP, most likely by controlling granule density near the plasma membrane