著者 Takeuchi, Tomoya| Harada, Yuika| Moriyama, Satomi| Furuta, Kazuyuki| Tanaka, Satoshi| Miyaji Takaaki| Omote, Hiroshi| Moriyama, Yoshinori| Hiasa, Miki|
抄録 Mast cells are secretory cells that play an important role in host defense by discharging various intragranular contents, such as histamine and serotonin, upon stimulation of Fc receptors. The granules also contain spermine and spermidine, which can act as modulators of mast cell function, although the mechanism underlying vesicular storage remains unknown. Vesicular polyamine transporter (VPAT), the fourth member of the SLC18 transporter family, is an active transporter responsible for vesicular storage of spermine and spermidine in neurons. In the present study, we investigated whether VPAT functions in mast cells. RT-PCR and Western blotting indicated VPAT expression in murine bone marrow-derived mast cells (BMMCs). Immunohistochemical analysis indicated that VPAT is colocalized with VAMP3 but not with histamine, serotonin, cathepsin D, VAMP2, or VAMP7. Membrane vesicles from BMMCs accumulated spermidine upon the addition of ATP in a reserpine- and bafilomycin A1-sensitive manner. BMMCs secreted spermine and spermidine upon the addition of either antigen or A23187 in the presence of Ca2+, and the antigen-mediated release, which was shown to be temperature-dependent and sensitive to bafilomycin A1 and tetanus toxin, was significantly suppressed by VPAT gene RNA interference. Under these conditions, expression of vesicular monoamine transporter 2 was unaffected, but antigen-dependent histamine release was significantly suppressed, which was recovered by the addition of 1 mm spermine. These results strongly suggest that VPAT is expressed and is responsible for vesicular storage of spermine and spermidine in novel secretory granules that differ from histamine- and serotonin-containing granules and is involved in vesicular release of these polyamines from mast cells.
キーワード histamine mast cell polyamine secretory granules spermine transporter vesicles vesicular polyamine transporter
備考 2018年3月公開予定
発行日 2017-03
出版物タイトル Journal of Biological Chemistry
292巻
9号
出版者 American Society for Biochemistry and Molecular Biology
開始ページ 3909
終了ページ 3918
ISSN 0021-9258
NCID AA00251083
資料タイプ 学術雑誌論文
言語 English
OAI-PMH Set 岡山大学
著作権者 https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja
論文のバージョン publisher
PubMed ID 28082679
DOI 10.1074/jbc.M116.756197
Web of Sience KeyUT 000395542500031
関連URL https://doi.org/10.1074/jbc.M116.756197
著者 Motomura, Taiki| Suga, Michihiro| Hienerwadel, Rainer| Nakagawa, Akiko| Lai, Thanh-Lan| Nitschke, Wolfgang| Kuma, Takahiro| Sugiura, Miwa| Boussac, Alain| Shen, Jian-Ren|
抄録 Photosystem II catalyzes light-induced water oxidation leading to the generation of dioxygen indispensable for sustaining aerobic life on Earth. The Photosystem II reaction center is composed of D1 and D2 proteins encoded by psbA and psbD genes, respectively. In cyanobacteria, different psbA genes are present in the genome. The thermophilic cyanobacterium Thermosynechococcus elongatus contains three psbA genes: psbA1, psbA2, and psbA3, and a new c-type heme protein, Tll0287, was found to be expressed in a strain expressing the psbA2 gene only, but the structure and function of Tll0287 are unknown. Here we solved the crystal structure of Tll0287 at a 2.0 Å resolution. The overall structure of Tll0287 was found to be similar to some kinases and sensor proteins with a Per-Arnt-Sim-like domain rather than to other c-type cytochromes. The fifth and sixth axial ligands for the heme were Cys and His, instead of the His/Met or His/His ligand pairs observed for most of the c-type hemes. The redox potential, E½, of Tll0287 was -255 ± 20 mV versus normal hydrogen electrode at pH values above 7.5. Below this pH value, the E½ increased by ≈57 mV/pH unit at 15 °C, suggesting the involvement of a protonatable group with a pKred = 7.2 ± 0.3. Possible functions of Tll0287 as a redox sensor under microaerobic conditions or a cytochrome subunit of an H2S-oxidizing system are discussed in view of the environmental conditions in which psbA2 is expressed, as well as phylogenetic analysis, structural, and sequence homologies.
キーワード D1 protein His-Cys heme axial coordination PAS domain PAS-like domain Tll0287 X-ray crystallography cytochrome heme photosynthesis photosystem II
備考 2018年6月公開予定
発行日 2017-06
出版物タイトル Journal of Biological Chemistry
292巻
23号
出版者 American Society for Biochemistry and Molecular Biology
開始ページ 9599
終了ページ 9612
ISSN 0021-9258
NCID AA00251083
資料タイプ 学術雑誌論文
言語 English
OAI-PMH Set 岡山大学
著作権者 https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja
論文のバージョン publisher
PubMed ID 28428249
DOI 10.1074/jbc.M116.746263
Web of Sience KeyUT 000403113000012
関連URL https://doi.org/10.1074/jbc.M116.746263