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A Study on the Interaction with Takeo Arishima as Seen in Yoshimaro Tanaka’s Diary, *Biou-Shuki*
No full textWork Record of the Archives : Logbook of the Archives : Usage Pattern of the Archives : Organization of the Archives : Annual Report Editing
No full textPhotoinhibition of photosystem I and its photoprotective mechanisms in plants
No full text植物は常に変動する環境にさらされる．例えば，植物が光合成能力を超える光にさらされた場合，吸収された光エネルギーは過剰となり，活性酸素種の生成を引き起こす．活性酸素種は光合成装置に損傷を与え，結果として植物の光合成能力の低下となる（光阻害）．植物はこのような光阻害を回避するために様々な戦略を持つ．光阻害の主要な場所は光化学系IIであることから，植物の光防御機構に関する研究もPSIIが中心であった．しかし近年になって，変動する光環境ではPSIIよりもPSIが顕著な光阻害を受けることが明らかにされ，PSIの光防御機構にも注目が集まっている．ここでは，PSIの光阻害とその防御機構について紹介する．Plants are exposed to constantly changing environments. When light exceeds the photosynthetic capacity of plants, the excess light energy absorbed causes the production of reactive oxygen species (ROS). ROS damages the photosynthetic apparatus, resulting in a decreased photosynthetic activity in plants (photoinhibition). Therefore, plants have various strategies to avoid photoinhibition in response to fluctuations in light intensity. Until recently, photosystem II was thought to be the primary site of photoinhibition, and studies on plant photoprotection mechanisms have focused on PSII. However, since it has been shown that PSI is more significantly photoinhibited than PSII under fluctuating light conditions, the photoprotection mechanism of PSI has also attracted attention. Here, we discuss the photoinhibition of PSI and its photoprotective mechanisms as revealed by recent studies
Structural analysis reveals how tetrameric tyrosine-phosphorylated STAT1 is targeted by the rabies virus P-protein
No full textSignal transducer and activator of transcription (STAT) family members mediate signaling in the Janus kinase (JAK)-STAT pathway and are activated by phosphorylation at a conserved tyrosine residue, resulting in dimerization through reciprocal interactions between the phosphotyrosine and a Src homology 2 (SH2) domain. Tyrosine-phosphorylated STAT (pY-STAT) then translocates to the nucleus to induce the expression of genes encoding antiviral proteins. Although the active and functional forms of STATs are conventionally considered to be dimers, STATs can undergo higher-order oligomerization, which is implicated in regulating transcriptional activity. We present the cryo-electron microscopy (cryo-EM) structure of the tetrameric form of intact pY-STAT1 in complex with DNA, which indicates that interactions between the amino-terminal domains (NTDs) of STAT1 induce oligomerization. The tetrameric structure revealed a compact conformation with a previously uncharacterized binding interface: Two DNA-bound dimers are twofold symmetrically aligned to transform into a tandem DNA-binding model without NTD dimer separation. Moreover, biochemical analyses indicated that the rabies virus P-protein selectively targeted tetrameric pY-STAT1. Combined with data showing which regions contribute to the interaction between pY-STAT1 and the P-protein, we constructed a binding model explaining how P recognizes the pY-STAT1 tetramer. These data provide insight into how pathogenic viruses target signaling pathways that mediate the host immune response
都市祭礼と宗教的なモノの消費 : 東京都・鷲神社と花園神社の酉の市の事例 [全文の要約]
No full textこの博士論文全文の閲覧方法については、以下のサイトをご参照ください。https://www.lib.hokudai.ac.jp/dissertations/copy-guides
