Mutations in Ran system affected telomere silencing in Saccharomyces cerevisiae

The Ran GTPase system regulates the direction and timing of several cellular events, such as nuclear-cytosolic transport, centrosome formation, and nuclear envelope assembly in telophase. To gain insight into the Ran system\u27s involvement in chromatin formation, we investigated gene silencing at the telomere in several mutants of the budding yeast Saccharomyces cerevisiae, which had defects in genes involved in the Ran system. A mutation of the RanGAP gene, rna1-1, caused reduced silencing at the telomere, and partial disruption of the nuclear Ran binding factor, yrb2-Δ2, increased this silencing. The reduced telomere silencing in rna1-1 cells was suppressed by a high dosage of the SIR3 gene or the SIT4 gene. Furthermore, hyperphosphorylated Sir3 protein accumulated in the rna1-1 mutant. These results suggest that RanGAP is required for the heterochromatin structure at the telomere in budding yeast. © 2007 Elsevier Inc. All rights reserved

Phosphorylation of the RSRSP stretch is critical for splicing regulation by RNA-Binding Motif Protein 20 (RBM20) through nuclear localization

RBM20 is a major regulator of heart-specific alternative pre-mRNA splicing of TTN encoding a giant sarcomeric protein titin. Mutation in RBM20 is linked to autosomal-dominant familial dilated cardiomyopathy (DCM), yet most of the RBM20 missense mutations in familial and sporadic cases were mapped to an RSRSP stretch in an arginine/serine-rich region of which function remains unknown. In the present study, we identified an R634W missense mutation within the stretch and a G1031X nonsense mutation in cohorts of DCM patients. We demonstrate that the two serine residues in the RSRSP stretch are constitutively phosphorylated and mutations in the stretch disturb nuclear localization of RBM20. Rbm20 S637A knock-in mouse mimicking an S635A mutation reported in a familial case showed a remarkable effect on titin isoform expression like in a patient carrying the mutation. These results revealed the function of the RSRSP stretch as a critical part of a nuclear localization signal and offer the Rbm20 S637A mouse as a good model for in vivo study

Magnetic dichroism in angular-resolved hard X-ray photoelectron spectroscopy from buried layers

This work reports the measurement of magnetic dichroism in angular-resolved photoemission from in-plane magnetized buried thin films. The high bulk sensitivity of hard X-ray photoelectron spectroscopy (HAXPES) in combination with circularly polarized radiation enables the investigation of the magnetic properties of buried layers. HAXPES experiments with an excitation energy of 8 keV were performed on exchange-biased magnetic layers covered by thin oxide films. Two types of structures were investigated with the IrMn exchange-biasing layer either above or below the ferromagnetic layer: one with a CoFe layer on top and another with a Co$_2$FeAl layer buried beneath the IrMn layer. A pronounced magnetic dichroism is found in the Co and Fe $2p$ states of both materials. The localization of the magnetic moments at the Fe site conditioning the peculiar characteristics of the Co$_2$FeAl Heusler compound, predicted to be a half-metallic ferromagnet, is revealed from the magnetic dichroism detected in the Fe $2p$ states

Identification of an Anti–Integrin αvβ6 Autoantibody in Patients With Ulcerative Colitis

指定難病「潰瘍性大腸炎」の自己抗体発見 --新たな診断や治療開発へ--. 京都大学プレスリリース. 2021-03-09.Background and Aims: Ulcerative colitis is the most frequent type of inflammatory bowel disease and is characterized by colonic epithelial cell damage. Although involvement of autoimmunity has been suggested in ulcerative colitis, specific autoantigens/antibodies have yet to be elucidated. Methods: Using 23 recombinant integrin proteins, we performed enzyme-linked immunosorbent assays on sera from patients with ulcerative colitis and controls. Integrin expression and IgG binding in the colon tissues of patients with ulcerative colitis and controls were examined using immunofluorescence and coimmunoprecipitation, respectively. The blocking activity of autoantibodies was examined using solid-phase binding and cell adhesion assays. Results: Screening revealed that patients with ulcerative colitis had IgG antibodies against integrin αvβ6. In the training and validation groups, 103 of 112 (92.0%) patients with ulcerative colitis and only 8 of 155 (5.2%) controls had anti–integrin αvβ6 antibodies (P < .001), resulting in a sensitivity of 92.0% and a specificity of 94.8% for diagnosing ulcerative colitis. Anti–integrin αvβ6 antibody titers coincided with ulcerative colitis disease activity, and IgG1 was the major subclass. Patient IgG bound to the integrin αvβ6 expressed on colonic epithelial cells. Moreover, IgG of patients with ulcerative colitis blocked integrin αvβ6–fibronectin binding through an RGD (Arg-Gly-Asp) tripeptide motif and inhibited cell adhesion. Conclusions: A significant majority of patients with ulcerative colitis had autoantibodies against integrin αvβ6, which may serve as a potential diagnostic biomarker with high sensitivity and specificity

2017～2019年度 関西大学研究拠点形成支援経費研究成果報告書

目次・研究成果の概要・2-1　工藤 宏人・宮前 翼・上田 正人・村山 憲弘・林 順一 "ノーリア骨格をテンプレートとした空孔内に水酸基を有する架橋化合物の合成とそれらの金属イオン包接性能" ネットワークポリマー論文集 vol.41, No.2, 65 - 71 (2020).・2-2　Mitsuaki Matsuoka, Kaho Yokoyama, Kohei Okura, Norihiro Murayama, Masato Ueda, Makio Naito " Synthesis of Geopolymers from Mechanically Activated Coal Fly Ash and Improvement of Their Mechanical Properties" Minerals 9, 791- 801 (2019).・2-3　Daisuke Shimoyama, Ryo Sekiya, Hiroto Kudo, Takeharu Haino, "Feet-to-Feet Connected Trisresorcinarenes" Organic Letters 22, 352 - 356 (2019).・2-4　Masato Ueda, Masahiko Ikeda, Shigeo Mori, Kenji Doi, Hisashi Kitagaki, Shuntaro Terauchi "Mechanical Properties of Additively Manufactured Porous Titanium with Sub-Millimetre Structural Units" Materials Transactions Vol.60, No.9, 1792 - 1798 (2019).・2-5　五十井 浩平・白杉 文香・松岡 光昭・林 順一・村山 憲弘 "種々のMg-Fe系複合酸化物を用いた希薄水溶液中のホウ素およびヒ素の除去" 環境資源工学 66, 29 - 35 (2019).・2-6　Toru Maruyama, Mitsuyoshi Tamaki, Keisuke Nakamura, Gou Nakamura "EFFECT OF MOLTEN METAL TEMPERATURE ON MOLD FILLING IN EVAPORATIVE PATTERN CASTING" International Journal of Metalcasting 13, 611–617 (2019).・2-7　Ryuta Saito, Toru Maruyama, Toshiki Nakamura, Hitoshi Yanagitani, Takahiro Sakai, Kouji Nakamoto "Influence of Tellurium Addition to Spheroidal Graphite Cast Iron on the Number of Graphite Particles" International Journal of Metalcasting Vol.13, 3, 571-577 (2018).・2-8　Masato Ueda, Rika Yamaguchi, Chika Fujita, Masahiko Ikeda "Control of Cell Adhesion on Titanium Dioxide by Light Irradiation" Materials Science Forum Vol.941, 2507 - 2512 (2018).・2-9　Hiroto Kudo, Mari Fukunaga, Kohei Shiotsuki, Hiroya Takeda, Hiroki Yamamoto, Takahiro Kozawa, Takeo Watanabe "Synthesis of hyperbranched polyacetals containing C-(4-t-butylbenz)calix[4]resorcinarene: Resist properties for extreme ultraviolet (EUV) lithography" Reactive and Functional Polymers 131, 361 - 367 (2018).・2-10　大隈 修・前 一廣・林 順一 "直接液化による豪州ビクトリア褐炭の高度利用 : 改新BCLプロセスによる化学原料の生産" Journal of the Japan Institute of Energy 98, 17 - 26 (2019).・2-11　Issei Suzuki, Ayako Kakinuma, Masato Ueda, Takahisa Omata "Flux growth of β-NaGaO₂ single crystals" Journal of Crystal Growth 504, 26 -30 (2018).・2-12　上田 正人、坂本 貴則、池田 勝彦 "電気抵抗率の精密測定による純チタンの組織評価" 環境資源工学 65, 74 -76 (2018).・2-13　Satoshi Imasaka, Hiroyasu Ishii, Jun\u27ichi Hayashi, Sadao Araki, Hideki Yamamoto "Synthesis of CHA-type titanosilicate zeolites using titanium oxide as Ti source and evaluation of their physicochemical properties" Microporous and Mesoporous Materials 273, 243-248 (2019).・2-14　Hiroto Kudo, Shizuya Ohori, Hiroya Takeda, Hiroki Ogawa, Takeo Watanbe, Hiroki Yamamoto, Takahiro Kozawa "Synthesis and Property of Tannic Acid Derivatives and Their Application for Extreme Ultraviolet Laser Lithography System" Journal of Photopolymer Science and Technology Vol.31, 221 - 225 (2018).・2-15　Hiroto Kudo, Tsubasa Miyamae, Kouta Kitagawa, Kohei Isoi, Norihiro Murayama, Jun\u27ichi Hayashi " Synthesis and Metal-Complexation Ability of Cross-Linking Materials Containing Noria-Templated Cavities with Pendant Carboxylic Acid Groups" Chemistry Select 3, 2223 - 2228 (2018).・2-16　上田 正人、池田 勝彦、土井 研児、 森 重雄、北垣 壽、寺内 俊太郎、関 あずさ "骨部分置換用ポーラスチタン : ポリグリコール酸 : 炭酸カルシウム複合体の開発" 高分子論文集 Vol.75, No.1, 69 - 74 (2018).・2-17　Alexandru C Sonoc, Jacob Jeswiet, Norihiro Murayama, Junji Shibata "A study of the application of Donnan dialysis to the recycling of lithium ion batteries" Hydrometallurgy 175, 133 - 143 (2018).2-3は、著作権の関係により非公開としております。2-8は、著作権の関係により非公開としております。2-9は、著作権の関係により非公開としております。2-10は、著作権の関係により非公開としております。2-11は、著作権の関係により非公開としております。2-16は、著作権の関係により非公開としております