OGG1は活性酸素種からマウス精子幹細胞を守る

京都大学新制・課程博士博士(医学)甲第23086号医博第4713号新制||医||1050(附属図書館)京都大学大学院医学研究科医学専攻(主査)教授 斎藤 通紀, 教授 藤田 恭之, 教授 近藤 玄学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA

Fabrication of single-crystalline plasmonic nanostructures on transparent and flexible amorphous substrates

A new experimental technique is developed for producing a high-performance single-crystalline Ag nanostructure on transparent and flexible amorphous substrates for use in plasmonic sensors and circuit components. This technique is based on the epitaxial growth of Ag on a (001)-oriented single-crystalline NaCl substrate, which is subsequently dissolved in ultrapure water to allow the Ag film to be transferred onto a wide range of different substrates. Focused ion beam milling is then used to create an Ag nanoarray structure consisting of 200 cuboid nanoparticles with a side length of 160 nm and sharp, precise edges. This array exhibits a strong signal and a sharp peak in plasmonic properties and Raman intensity when compared with a polycrystalline Ag nanoarray

Identification of the nuclear export signal in the helix–loop–helix inhibitor Id1

AbstractId proteins play important roles in cellular differentiation and proliferation by negatively regulating basic helix–loop–helix transcription factors. Although their intracellular localization may change depending on the biological situation, little is known about the molecular determinants underlying such changes. Here we report the identification of a nuclear export signal (NES) in Id1. The identified NES was different from that of Id2, but had the ability to confine heterologous green fluorescent protein to the cytoplasm. Thus, our results indicate that the intracellular localization of Id1 is regulated differently from that of Id2

S100A1・S100Bの骨格系組織の発生及び関節軟骨の維持に対する機能の解析

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 高戸 毅, 東京大学准教授 小川 純人, 東京大学講師 藤尾 圭志, 東京大学講師 廣瀬 旬, 東京大学講師 篠田 裕介University of Tokyo(東京大学

Cdc42 is required for male germline niche development in mice

精子形成促進分子GDNFの制御機構の解明 --男性不妊治療への応用に期待--. 京都大学プレスリリース. 2021-08-19.Spermatogonial stem cells (SSCs) are maintained in a special microenvironment called a niche. However, much is unknown about components that constitute the niche. Here, we report that Cdc42 is essential for germline niche development. Sertoli cell-specific Cdc42-deficient mice showed normal premeiotic spermatogenesis. However, germ cells gradually disappeared during haploid cell formation and few germ cells remained in the mature testes. Spermatogonial transplantation experiments revealed a significant loss of SSCs in Cdc42-deficient testes. Moreover, Cdc42 deficiency in Sertoli cells downregulated GDNF, a critical factor for SSC maintenance. Cdc42-deficient Sertoli cells also exhibited lower nuclear MAPK1/3 staining. Inhibition of MAP2K1 or depletion of Pea15a scaffold protein downregulated GDNF expression. A screen of transcription factors revealed that Cdc42-deficient Sertoli cells downregulate DMRT1 and SOX9, both of which are critical for Sertoli cell development. These results indicate that Cdc42 is essential for niche function via MAPK1/3-dependent GDNF secretion

Optimal Temperature of Graft Preservation after ex Vivo Gene Transfer in Lung Isografts

The aim of this study was to determine the optimal temperature of graft preservation after ex vivo gene transfer to rat lung isografts. Left lungs were harvested and infused with cationic lipid/LacZ-DNA complex via the pulmonary artery, and the grafts were stored for 4h. The grafts (n＝7) were allocated into groups IﾝIV according to the storage temperature:4℃, 10℃, 16℃, and 23℃, respectively. Forty-eight h after orthotopic transplantation, the arterial blood gas was analyzed and the peak airway pressure (PAP) and the level of LacZ protein production in the grafts were measured by reverse transcription polymerase chain reaction. After reperfusion, the grafts were stained with hematoxylin and eosin. The grafts in groups III and IV showed more deterioration as evidenced by decreased arterial oxygen tension, increased PAP, and predominant infiltration of inflammatory cells compared with groups I and II. The level of LacZ production was significantly lower in group I than in groups IIﾝIV. The optimal temperature of lung graft preservation after ex vivo gene transfer was determined to be 10℃, balancing considerations of lung injury and efficiency of transgene expression.</p

Low dose RAI ablation

Outpatient ablation therapy with low-dose radioactive iodine (RAI) is applied to non-low-risk papillary thyroid cancer patients due to a chronic shortage of inpatient RAI treatment wards in Japan. We used the maximum dosage available for outpatient therapy of 30 mCi of RAI for ablation and diagnostic (Dx) whole-body scintigraphy (WBS). This study aimed to examine the significance of the second dose of 30 mCi. DxWBS was performed 6 months after ablation, and assessment of success or failure was performed 12 months after ablation. A second WBS was performed in the remaining RAI accumulation cases in the neck on DxWBS. The criteria for successful ablation was negative cervical accumulation on WBS, thyroid stimulating hormone-suppressed thyroglobulin (sup-Tg) below 1.0 ng / mL, and no increase in thyroglobulin antibody (TgAb) level. At the time of DxWBS, 35 / 68 cases met the successful criteria, and 45 cases achieved success at assessment. Sup-Tg values decreased significantly after ablation and decreased further after DxWBS in successful ablation cases, whereas those were not changed in ablation failure cases. Findings indicated that RAI used in DxWBS had therapeutic effects. It makes sense to use 30 mCi for DxWBS, given the current difficulty of inpatient ablation therapy with high-dose RAI

Regulation of Id2 expression by CCAAT/enhancer binding protein β

Mice deficient for Id2, a negative regulator of basic helix–loop–helix (bHLH) transcription factors, exhibit a defect in lactation due to impaired lobuloalveolar development during pregnancy, similar to the mice lacking the CCAAT enhancer binding protein (C/EBP) β. Here, we show that Id2 is a direct target of C/EBPβ. Translocation of C/EBPβ into the nucleus, which was achieved by using a system utilizing the fusion protein between C/EBPβ and the ligand-binding domain of the human estrogen receptor (C/EBPβ-ERT), demonstrated the rapid induction of endogenous Id2 expression. In reporter assays, transactivation of the Id2 promoter by C/EBPβ was observed and, among three potential C/EBPβ binding sites found in the 2.3 kb Id2 promoter region, the most proximal element was responsible for the transactivation. Electrophoretic mobility shift assay (EMSA) identified this element as a core sequence to which C/EBPβ binds. Chromatin immunoprecipitation (ChIP) furthermore confirmed the presence of C/EBPβ in the Id2 promoter region. Northern blotting showed that Id2 expression in C/EBPβ-deficient mammary glands was reduced at 10 days post coitus (d.p.c.), compared with that in wild-type mammary glands. Thus, our data demonstrate that Id2 is a direct target of C/EBPβ and provide insight into molecular mechanisms underlying mammary gland development during pregnancy