横断的・総合的な幼稚園教育教員養成プログラムの構築研究

本研究では，別冊『－平成30年度広島大学大学院教育学研究科共同研究プロジェクト－横断的・総合的な幼稚園教育教員養成プログラムの構築研究論文集』を作成し，紙幅の都合で本報告書に掲載できなかった調査・研究の成果を掲載した

Different Photoperiodic Responses in Four Lines of Japanese Quail

Organisms measure day length to better adapt to seasonal changes in the environment; this phenomenon is called photoperiodism. The Japanese quail has a highly sophisticated photoperiodic mechanism and is an excellent model for the study of photoperiodism. Various lines of quail have been established during the domestication process. In the present study, we examined the effect of long day (LD) followed by short day (SD) on testicular weight in four lines of quail (L, AMRP, NIES-Br, and WE). When the quail were raised under SD conditions, testicular development was suppressed in all examined lines. The speed of the LD-induced testicular development of NIES-Br line was faster than that of AMRP line, while the speed of the SD-induced testicular regression of L line was significantly faster than that of WE line. These quail lines provide excellent model to uncover the underlying mechanism of seasonal testicular regression

An In-Cell Fluorogenic Tag–Probe System for Protein Dynamics Imaging Enabled by Cell-Penetrating Peptides

Fluorogenic probes are useful as molecular tools in chemical biology because they can overcome noise associated with background emission. Previously, using a leucine zipper assembly, we developed a fluorogenically active ZIP tag–probe pair. A probe peptide was designed as an α-helical peptide containing 4-nitrobenzo-2-oxa-1,3-diazole, a solvatochromic fluorescent dye. Tag peptides were designed as antiparallel 2 α-helical peptides, and the tag and probe together form the 3 α-helical bundle structure of the leucine zipper. The use of the system was limited to membrane proteins or targets on the cellular surface because the probe peptide was not compatible with cell penetration. In this study, a challenge for the fluorescent imaging of proteins inside the cells was conducted by development of the ZIP tag–probe system as the second generation. To enable the cell penetration of the probe peptide, the addition of a cell penetrating peptide sequence was tested and a probe peptide with a C-terminal octa-arginine was shown to have high affinity for the tag peptide. In addition to attachment of a CPP structure, pretreatment of cells by 1-pyrenebutyrate enhanced distribution of the probe peptide into the cytosol. Observed colocalization of fluorescence of monomer Kusabira Orange and 4-nitrobenzo-2-oxa-1,3-diazole indicates our fluorogenic tag–probe system can be utilized with tagged proteins. Following stimulation by phorbol ester, the translocation of protein kinase C was tracked by the fluorescence of 4-nitrobenzo-2-oxa-1,3-diazole, suggesting the formation of the noncovalently assembled tag–probe pairing is maintained during the translocation, even when the concentration of the probe peptide is reduced to 0.1 μM. The results indicated that the dynamic change of the protein localization by chemical stimulations can be revealed by the ZIP tag–probe system. Above all, the system is simple to handle and highly compatible with virtually any protein inside the cells

Rose Bengal Promoted Catalytic Amyloid-β Oxygenation via Sono-Activation

Catalytic photo-oxygenation of amyloid-β is a leading therapeutic strategy for the treatment of Alzheimer disease. However, the limited tissue-permeability of light hampers its clinical application. We here report an alternative catalytic sono-oxygenation strategy to circumvent this problem. Amyloid-β aggregates were oxygenated using rose bengal as a sonosensitizer under ultrasound irradiation. Structure-activity relationships revealed that xanthene-derived catalysts containing halogen atoms furnished superior amyloid oxygenation activity

DNA Methylation Is a Critical Cell-Intrinsic Determinant of Astrocyte Differentiation in the Fetal Brain

AbstractAstrocyte differentiation, which occurs late in brain development, is largely dependent on the activation of a transcription factor, STAT3. We show that astrocytes, as judged by glial fibrillary acidic protein (GFAP) expression, never emerge from neuroepithelial cells on embryonic day (E) 11.5 even when STAT3 is activated, in contrast to E14.5 neuroepithelial cells. A CpG dinucleotide within a STAT3 binding element in the GFAP promoter is highly methylated in E11.5 neuroepithelial cells, but is demethylated in cells responsive to the STAT3 activation signal to express GFAP. This CpG methylation leads to inaccessibility of STAT3 to the binding element. We suggest that methylation of a cell type-specific gene promoter is a pivotal event in regulating lineage specification in the developing brain